Is sterile pyuria another minor diagnostic criterion in urinary tuberculosis?

Composite reference standard (CRS) is used for diagnosis of urinary tract tuberculosis (UTB). We examined if addition of a new 'component test' as minor criterion in the form of SP could improve the yield.

We identified patients admitted with a diagnosis of UTB from January 2009 to February 2016 from our patient database. We performed the validation of addition of a new 'component' "sterile pyuria" to the existing basic CRS.

SP was seen in 50 patients (65.7%). Forty (52.6%) of these patients had one major criterion positive and 10 (13.1%) were diagnosed based on minor criteria. If SP was added as a minor criterion, an additional 8 (9.2%) patients would have been diagnosed based on minor criteria alone without the need for a histopathology.

SP could improve the diagnostic yield of existing CRS by 8% with a 70% decrease in reliance on histopathology for diagnosis.