Double false-negative traps in urine routine test: a case report

Xiang Qian,Hanyu Liang,Zhen Ren

doi:10.1515/labmed-2019-0206

Abstract

Abstract Background Urinalysis is one of the most commonly performed tests in clinical practice and supplies important information for a series of clinical conditions, including renal and urinary tract diseases. The clinical laboratory often completes urinalysis through the combined use of urinary dry-chemistry and formed-element analyzers. Urine red blood cell (RBC) morphology test is often used to discriminate the source of hematuria by manual microscopy. Case presentation In this case report, we describe a 39-year-old woman with chronic glomerulonephritis (CGN) who underwent both urine routine test and RBC morphology test. Her RBC count was in the normal range and the occult blood test was negative in routine test, while the RBC morphology test indicated the presence of non-homogeneous hematuria. Conclusions Therefore, we analyzed the causes of false-negative result on the urine chemical analyzer and the automatic microscope system, respectively.

Highlights

Chemical and microscopic testing of urine samples, known as urinalysis, is one of the most important routine tests in clinic
Case presentation: In this case report, we describe a 39-year-old woman with chronic glomerulonephritis (CGN) who underwent both urine routine test and red blood cell (RBC) morphology test
Her RBC count was in the normal range and the occult blood test was negative in routine test, while the RBC morphology test indicated the presence of non-homogeneous hematuria

Summary

Introduction

Chemical and microscopic testing of urine samples, known as urinalysis, is one of the most important routine tests in clinic. It is mainly used for the diagnosis, differential diagnosis, treatment monitoring and health. Chronic glomerulonephritis (CGN) is a group of glomerular diseases with proteinuria, hematuria, hypertension and edema as the basic clinical manifestations. The onset way of CGN is different and the disease progress is slow. CGN can have varying degrees of renal function decline. With a tendency to deterioration of renal function, it will eventually develop into chronic renal failure [1].

Case presentation

Chemical method

Findings

Discussion