Background Nucleic acid amplification tests (NAATs) to detect Neisseria gonorrhoeae (GC), allow less invasive sampling and are more sensitive than culture. Aptima combo 2 (AC2) has a high specificity but positive predictive value can be low in low prevalence populations. GC diagnoses may be lower in an integrated family planning (FP) and genitourinary (GU) clinic compared to those primarily providing GU care.
Aim To investigate whether the introduction of GC NAATS into an integrated clinic has increased rates of GC screening and detection.
Methods All patients having a GC screen 4 months prior to and following NAATS introduction were identified by laboratory databases. Notes were reviewed for those diagnosed with GC. Information regarding patient demographics, symptoms and risks were gathered (see abstract P45 table 1).
Results Pre-NAATS: 2307 symptomatic and asymptomatic patients were screened with GC culture of which 20 (0.87%) were positive. Post-NAATS: 3444 symptomatic and asymptomatic patients were screened with AC2 of which 43 (1.25%) were confirmed positive for GC. 217 of the symptomatic patients were also cultured and 18 (8.3%) were positive. Of the 43 positive NAATS tests, 20 patients were also culture positive; 10 were culture negative, 1 grew Neisseria meningitidis (isolated in the throat) and 12 had no culture taken. All of the NAATs positive, culture negative individuals had symptoms, signs or high risks for GC. All patients with positive cultures were NAATS positive.
Conclusions Following the introduction of NAATS, the proportion of patients attending clinic who were screened for GC significantly increased and the number of GC diagnoses doubled. This may be due to better acceptability and uptake of screening, including those attending for FP care. NAATs identified more cases of GC than culture alone. There was only one case of a possible false positive. This provides reassuring data to support use of NAATS in this setting.