Factitious Biochemical Measurements Resulting From Hematologic Conditions

Bakul I. Dalal, MD, FRCPC; Malcolm L. Brigden, MD, FRCPC


Am J Clin Pathol. 2009;131(2):195-204. 

In This Article

Abstract and Introduction


Factitious laboratory results often lead to unnecessary testing or treatment. This brief review of factitious biochemical results due to preexisting hematologic conditions focuses on the mechanisms underlying the factitious results and suggests ways to prevent them. An observant pathologist identifies these errors, intervenes in a timely fashion, investigates the sources of error diligently, and institutes measures to prevent their recurrence.


A significant number of laboratory results and reports are factitious[1–4] or misinterpreted by clinicians and other laboratory clients.[5] Such mishaps may lead to unnecessary diagnostic evaluation[6] and/or unwarranted therapeutic interventions.[6–9] On the other hand, an astute observer may identify the factitious nature of a result and investigate it to diagnose an underlying serious condition.[10–12]

The sources of factitious laboratory results may be preanalytical, analytical, or postanalytical factors. The preanalytical factors are in vivo causes, such as preexisting disease conditions and medications, and in vitro causes, such as problems with sample collection, type of sample tube, anticoagulant and ambient conditions, and duration of storage and transport.[13,14] Recent fiscally driven efforts at centralization of laboratory facilities mean longer transportation times, while the batching of laboratory tests leads to longer storage times. The analytical factors are instrument and method-related issues, specifically the advanced automation of clinical laboratories and the lack of human intervention before the results are released. Lastly, the postanalytical factors are human errors in transcription of results and comprehension[5] and interpretation of reports.

Larger clinical laboratories are conventionally subdivided into hematology, chemistry, microbiology, anatomic pathology, and so on. The testing is done by specialized technologists who are competent in identifying and correcting errors in their own subspecialties but not outside their field of expertise. This article bridges that gap by reviewing the factitious biochemical measurements that arise as a result of hematologic conditions and factors Table 1 . The artifacts are classified by hematologic conditions and their mechanisms and prevention are discussed.