Science Manual Urine Microscopy Versus Automated Urine Analyzer Microscopy in Patients with Acute Kidney Injury Natasha Sharda, MD, Omid Bakhtar, DO, Bijin Thajudeen, MD, Ed Meister, PhD, Harold Szerlip, MD* Lab Med Fall 2014;45:e152-e155 DOI: 10.1309/LMVJK6W4KQL1ZHKS
ABSTRACT Objective: To examine whether a significant difference exists between the reported ranges of granular and muddy brown casts in urine specimens using manual microscopy compared with an automated urine analyzer in a cohort of patients with acute kidney injury (AKI). Methods: Freshly voided urine specimens from 25 consecutive patients who were under evaluation by the Department of Nephrology for AKI were simultaneously examined using the iQ200 automated microscopy system and manual microscopy performed by a trained observer. We coded the results according to the number of pathological casts identified and performed a 3 × 2 Freeman-Halton extension of the Fisher exact probability test. Analysis of urine for diagnostic purposes dates back to ancient times. For many centuries, visual inspection of the urine was considered as important as palpation of the pulse in diagnosis.1,2 During the Middle Ages, numerous quacks and charlatans practiced “pisse prophecy,” claiming to be able to tell patients’ fortunes based on examination of their urine. In 1637, Thomas Brian exposed these excesses in a famous monograph.1,3 In his seminal early 20 th century work, Thomas Addis conclusively established identification of formed elements in the urine as a key component for the diagnosis of renal disease.4 The presence of
Abbreviations RBCs, red blood cells; WBCs, white blood cells; AKI, acute kidney injury; RIFLE, risk, injury, failure, loss, and end stage; AKIN, Acute Kidney Injury Network; LPFs, low power fields Department of Internal Medicine, Division of Nephrology, University of Arizona College of Medicine, Tucson, AZ *To whom correspondence should be addressed. [email protected]
e152
Lab Medicine Fall 2014 | Volume 45, Number 4
Results: Overall, the number of casts identified via manual microscopy differed significantly (P
ABSTRACT Objective: To examine whether a significant difference exists between the reported ranges of granular and muddy brown casts in urine specimens using manual microscopy compared with an automated urine analyzer in a cohort of patients with acute kidney injury (AKI). Methods: Freshly voided urine specimens from 25 consecutive patients who were under evaluation by the Department of Nephrology for AKI were simultaneously examined using the iQ200 automated microscopy system and manual microscopy performed by a trained observer. We coded the results according to the number of pathological casts identified and performed a 3 × 2 Freeman-Halton extension of the Fisher exact probability test. Analysis of urine for diagnostic purposes dates back to ancient times. For many centuries, visual inspection of the urine was considered as important as palpation of the pulse in diagnosis.1,2 During the Middle Ages, numerous quacks and charlatans practiced “pisse prophecy,” claiming to be able to tell patients’ fortunes based on examination of their urine. In 1637, Thomas Brian exposed these excesses in a famous monograph.1,3 In his seminal early 20 th century work, Thomas Addis conclusively established identification of formed elements in the urine as a key component for the diagnosis of renal disease.4 The presence of
Abbreviations RBCs, red blood cells; WBCs, white blood cells; AKI, acute kidney injury; RIFLE, risk, injury, failure, loss, and end stage; AKIN, Acute Kidney Injury Network; LPFs, low power fields Department of Internal Medicine, Division of Nephrology, University of Arizona College of Medicine, Tucson, AZ *To whom correspondence should be addressed. [email protected]
e152
Lab Medicine Fall 2014 | Volume 45, Number 4
Results: Overall, the number of casts identified via manual microscopy differed significantly (P
