Diagnostic yield of early morning urine samples in the diagnosis of tuberculosis

摘要

Early morning urine (EMU) samples are sent in significant numbers from patients suspected of having tuberculosis (TB), despite evidence that the diagnostic yield is very low.1 We assessed the diagnostic yield of EMUs and calculated the associated workload, by retrospectively analysing data from our institution from January 2000 to June 2004. All patients with positive urine cultures for Mycobacterium tuberculosis (MTB) were identified from microbiology records, and medical notes were reviewed. The cost of processing each EMU sample was calculated using the Welcan schedule of time-based unit values for quantifying pathology workload.