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[Findings obtained by the analyses of unexpected abnormal laboratory data]
1Kita-Fukushima Medical Center, Date.
Insights
Laboratory staff play a crucial role in identifying unexpected clinical laboratory data. Understanding the causes of these anomalies, such as false negatives in fecal occult blood tests and elevated potassium levels, is vital for accurate patient diagnosis.
Area of Science:
- Clinical Laboratory Medicine
- Biochemistry
- Immunology
Context:
- Clinical laboratory medicine lectures often highlight unexpected findings.
- Laboratory staff are the primary identifiers of unusual laboratory data.
- Real-world case studies demonstrate common laboratory errors and their causes.
Purpose:
- To analyze and explain various causes of unexpected laboratory data.
- To emphasize the importance of vigilance and understanding in laboratory diagnostics.
- To provide practical insights for laboratory professionals and physicians.
Summary:
- Discusses common causes of erroneous laboratory results, including false negatives in fecal occult blood tests due to toilet sanitizers, elevated serum potassium from cold-stored blood, false positives in ELISA from aggregated IgG, panic values from EDTA blood regurgitation, and low values from unmixed serum.
- Examines the precision of bleeding time measurements and variations in capillary blood glucose levels across different body sites.
- Highlights the practical importance of investigating and understanding the origins of unexpected laboratory data for quality assurance.
Impact:
- Enhances awareness among laboratory staff and physicians regarding potential sources of error.
- Promotes improved quality assurance protocols in clinical laboratories.
- Contributes to more accurate and reliable diagnostic testing, ultimately benefiting patient care.
Abstract:
As the final lecture of Clinical Laboratory Medicine in Fukushima Medical University, I showed some of our findings obtained by the analyses of unexpected laboratory data. Most of these unexpected or unusual data were first noticed by laboratory staffs in charge. Items mentioned were; 1) false negative reaction of immunological fecal occult blood test, induced by the contact of hemoglobin with toilet sanitizers or detergents, 2) highly elevated serum K level, induced by the cold storage of whole blood, 3) false positive reactions in ELISA, induced by the aggregated IgG developed by the heat-pretreatment of sera, 4) panic values developed by the regurgitation of EDTA blood, 5) markedly low values due to the non-mixing of frozen thawed serum sample, 6) precision of the bleeding time in earlobes, and 7) differences in capillary blood glucose levels among forearm, palm and fingers. In the analyses of 6) and 7), the methodology of quality assurance could be introduced, although we realized the difficulty in examining in our physical body. Every issue examined is practically important, and laboratory staffs including physicians should pay more attention on the unexpected laboratory data and know why and how the data are produced.
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