NEUTROPHIL ENZYMES IN URINE FOR THE DETECTION OF URETHRAL INFECTION IN MEN

Objectives-To determine if assaying the neutrophil enzymes, neutrophil elastase (NE) and myeloperoxidase ((MPO) in the urine of men attendin g a genitourinary medicine clinic could identify those with Neisseria gonorrhoeae or Chlamydia trachomatis infections, and those with urethr itis (with or without an identified infection with either organism), a nd to compare the new assays with the performance of the leucocyte est erase test (LET). Method-100 men had urethral specimens taken for Gram -stained urethral smear, culture for N gonorrhoeae, and for C trachoma tis testing by enzyme immunoassay. First-voided urines were tested for leucocyte esterase by commercial dipstick (positives were defined as greater than ''trace'') and then frozen at - 20 degrees C prior to bei ng assayed for NE and MPO. Results-Five patients had gonorrhoea, six h ad chlamydia and none had both. Evidence of urethritis (> 5 polymerpho nuclear leucocytes in four x 1000 fields) was found in 29 men. The res ults of the urine assays showed MPO levels to be non-discriminatory; h owever NE levels were significantly elevated in patients with proven i nfection or urethritis or both. Using NE values from men with no infec tion or urethritis an upper limit for normal was defined. Utilising th is, the sensitivity of the elastase assay was calculated and found to be superior to the sensitivity of LET for detecting proven infection ( 64% vs 36%) and urethritis (52% vs 31%). Conclusions-Further studies o f neutrophil elastase in the pathogenesis, diagnosis and treatment of urethritis are indicated.