Laboratory Testing

Introduction

Certain infections can be detected or diagnosed within clinics or surgeries but others require microbiological services, also essential for confirmatory and antimicrobial sensitivity testing. If on-site microscopy is unavailable, the use of air-dried swabs sent for laboratory staining and microscopy should be considered. This is applicable for vaginal discharge (e.g. bacterial vaginosis, candidiasis) and also for male urethral discharge for polymorphonuclear leucocytes (PMNLS) indicating urethritis and Gram negative intracellular diplococci, which are highly suggestive, but not diagnostic of gonorrhea.

The optimum minimum time to take swabs for screening from asymptomatic patients following a specific incident has not been established. The timing of serological tests should take into consideration the ‘window periods’ of the respective infections. Final exclusion tests must be advised at the end of this time. Baseline assays soon after the incident is useful especially if subsequent repeat tests are positive.