Manual microscopy outperforms automated urine analysis, according to a small study presented at the National Kidney Foundation’s 2014 Spring Clinical Meetings (Las Vegas; April 23-26). Automated urinalysis underreported the value of granular casts in a cohort of acute kidney injury (AKI) patients, a key determinant of the underlying cause of kidney damage. The researchers compared results in the reported ranges of granular and muddy brown casts using manual microscopy and an automated urine analyzer (IRIS 200 system) for evaluation of 10 samples from patients with acute kidney injury. A single observer analyzed the same urine sample with both technologies, spending an average of 10 minutes per patient specimen. An attending physician validated the first count. Manual counts were divided by 144 to approximate the automated system’s high-power focus (HPF). Results were characterized by number of casts as none, few (0 to 5 casts/HPF) and many (21 to 50 casts/HPF). The researchers found that there were significant differences between the results produced by each modality. Manual microscopy coded no patient as having “none,” while the automated system coded 70 percent as “none.” Manual analysis coded 100 percent of specimens as “few.” The automated system coded two samples as “many,” which manual […]