Isolation of Haemophilus influenzae and Haemophilus parainfluenzae in urethral exudates from men with acute urethritis: a descriptive study of 52 cases.

ABSTRACT

OBJECTIVES: To describe the clinical characteristics and therapeutic outcomes from male patients diagnosed of Haemophilus spp urethritis. METHODS: A chart review of patients who presented to our hospital from January 2013 to December 2014 with symptoms of acute urethritis in which Haemophilus spp was isolated in their urethral samples was performed. RESULTS: Haemophilus spp was isolated in 52 out of 413 urethral samples (12.6%) received in our laboratory from patients with symptoms of acute urethritis during the study period. Seven cases corresponded to Haemophilus influenzae and 45 cases to Haemophilus parainfluenzae. The most common clinical presentation was mucopurulent urethral discharge (71%). Eight per cent were HIV-infected patients, and 60% were men who have sex with men. Haemophilus spp was isolated as a single pathogen in 6.8% (28 of 413) of cases. Seventeen per cent of Haemophilus spp were ß-lactamase producers. All patients reported having practiced unprotected insertive oral sex the month before consultation, and five of them denied having had another sexual contact apart from this exposure. In all cases in which follow-up was available, empirical treatment achieved a complete clinical resolution. CONCLUSIONS: Haemophilus spp was considered a pathogen in at least 6.8% of the patients from the evaluated area. It affected men regardless their sexual orientation or HIV status. Unprotected oral sex could play a role in its transmission. The limitations of the study (small sample size and lack of a representative control group) do not allow to prove the true pathogenic role of Haemophilus spp in acute urethritis.