Editor: Frederick L. Kiechle, MD, PhD
Submit your pathology-related question for reply by appropriate medical consultants. CAP TODAY will make every effort to answer all relevant questions. However, those questions that are not of general interest may not receive a reply. For your question to be considered, you must include your name and address; this information will be omitted if your question is published in CAP TODAY.
Q. Which gynecological slides can cytotechnologists report?A. The CAP cytopathology checklist requirement CYP.07465 “Pathologist Interpretation” states that the following categories of gynecologic cytology slides must be reviewed and interpreted by the pathologist:
- Malignant or suspicious for malignancy
- Low- and high-grade squamous intraepithelial lesions
- Atypical squamous cells
- Atypical glandular cells
- Reactive or repair
The laboratory’s written policy must define the types of slides or categories that must be referred to a pathologist for review and reporting. The policy must include all of the gynecologic categories listed in CYP.07465 as well as any other limitations if required by the laboratory. In addition, all nongynecological cases must be reviewed by a pathologist as required in CYP.05332 “Report Review.”
The CLIA regulation 42 CFR 493.1274(e) provides additional information.
Dawna Mateski, MT(ASCP)
Checklist Customization Analyst
CAP Accreditation Programs
Q. Is it recommended that a hospital streamline its reference ranges for point-of-care and main laboratory tests? For example, should our normal ranges be the same for Cobas blood gas and i-Stat blood gas parameters? Should we program the same ranges in our i-Stat hemoglobin and hematocrit as we use for our hematology analyzers, including pediatric ranges? Is it more important to use manufacturers’ ranges (verified in 20 male and 20 female volunteers, when practical) or to keep the ranges concordant between different areas of the hospital?A. There are no requirements that an institution use the same reference intervals across all analyzers. Sharing reference intervals between POC and the central laboratory makes interpretation easier for clinicians, as they need to keep only one range in mind when reviewing either POC or central laboratory results. However, POC technologies are very different than central laboratory methods and there may be analytical biases between specific platforms that preclude adoption of one shared reference interval across all patient populations in a hospital.
Consider that hemoglobin/hematocrit on central laboratory analyzers is a spectrophotometric determination of hemoglobin while the i-Stat utilizes conductivity to measure hematocrit and calculates the hemoglobin result mathematically. In open heart and trauma surgery patients with multiple transfusions and volume replacement, hemoglobin measured in a central laboratory may not match hematocrit measured on an i-Stat because of the effects of the transfusion and protein replacement on conductivity measurements. The i-Stat offers a cardiopulmonary bypass mode to attempt to correct for this bias, but this can multiply the bias depending on the actual hemodilution of the patient, and studies have recommended that spectrophotometric methods be used to estimate hemoglobin in these cases.
Conducting correlation studies across platforms using the same sample set at least every six months from typical patient populations in the hospital can indicate whether biases are present and whether a common reference interval can be adopted. Consider the limitations of each method and the frequency with which such biases could arise when laboratories share a common reference interval across methods and, most important, discuss these issues with your clinical leaders.
Hopfer SM, Nadeau FL, Sundra M, Makowski GS. Effect of protein on hemoglobin and hematocrit assays with a conductivity-based point-of-care testing device: comparison with optical methods. Ann Clin Lab Sci. Winter 2004;34(1):75–82.
James H. Nichols, PhD, D(ABCC), Professor of Pathology, Microbiology, and Immunology
Medical Director, Clinical Chemistry and Point-of-Care Testing
Vanderbilt University School of Medicine
Member, CAP Instrumentation Committee