News Archives



Glomerular Filtration Rate

MDRD Estimated GFR

The National Institutes of Health (NIH) estimates that 20 million people have chronic kidney disease (CKD). CKD is especially prevalent in patients with hypertension, diabetes, cardiovascular disease, in ethnic minorities, in the elderly, and in people who have relatives treated with dialysis. Current recommendations indicate that these patients need to be identified and managed aggressively to decrease progression of CKD. Achieving this goal is a challenge to all health care providers.

Currently, CKD is staged based on estimated glomerular filtration rate (GFR) ranging from Stage 1 to 5. Each stage has unique issues that require attention. To help you detect these patients, the laboratory at CMMC is now reporting estimated GFR (eGFR) with each serum creatinine level ordered. GFR is usually accepted as the best overall index of kidney function in health and disease. A persistently reduced GFR is a specific indication of CKD. Below 60 ml/min/1.73 sq. meter, the prevalence of complications of CKD increases, as does the risk of cardiovascular disease.

The National Kidney Disease Education Program (NKDEP) of the National Institute of Diabetes and Diseases of the Kidney (NIDDK), National Kidney Foundation (NKF) and American Society of Nephrology (ASN) recommend estimating GFR from serum creatinine using the MDRD Study equation. This equation uses serum creatinine in combination with age, sex and race to estimate GFR and therefore improves upon several of the limitations with the use of serum creatinine. The MDRD Study equation has been rigorously developed and validated, is more accurate than measured creatinine clearance from 24-hour urine collections in most patients. NKDEP has provided a very informative website on the subject that will address many of your questions: NIH NKDEP

Twenty-four-hour urine collections may be required to estimate GFR in the following conditions:

  • Extremes of age and body size
  • Severe malnutrition or obesity
  • Disease of skeletal muscle
  • Paraplegia or quadriplegia
  • Vegetarian diet
  • Rapidly changing kidney function
  • Prior to dosing drugs with significant toxicity that are excreted by the kidneys
  • Pregnancy


The following should be noted as related to the eGFR:

  1. The equation that is used is consistent with the NKDEP recommendation. It will be computed automatically by our lab computer based on the measured creatinine and age, race and gender as recorded during the registration. This prints on paper reports and transmits to the electronic medical record systems (Logician and Powerchart).
  2. We do not report the eGFR for patients less than 18 years of age. It will report for all other age groups.
  3. We report the race classification (African-American or non-African American) on the report as a specific detail. This will allow the clinician to know the basis of our computation. Age and gender will appear on the top of the printed reports or at the top of the electronic record in powerchart.
  4. The eGFR will be reported with units of measure of “mL/min” due to space limitations for that field in our computer system. The interpretive information will explain the actual units of “mL/min/1.73 sq. m.”
  5. Results will flag as abnormally low if less than 60 mL/min.
  6. We are currently calibrating our creatinine assays to a conventional standard and plan to move to an IDMS standard sometime in the early part of 2007. The manufacturer of our analytical system has announced the release of a new calibrator this fall. We plan to complete a comprehensive “normal study” as we convert to the IDMS calibrator. We do expect to see a slight shift in results and normal ranges for creatinine when we change calibrators. The eGFR value will remain unchanged.
  7. In general, drug dosing is based on GFR levels that are not adjusted for body surface area. For drug dosing purposes, National Kidney Disease Education Program does not recommend using the MDRD Study equation at this time because the clinical impact on drug dose adjustment has not been compared between current practice and the MDRD Study equation. NKDEP recommends that pharmacists continue to use their current drug dosing methods. As a result, CMMC pharmacists will continue to calculate creatinine clearance via the Cockcroft-Gault equation, the method by which dosing recommendations have been traditionally developed.

Please feel free to contact the pathology staff with any specific questions or concerns related to this topic.


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Fetal Fibronectin

Fetal Fibronectin testing is now available through the laboratory at Rumford Hospital. Fetal fibronectin is useful in assessing the risk of preterm delivery in women who are 22-35 weeks pregnant. There is a greater than 99% chance that delivery will not occur within two weeks of a negative test for Fetal Fibronectin.


Fetal Fibronectin is measured from a vaginal swab specimen collected prior to digital examination or manipulation of the cervix. The specimen can be tested immediately, or a refrigerated specimen can be tested within 3 days of collection.

If you think your practice may use Fetal Fibronectin testing, your staff will require a short course in proper specimen collection. Please contact Michael Eng, M.D. at 795-2338 to arrange training and delivery of specimen collection materials.


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CMMC Laboratory Goes Online

Central Maine Medical Center's Laboratory, assisted by the CMMC Communications Department, has developed an online informational resource for CMMC's laboratory scientists and those who use their services.


The website features a extensive Laboratory Test Info database and provides clinicians with essential information about the many services offered by the CMMC Lab, including a General Information section, specific instructions regarding Specimen/Collection, and a Contact Us directory.


Questions/comments about CMMC Laboratory services should be addressed to CMMC's laboratory director at 795-2330.


Questions/comments about the website's content should be directed to Matt Twomey at 795-2330.


Questions/comments about the function of the website should be directed to Darlene Ryder at 795-2196 or darlene@cmmc.org


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VAP Cholesterol Panel

Now orderable

The VAP Cholesterol Panel is orderable. Mnemonic is: VAP CHOL
This should not be ordered in conjunction with a Coronary Risk Panel.

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Cord Blood Gases

New Orderable for Cord Blood Gases

A new orderable group test for cord blood gases has been added to the order entry system. The group includes: pH, pCO2, pO2 and Base Excess. It is listed as Blood Gas, Cord on Millennium and will soon be incorporated into the newborn Caresets.

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Greiner Tube Conversion Chart

To download the Greiner Tube Conversion Chart click here.

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MSRA Screening Flowchart

for New Admissions

CMMC Laboratory is now performing MRSA Screening by PCR. This technique offers a faster turn around time than the traditional culture method.

To view the MRSA Screening Flowchart click here.

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Microalbumin/Creatinine Ratio

Procedural Change

RANDOM URINE MICROALBUMIN/CREATININE RATIO:
As of Tuesday, June 26, 2007, we will discontinue screening samples for macroalbuminuria with a "dipstick" procedure. As of this date, all urine microalbumin/creatinine ratio determinations will be analyzed directly on the chemistry system without prescreening. If a sample demonstrates an albumin concentration > 18 mg/dL, the following footnote will be appended to the result:

ADDITIONAL FOOTNOTE INFORMATION FOR URINE MICROALBUMIN/CREATININE RATIO:
The absolute albumin concentration on this random urine sample exceeds 18 mg/dL which suggests that macroalbuminuria is present in this sample. Therefore, a microalbumin determination may not be appropriate. A 24-hour urine collection for quantitative protein excretion is suggested if clinically indicated.


Sample Processing Note: Please note that samples submitted from remote sites should be poured off into a leakproof sample transport tube with an appropriate barcoded accession label.

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Antibiogram

Now Available

CMMC Antibiotic Susceptibility Report (Antibiogram) is now available on this website. This data is derived from isolates in the January - December 2006 timeframe for patients registered at CMMC. It does not include data for patients registered at Bridgton or Rumford Hospitals.

Data is presented categorically by patient population and type of sample in both screen and printer friendly formats.

You may navigate to this page by clicking the "Interpretive Information" button on the right side of the home page, or click here.

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Creatinine Change

IDMS Calibration

On Monday, September 24, 2007, all CMHC laboratories will convert to a new calibration for serum creatinine determinations. Reference ranges and serum creatinine results will be slightly lower.

This change is being made to align our creatinine methodology to recommendations made by the National Kidney Disease Education Program (NKDEP). NKDEP is an initiative of the National Institutes of Health, designed to reduce the morbidity and mortality caused by kidney disease and its complications.

The following changes should be noted:

  • After this change is made, serum creatinine values will be approximately 6.5% lower when compared to those measured with the conventional (legacy) calibration.

  • The new reference range for:

    ADULT MALE serum creatinine will be 0.75 – 1.15 mg/dL

    ADULT FEMALE serum creatinine will be 0.55 – 0.95 mg/dL

  • Calculations for eGFR (estimated glomerular filtration rate) using the MDRD equation will be modified to adjust to the IDMS calibration. Consequently, the eGFR values and their interpretation will be unchanged with this conversion.

  • Results will be footnoted for a period of time to alert providers to this change.

To identify the relationship between the “old vs new” creatinine results, a correlation study was performed. The conventional is referred to as the legacy calibration. The new calibration is referred to as the IDMS or (isotope dilution mass spectrometry) calibration. The regression analysis may be viewed by clicking this link.

Please feel free to contact a member of the pathology team if you have any questions on this.


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Autoverification Presentation

CMMC staff present at fall conference.

Matt Twomey, LIS Manager at CMMC, delivered a presentation at the annual fall Northeast Laboratory Conference in Portland, Maine. The presentation described the CMMC lab introduction of autoverification using the Ortho Clinical Diagnostics Fusion 5,1 chemistry system and the Sysmex Alpha hematology system.

To download a copy of the presentation, click this link.

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CMMC Donor Center Presentation

CMMC staff present at fall conference.

Johanna Ward, Transfusion Services Manager at CMMC, delivered a presentation at the annual fall Northeast Laboratory Conference in Portland, Maine. The presentation described "A Collaboration between The American Red Cross and Central Maine Medical Center" to establish a Blood Donation Center.

To download a copy of the presentation, click this link.

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HIV Testing & LD 429

On September 19, 2007, the revised Maine HIV testing statute comes into effect. LD 429 amends some of the requirements for HIV consent and counseling to allow for routine HIV testing. These changes will simplify the testing process and allow providers to more easily comply with the Revised Recommendations for HIV Testing of Adults, Adolescents, and Pregnant Women in Health-Care Settings published by the US Centers for Disease Control in September 2006.

The highlights of the revised Maine statue are:

  • An HIV test must be voluntary and undertaken only with a patient's knowledge and understanding that an HIV test is planned.
  • Consent for HIV testing may now be obtained verbally or in written form by the ordering provider. It is no longer necessary to have patients sign separate HIV Testing consent forms.
  • When obtaining consent, oral or written information must be given to a patient including an explanation of what an HIV infection involves and the meaning of positive and negative test results. A patient must be provided the option to ask questions orally or in writing.
  • Laboratories are no longer required to have the consent in writing to perform a test.
  • Pre-test counseling is no longer a requirement. Pretest counseling should be provided at the discretion of the healthcare provider or as requested by the person who is tested. It is not necessary to document an "opt out" from pretest counseling.
  • Post-test counseling is only required for patients who test positive for HIV. The revised Maine statute has specific requirements for the delivery and content of this information. As a minimum, this must include a discussion of (1) the test results and the reliability and significance of the test results in a confidental setting through personal contact; (2) information on good preventive practices and risk reduction plans; and (3) referrals for medical care and support services.
  • Maine statute identifies specific requirements for source HIV testing of occupational body fluid exposures. Pretest counseling is no longer a requirement however the consent process remains largely unchanged in these situations. CMMC will revise the BFE Source Protocol document accordingly.

Background and Rationale

Changes were made in the Maine HIV testing law in order to facilitate implementation of the federal CDC's recommendations for HIV testing in health-care settings. Changes to Maine HIV testing law addressed two of the major barriers identified by health care providers to routine HIV testing: (1) separate written consent to test for HIV and; (2) pretest counseling.

In September 2006, the federal CDC released Revised Recommendations for HIV Testing of Adults, Adolescents, and Pregnant Women in Health Care Settings. The aim of these recommendations is to make HIV testing a routine part of medical care and expand gains made in diagnosing HIV infection among pregnant women. The recommended health care strategy is routine HIV testing in all health care settings for all adolescents and adults age 13 – 64 years and all pregnant women as well as targeted risk-based testing.

Why test for HIV routinely?

There are significant numbers of HIV infected adolescents and adults in Maine who test very late in the course of their disease and many who are not aware of their infection at all. When "late testers" eventually are linked to health care, they are in poorer health status, have developed resistance to some treatment options, die sooner, and have unknowingly infected others. The proportion of the cohort of untested and late testers has remained fairly consistent despite 20 years of risk-based targeted HIV testing in Maine. HIV testing has to move beyond a risk-based approach in order to more effectively diagnose and treat people with the infection, as well as prevent new infections from occurring. HIV testing is the gateway to both effective treatment and prevention.
  • It is estimated that in Maine there are 300-500 people infected with HIV who don't know it because they haven't been tested. From the Public hearing for LD429 in March, 2007, we learned that some of these HIV infected people had many contacts with the health care system, but were not tested for HIV. The current health care system is missing opportunities to intervene in HIV.
  • About half of people newly diagnosed for HIV receive an AIDS diagnosis within one year of their HIV diagnosis. This means almost half of people diagnosed with HIV are learning about their infection very late, up to 10 years, in the course of their disease.
  • Using national data for estimates, more than half of all HIV-infected adolescents are not tested and remain unaware of their infection.
  • The US CDC estimates that more than half (50-70%) of new HIV infections are caused by people who are infected but untested and unaware of their infection.
  • The majority (up to 68%) of newly HIV diagnosed people change their behaviors to reduce their risk of transmitting HIV to others.
  • Individuals tested and treated earlier in their HIV infection tend to have better health and quality of life outcomes than those testing late in their disease or after the onset of major symptoms.
  • Routine testing in health care settings may help to reduce the stigma associated with HIV testing by normalizing it, thereby reducing the need for exceptional protective requirements associated with HIV testing.

Operational Policy Changes

A number of operational changes will take place over the next 3 - 6 months as policies are developed at our organization. It is important to note that we are in a transition that is subject to many changes as legal and state guidelines are currently being developed (as of August 2007). This information is not intended to provide definitive legal advice but merely provides some interpretive guidance and links to more definitive resources. Users of this information should check this website frequently for additions and/or changes that reflect CMMF's operational changes.

Separate HIV testing consent documents will generally be eliminated. CMMF laboratories will no longer require or accept HIV testing consent forms for routine HIV testing after September 19, 2007. The responsibility for the consent will rest with the ordering provider. Any documentation of consent should be retained by the provider in the patient's record. CMMF outpatient practices, clinics and patient care units should define operational procedures to comply with these statutes and should develop these changes in a manner that is consistent with institutional policy.

We do expect to incorporate some language into the institutional general consent form to inform our patients of the fact that HIV testing is performed routinely according to CDC guidelines. Since consent forms are general in nature and will not apply to every patient on every visit, the general consent forms will not eliminate the statutory requirement for a provider to seek consent from an appropriately informed patient at the time the testing is planned.

Release of Medical Record Information

The revisions to Maine statute only affect the consent and counseling associated with HIV testing, and the delivery of this and related information to the patient who is tested. State and federal requirements and the related CMMF policies surrounding the release of HIV related information from the medical record are not changed with these revisions to Maine statute. Explicit consent for the release of HIV related information is required by law.

Recommendations for Healthcare Providers
  1. Provide HIV testing as part routine care according to CDC guidelines rather than the traditional risk-based approach.
  2. Revise operational procedures so that ordering providers routinely obtain verbal consent when they plan HIV testing.
  3. Eliminate the practice of obtaining separate written HIV consent before testing in most settings.
  4. Eliminate pre-test counseling when it is unnecessary.
  5. Revise and update computer systems to facilitate these changes and encourage providers to document consent or refusal in the record if appropriate.
  6. Continue to provide post-test counseling for subjects of positive HIV tests.

Resources and Links


Questions and Answers

Question: Why did we revise the Maine statutes with LD 429? Why not simply eliminate the requirement for HIV consent completely?

Answer: When the public hearings took place for LD429 in March 2007, members of CMMC medical staff and management staff were in attendance and provided supportive testimony for this bill to the subcommittee of the legislature. There were many different perspectives presented both in support of and in opposition to this change. These perspectives were presented by very credible parties with a wide array of interests. One common denominator for most everyone in attendance was that HIV testing should only be performed when a patient is properly informed and agrees to testing. Beyond that, most of the differences between those supporting and opposing this measure were based on how we can best insure that appropriate informed consent is obtained. In that respect, LD429 represents a compromise between those advocating a formal, written consent with lengthy counseling requirements and the other extreme of having no consent or counseling requirements whatsoever. We feel that the revised statute provides a very reasonable compromise and continues to insure appropriate consent and privacy with a much more streamlined operational approach for providers.

Question: If we incorporate wording in the general consent form for HIV testing consent, is that sufficient?

Answer: Probably not. This is currently under legal review. Remember, Maine statutes say, "An HIV test must be voluntary and undertaken only with a patient's knowledge and understanding that an HIV test is planned". As with most treatment and diagnostics, providers have an obligation to be sure that the patient is appropriately informed and involved in their treatment decisions. We believe that the only way to be certain that a patient has knowledge and consents to HIV testing, is for the provider to discuss this with the patient in an appropriate setting. As more information and legal opinions are rendered on this, operational procedures will be appropriately modified.

Question: Where can I get more information on this?

Answer: Check out the RESOURCES AND LINKS section of this website. There are lots of great resources for patients and healthcare providers. For those who need to explain the rationale for this testing be sure to check out: Discussion points for providers who plan HIV testing.

Question: In what types of patient practices should testing routinely be offered?

Answer: The CDC guidelines are probably a very good reference to address this question. In general routine testing may be more important in some clinical settings than others. Ultimately, providers should be aware of the CDC guidelines and apply them in the manner that is most appropriate for the situation. The bottom line is that the traditional risk-based approach to testing has not been as effective as necessary to effectively intervene in HIV infected patients. A broader approach to screening is necessary.

Question: There seems to be a stigma associated with HIV and even HIV testing. How do we deal with that?

Answer: This is absolutely true; stigma associated with HIV and HIV testing definitely is a problem and there is no simple solution to that. Over time, as HIV testing becomes more and more routine, we expect that stigma to eventually fade. Information and education is the best way to diffuse this. There are several great websites that attempt to "normalize" HIV testing. The KNOW YOUR STATUS website is a great example of a campaign that is focused on normalizing testing. Also, don’t be too quick to assume that all of your patients will be surprised if you suggest HIV testing. Many younger adults are well prepared, educated and eager to be tested.

Question: Most patients do not believe that they need to be tested for HIV. How should we deal with that?

Answer: The only way to know whether you are infected is to be tested for HIV. You cannot rely on symptoms alone because many people who are infected with HIV do not have symptoms for many years. Someone can look and feel healthy but can still be infected. In fact, one quarter of the HIV infected persons in the United States do not know that they are infected. Even if you think you have low risk for HIV infection, get tested whenever you have a regular medical check-up.




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Creatinine Decimal Precision

Rounding to tenths

As of November 11, 2007, we have changed the decimal precision for serum creatinine from hundredths back to tenths.

Background Information: In September, 2007, we changed serum creatinine to report to hundredths in an effort to reduce the error that rounding introduces in the eGFR equation. Soon after making this change, we received a number of comments from providers that this made the review of creatinine data more difficult and that the added precision in the creatinine was of limited clinical value. After weighing all of the pros and cons in the issue, we have decided to return the creatinine decimal precision back to tenths. Reference ranges will be rounded accordingly.

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Mumps Outbreak in Maine

Advisory - Important Information

The Maine CDC has announced a mumps outbreak in Southern and Central Maine. These confirmed cases are the first confirmed cases in Maine in over a decade. Maine CDC is advising physicians to be on the lookout for mumps symptoms and to collect samples for laboratory testing. Oral swabs for Mumps RT-PCR AND serum for Mumps IgM antibody should be submitted for testing. Sample collection instructions may be found on our website: Mumps Outbreak Alert 11-20-07 .

Follow this link Maine CDC Health Alert Network System (HAN) for more information from the Maine CDC.

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Coronary Risk Panel

Changes November 30, 2007

On November 30, 2007, all CMHC laboratories will convert to a new Coronary Risk Panel. This new panel configuration addresses several issues:

  • The reference ranges for Cholesterol, HDL and Triglyceride and the Interpretive Information have been modified to reflect the ATP III guidelines. These guidelines are found in the Interpretive Information section of this website.

  • The old Coronary Risk Panel included the Chol/HDL Ratio and a CHD Risk Interpretation. These details have been deleted and will no longer be reported in the new configuration. The ATP III guidelines shift much of the focus to the LDL and other risk factors that are clinically evaluated.

  • The LDL value in this panel is a calculated derivative that may only be reported if the triglyceride value is less than 400 mg/dL. In cases where this cannot be reported, the triglyceride will have an appropriate footnote to reflect the fact that the LDL cannot be calculated. Similarly, the HDL value, while this is a directly measured analyte, cannot be reported if the triglyceride value exceeds 600 mg/dL. These HDL values will be reported as “HI TRIG”.

  • An example of the interpretive information is provided below. This interpretive information will appear on a separate line in Millennium Powerchart for easier review.

    INTERPRETIVE INFORMATION FOR CORONARY RISK PANEL (Based on ATP III):

    LDL Cholesterol
    < 100 Optimal
    100-129 Near optimal/above optimal
    130-159 Borderline high
    160-189 High
    >/= 190 Very high

    Total Cholesterol
    < 200 Desirable
    200-239 Borderline high
    >/= 240 High

    HDL Cholesterol
    < 40 Low
    >/= 60 High

    ATP III identifies three categories of risk that modify the goals and modalities of LDL-lowering therapy. Risk determinants in addition to LDL-cholesterol include the presence or absence of CHD, other clinical forms of atherosclerotic disease, and the major risk factors including: cigarette smoking, hypertension, low HDL, family history of premature CHD and age.

    The NCEP ATP III summary report is available for review on the CMMC LabHelp website at: www.cmmc.org/cmmclab - Interpretive Information.

    The American College of Cardiology suggests that LDL-lowering treatment targets below 70 mg/dL may be appropriate in selected patients. (Class IIa recommendation).




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Chemistry Reference Ranges

Changes effective Dec 17, 2007

On Monday, December 17, 2007, several reference ranges for commonly ordered tests will be changed. This change is based on a "Normal Study" that was perfomed at CMMC. To view the list of changes, click this link.


Please feel free to contact a member of the pathology team if you have any questions on this.


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Troponin Change

Troponin Assay Change on February 7th

CMMC Laboratory will be converting the cardiac Troponin assay to a higher sensitivity method on February 7, 2008. This new assay is manufactured by Ortho Clinical Diagnostics Corporation and represents a significant improvement in sensitivity and low end precision over the previous assay.

Reference ranges for this new troponin assays will change. The new upper reference limit (URL) of 0.03 ng/mL is based on the 99th percentile of a normal population.

The following interpretive information will appear on test reports.

INTERPRETIVE DATA FOR TROPONIN-I:

Upper Reference Limit (URL).........less than or equal to 0.03 ng/mL

Myocardial injury is reflected by an increased troponin level above the 99th percentile of a normal reference population. Myocardial injury cannot be reliably ruled out until at least two successive samples, obtained over no less than 6 hours yield completely negative results.

Myocardial infarction is diagnosed when myocardial injury exists in the clinical setting of acute myocardial ischemia.

Increased troponin concentrations may be found in conditions other than AMI that can result in myocardial damage. These conditions include, but are not limited to: sepsis, congestive heart failure, hypertension with left ventricular hypertrophy, hemodynamic compromise, myocarditis, mechanical injury including cardiac surgery, defibrillation, chronic renal failure and cardiac toxins.



Additional Interpretive Information:

In the setting of a percutaneous coronary intervention (PCI), a PCI-related myocardial infarction may be considered when there is a troponin increase of greater than 3 x 99th percentile URL (0.10 ng/mL) in addition to clinical evidence of ischemia.

In the setting of coronary artery bypass grafting (CABG), a CABG-related myocardial infarct may be considered when there is a troponin increase of greater than 5 x 99th percentile URL (0.17 ng/mL) plus either new pathologic Q waves or new LBBB, or angiographically documented new graft or native coronary artery occlusion, or imaging evidence of new loss of viable myocardium.

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Rubella Test Change

Effective February 25, 2008

Rubella Antibody, IgG for immune status determination will change slightly due to a methodology change and updated testing guidelines. The qualitative result classifications will now be either: Negative, Low Positive or Positive. Our previous method identified an "Indeterminate" category for Rubella Antibody levels between 5-10 IU/mL. Results in this category will now be qualitatively classified as negative for immunity.

INTERPRETIVE INFORMATION FOR RUBELLA ANTIBODY, IGG will be as follows on test reports:

Negative - Less than 10 IU/mL - Patient is presumed to be not immune to Rubella infection.

Low Positive - Between 10 and 14.9 IU/mL - Antibody levels >/= 10.0 IU/mL are considered to be an indication of Rubella immunity.

Positive - Greater than/equal 15 IU/mL - Antibody levels >/= 10.0 IU/mL are considered to be an indication of Rubella immunity.

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Viral Hepatitis Panel Changes

New panel configuration

Viral hepatitis is an infection caused by one of five distinct viruses. The most commonly identified types in the United States are Hepatitis A virus (HAV), Hepatitis B virus (HBV), and Hepatitis C virus (HCV). All three viruses can cause acute illness characterized by nausea, malaise, abdominal pain, and jaundice. HBV and HCV can also produce chronic infections that are associated with an increased risk for chronic liver disease and hepatocellular carcinoma.

As of April 2008, CMMC laboratory will offer a panel of tests appropriate for the evaluation of acute or chronic Hepatitis B & C. This panel will be performed in-house.

Hepatitis B/C Panel:

  • Hepatitis B surface Antigen - HBs Ag
  • Hepatitis B core Antibody, Total - HBc Ab
  • Hepatitis C virus Antibody - HCV Ab


The following points should be noted:
  • For patients with risk factors that warrant screening for Hepatitis B and C, this new panel will reliably detect these infections in the acute, convalescent or chronic phase of the infection.

  • When serological findings indicate the presence of either Hepatitis B or C, supplementary testing is usually warranted. It is often most helpful to run confirmatory testing on new samples, however some confirmatory testing may be automatically reflexed on initial samples.

  • When HBs Ag tests are repeatedly reactive (weak positive reactions) confirmatory testing will be automatically reflexed from the initial sample for a neutralization procedure at our reference lab. These results will be footnoted that this reflexive testing has taken place. Confirmatory procedures will be reported separately.

  • The "Hepatitis B Profile, Chronic" profile is still available. This profile is only appropriate for patients known to be chronically infected with Hepatitis B.

  • For patients who are acutely ill with symptoms of viral hepatitis (elevated transaminases or jaundice and a well defined onset of symptoms) hepatitis A screening should also be considered. Hepatitis A antibody testing is not routinely included in the Hepatitis B/C profile but may be added as an individual order if clinically warranted. Again, Hepatitis A is a self limiting illness. The value of testing is primarily limited to a reduction of transmission to close contacts of the infected person, and epidemiologic surveillance. Hepatitis A testing is of little clinical utility after the resolution of the acute phase of the illness.

  • While uncommon in most populations in our region, other causes of hepatitis (non A, B, C) should be considered in cases when the index of suspicion for viral hepatitis is high. Patients with a history of Hepatitis B are at risk for Delta hepatitis or Hepatitis D infection (a superinfection or co-infection). Hepatitis E, while uncommon in the US and usually self-limiting, is endemic in some parts of the world. Travelers from endemic areas require consideration of this causative agent. Hepatitis E is associated with high mortality in pregnant females during the third trimester.

  • The Acute Hepatitis Panel that was previously offered through our reference laboratory will no longer be orderable.

  • Ambiguous and/or redundant orders for hepatitis testing will not be processed. Samples may be collected and held, if appropriate, until more definitive orders are submitted in written form. Examples of ambiguous orders include requests such as: Acute and Chronic Hepatitis Profile (as one order) and Hep ABC. Providers should seek clinical consultation from the pathology staff when necessary.


Viral Hepatitis Resources:

  1. For a full listing of hepatitis related tests available at CMMC, Click here and search under the term “hepatitis”
  2. CDC Online Tutorial: VIRAL HEPATITIS SEROLOGY: HEPATITIS A – E
  3. CDC Hepatitis Home Page
  4. WHO Hepatitis Home Page
  5. New England Journal of Medicine: Hepatitis E Vaccine — Ready for Prime Time?
  6. CDC Hepatitis E Slide Tutorial (Six Slides)
  7. CDC: Interpretation of the Hepatitis B Panel
  8. Maine Public Health Alert: Acute Hepatitis B in Maine, 2006-2007





Matthew T. Twomey, MT(ASCP)

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Semen Analysis Changes

As of April 28, 2008, the CMMC Laboratory will no longer be performing the Semen Analysis Procedure.

The Central Maine Fertility Center at 287 Main St., Suite 201, in Lewiston will continue to perform this analysis. We recommend that patients in need of this procedure, call the fertility coordinator, Louise Michaud, at the Fertility Center at 795-7180 or 795-5787 or toll free at 800-978-0315 to schedule an appointment.

Please be advised that an appointment must be made before any specimen for analysis is collected and delivered to the Fertility Center. Specimens that arrive without an appointment will not be tested.

The CMMC laboratory will continue to evaluate post vasectomy specimens for the presence of sperm.

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A Tribute to Our Volunteers

Thanks to all the wonderful volunteers who cheerfully help us out in the laboratory. Your dedication and commitment to our organization is heart-warming! Even when the snow is deep and the weather doesn't cooperate, you folks are always here to help. We appreciate that!

To all the volunteers who help deliver lab samples - Thank you!

To Richard and Herb who file slides in histology - Thank you!

To Matt for all the help with the website - Thank you!

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Newborn CF Screening

New Cystic Fibrosis Newborn Screening

Overview
As of July 1, 2008, the state of Maine will adopt a new cystic fibrosis screening for newborns that will help to diagnose and treat the disease at a much earlier age. Advances in technology, research showing improved outcomes, and increased public awareness have led to this program. Prior to this initiative, testing for CF has primarily been carried out after patients became symptomatic, resulting in late diagnosis and complications. The new screen will measure immunoreactive trypsin (IRT). An elevated IRT result will trigger a DNA test to identify presence of 39 common CF mutations. Traditional sweat chloride testing will be used to confirm positive screens. The objective is to identify all cases of CF, with as many pre-symptomatic diagnoses as possible. This will reduce and help manage future complications of CF. Earlier detection improves patients’ overall health and lowers medical expenses.

Methodology
Using the same sample that is currently used for newborn metabolic screening, newborns will be screened for IRT. If the IRT is low, the screen is negative. Conversely, if the IRT is elevated, DNA testing is performed. The DNA assay has the ability to identify 39 common genetic mutations that are responsible for CF. A positive result means that the infant is at increased risk of CF. The specific risk is dependent on the exact category of positive screen as indicated below.
  • Category C: IRT >95th percentile and two mutations detected. The infant most likely has CF.
  • Category B: IRT >95th percentile and one mutation detected. The infant has about a 1/30 chance of CF. A confirmatory sweat test will separate these infants into two groups:
    • CF Diagnosis - Infants who have a second mutation that is not included in the newborn screen DNA assay
    • Unaffected carrier - Infants whose diagnostic test shows them to be unaffected
  • Category A: IRT >99.9th percentile and no mutations detected. The infant has a <1/100 chance of CF.
    • Because the infant's IRT result is so high, it is possible that the infant may be affected with two abnormal CFTR mutations that are not included in our screen.
    • Perinatal stresses can also cause high IRT levels.
All positive screens require a sweat chloride test at a CF Foundation accredited sweat lab to confirm the diagnosis. Sweat tests cannot be done until babies are at least two weeks old, term; or two kg in weight to assure enough sweat to give a reliable result.

Estimated Timeline for Receiving a Positive CF Screen
  • Day 1 – birth date of baby
  • Day 5-7 – positive screen reported by phone and faxed to primary care provider (PCP) and Genetics office
  • Day 5-7 – Genetics office schedules sweat test
  • Day 14 – two week checkup with provider; parents are counseled by provider and scheduled to see a Genetic counselor
  • Day 15 – sweat test confirmation and genetic counseling completed; all babies confirmed to have CF will be referred to a CF Center for evaluation and treatment

Provider Procedure
When a positive screen is reported, the provider will contact genetics at MMC or EMMC to arrange for the sweat test and genetic counseling. The provider faxes the order form to the laboratory that will perform the confirmatory sweat test. The provider should discuss the results of the positive screen with the parents at the two-week check up. The baby should be assessed for malabsorption and respiratory problems; any questions will be directed to the CF Center in Portland. Next, the confirmatory sweat test and genetic counseling will be completed and reported to the ordering provider. The provider will inform the family of the results. If CF is confirmed, the provider will then refer the child to the CF Center.

Projected Outcome
As a result of this new procedure, an estimated 50 babies per year will have a positive screen requiring a sweat chloride test. Of these, it is estimated that five or six babies will be identified with CF each year through this screening program. The new screening will promote proactive rather than reactive practice. Although there is no cure for CF, an early diagnosis combined with aggressive therapy and treatment options can meaningfully improve the quality of life for CF patients.

Resources
For more information regarding cystic fibrosis and/or its new screening for newborns, the following resources are available for families and practitioners.



Written by Matthew Levasseur and Mike Kelly, with great appreciation for assistance from Ellie Mulcahy and Matthew Twomey

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NT-proBNP

Beginning July 28, 2008,CMMC laboratory will replace the BNP test with NT-proBNP. NT-proBNP is one of two well established peptides of cardiac muscle origin, BNP being the other. BNP and NT-proBNP provide similar information regarding the development of congestive heart failure (CHF).

BNP is an active natriuretic and diuretic peptide hormone. NT-proBNP is a hormonally inactive peptide which is secreted in an equimolar amount as BNP in response to neurohormonal or mechanical stimulation. Both have been used with other cardiac markers to stratify risk in coronary syndromes and they may also be useful in the emergent discrimination of heart failure from non-cardiac causes of dyspnea.

Assay values of both BNP and NT-proBNP are age dependent; both increase as renal function declines. Both are good markers for the diagnosis and prognosis of CHF. Numeric values for the two assays are significantly different.

The following interpretive information will appear on NT-proBNP reports:

Interpretive Information for NT-proBNP:

<50 Years of Age:
  • <300 pg/mL – heart failure unlikely
  • 300-450 pg/mL – heart failure possible
  • >450 pg/mL – heart failure likely

50+ Years of Age:
  • <300 pg/mL – heart failure unlikely
  • 300-900 pg/mL – heart failure possible
  • >900 pg/mL – heart failure likely


NT-proBNP is more stable than BNP; consequently, sample stability is considerably improved with NT-proBNP. NT-proBNP will be automatically substituted for all BNP orders. BNP will remain available by special order for a limited time with pathologist consultation.

Additional Interpretive Information:



NT-proBNP Values in Patients with CHF by NYHA Functional Class
AllNYHA INYHA IINYHA IIINYHA IV
Mean21241299146733902956
Median121074191718701665
5th Percentile10913785191260
95th Percentile719329234514105848993

For detailed technical assay information, CLICK HERE.
For sample collection requirements, CLICK HERE.

Written by John W. Skinner, MD

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Sequential Troponin Profile

Assessment of Acute Myocardial Infarction

Written by Matthew T. Twomey, MT(ASCP) August 8, 2008 As of Monday, September 8, 2008, a new myocardial marker profile will be introduced for the diagnosis and evaluation of acute myocardial infarction. Troponin Profile will consist of sequential Troponin-I determinations at timed intervals. When ordered, samples will be collected immediately (baseline), with subsequent samples collected at three and six hours after the initial order. Troponin-I will be analyzed using the current high sensitivity method that was introduced in February, 2007 (CLICK here to view related article). The current Myocardial Profile consists of a sequence of samples collected at baseline, 3 hours, 6 hours and 12 hours; samples are analyzed for Troponin-I and total CK with reflexive determinations for CK-MB. As of September 8, 2008, all order sets that are routinely used for evaluation of myocardial infarction/injury will be changed to reflect the new Troponin Profile. CK and CK-MB will no longer be included in the profile. Clinicians may add additional tests to the Troponin profile order set as needed. Order sets that include the Troponin Profile will include optional (unchecked) orders for 9 hour and 12 hour samples for troponin. While this is not normally required in routine assessment of myocardial infarction, additional orders may be selected if clinically warranted. This change builds upon a number of improvements that have been introduced in the past year at CMHC laboratory facilities for the assessment of myocardial injury. In February, 2008, CMMC Laboratory introduced the high sensitivity troponin assay on the Vitros EciQ analyzer (Ortho Clinical Diagnostics). In July, 2008, Rumford and Bridgton Hospitals introduced the same troponin assay on the Vitros EciQ in an effort to enhance and standardize the troponin assay across all CMHC laboratories. These changes bring our laboratories into close alignment with recommendations made in the expert consensus document by the Joint ESC/ACCF/AHA/WHF Task Force for the Redefinition of Myocardial Infarction1. More importantly, these changes have improved the sensitivity, specificity and timeliness of myocardial marker measurements at the CMHC laboratories in an effort to provide state of the art cardiac services to our patients.

Summary

When this change is implemented, the following important points should be noted:

  • TROPONIN PROFILE is now the routine profile for the assessment of myocardial injury/infarction.
  • Troponin samples will be collected at baseline, 3 and 6 hours. All order sets that contained the traditional Myocardial Profile will be changed to include the Troponin Profile instead.
  • Additional sample collection times must be explicitly ordered by the clinician. At times it may be appropriate to add an additional timed sample at 9 - 12 hours for troponin analysis.
  • Total CK and/or CK-MB determinations may be ordered individually or in sequence as required, but must be explicitly ordered by the clinician.
  • CK-MB will no longer be performed reflexively based on the Total CK level. All orders for CK-MB must be explicitly ordered by the clinician.
References
  1. Thygesen, Kristian. Universal Definition of Myocardial Infarction. European Heart Journal 2007;28:2525-2538.



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HIV Testing

Integrating HIV Testing Into Routine Care

Matt Twomey, LIS Manager at CMMC, delivered a presentation at the annual fall Northeast Laboratory Conference in Portland, Maine. The presentation focused on Integrating HIV Testing Into Routine Care and the use of the Ortho Vitros HIV 1,2 Antibody test.

To download a copy of the presentation, click this link.









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AABB Presentation

Johanna Ward Presents at AABB

Written by Matthew T. Twomey, MT(ASCP) October 23, 2008


Johanna Ward, Transfusion Services Manager at CMMC, presented a poster at the 2008 AABB Annual Meeting held in Montréal this October. The presentation described "A Collaboration between The American Red Cross and Central Maine Medical Center" to establish a Blood Donation Center.

To download a copy of the poster presentation, click this link.





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Influenza A/H1N1

CMMC Laboratory has received a number of calls and questions related to the recent influenza outbreak. The most accurate and up-to-date information is available from Centers for Disease Control and Prevention (CDC) websites: US CDC H1N1 Influenza and Maine CDC Home Page .
Testing for influenza is available through Maine’s CDC laboratory, the Health & Environmental Testing Laboratory (HETL) in Augusta, Maine. CMMC laboratory will refer samples to the HETL for testing as appropriate.
Collect TWO SWABS for all influenza testing - All samples submitted for routine influenza testing should include TWO SWABS in the event that follow-up testing at the HETL is required. Updated collection instructions are provided on the CMMC LabHelp website: Influenza Sample Collection
Additional testing performed at the HETL will be reported separately.







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Bactec FX Blood Culture System

Bactec Upgrade LIVE December 22, 2009

Written by Matthew T. Twomey, MT(ASCP) December 22, 2009

As of Tuesday, December 22, 2009, our blood culture analyzer will be upgraded to a Bactec-FX System. This instrument uses the same technology for rapid detection of positives as our older Bactec analyzer. Collection techniques and culture media will be identical with this upgrade.

Negative Culture Reporting Intervals
The new analyzer will be interfaced to the laboratory information system. This will facilitate automated reporting of negative blood cultures. For negative blood cultures, you will now see microbiology reports in the electronic medical record according to the following schedule:
  • 1 hour - Blood culture In-progress
  • 12, 24, 36, 48 hours - Preliminary negative
  • 3, 4 days -Preliminary negative
  • 5 days - Final negative
  • If cultures are held for longer intervals, additional preliminary negative reports will be issued at 7 and 14 days, with a final report at 21 days.

Positive Culture Reporting
Positive blood cultures are defined as critical findings. Positives will be immediately reported to the appropriate patient care area and immediately posted in the electronic medical record.







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Bordetella pertussis Testing

Bordetella cultures temporarily unavailable

Due to numerous outbreaks of Bordetella pertussis currently thoughout Maine, testing demand has increased significantly for Bordetella pertussis at the state public health lab. In order to increase sample throughput and provide more timely results for clinicians, HETL will temporarily suspend offering Bordetella cultures effective immediately. The polymerase chain reaction (PCR) test method will be used routinely for all samples. While culture is important early on in identifying outbreaks, the PCR method provides superior senstivity, turnaround time and does not require the use of specialized culture media. HETL will resume offering culture to clients when specimen volume returns to baseline levels. June 6, 2012

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Digoxin Sample Requirements

Plasma samples are no longer accepted

Heparin plasma sample will no longer be accepted for quantitative analysis of digoxin. The CMMC Laboratory was recently notified by the manufacturer that analysis of heparinized plasma samples of digoxin using the Ortho Diagnositics product VITROS DGXN may give falsely elevated levels. If a heparinized plasma sample is used, the false positive bias may be sufficient to indicate incorrectly that the patient is in the therapeutic range for digoxin. If a serum sample is used, assays results are unaffected. Heparinized plasma samples will be rejected and a request for a serum sample will be made.

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Retic Reference Range Change

Reticulocyte Standardization

In order to facilitate the standardization of reticulocyte counts derived from various automated methods and the manual method, the instruments used at Central Maine Medical Center have been recalibrated. This recalibration results in a change in our reference range for patient greater than six months. Ranges for newborns through six months of age have not changed.

Reticulocyte Reference Range:

  • 0 – 1 day: 1.8 – 4.6%
  • 1 – 7 days: 0.1 – 0.9%
  • 1 – 4 wks: 0.3 – 0.9%
  • 1 – 2 mos: 0.3 – 2.2%
  • 2 – 6 mos: 0.5 – 1.9%
  • > 6 mos & Adults: 0.6 – 2.0%








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