Background BASHH guidelines recommend routine test of cure (TOC) for gonorrhoea by nucleic acid amplification technique (NAAT) 2 weeks after treatment if asymptomatic, while it is advised to defer chlamydia TOC until 6 weeks after treatment initiation. Chlamydia TOC is recommended only during pregnancy or if there is clinical suspicion of ongoing or re-infection, although there have been recent concerns about the efficacy of single dose azithromycin therapy. Many patients are co-infected with gonorrhoea and chlamydia, and with dual-platform NAATs it is simple and cost-effective to obtain chlamydia and gonorrhoea results from the same sample.

Aim To identify whether it is feasible to perform chlamydia and gonorrhoea NAAT TOCs simultaneously within 42 days of treatment in dual-infected patients.

Methods 38 patients with chlamydia who had repeat NAAT tests within 42 days of initiation of treatment were identified using clinical coding and pathology results. Demographic details, treatment type and time elapsed from initiation of treatment to TOC were obtained from patient notes.

Results 36/38 (94.7%) of chlamydia TOCs taken 41 days or less since the initiation of treatment were negative, including 8/8 (100%) of tests taken 14 days or less since chlamydia treatment. One positive test was from a male, the other from a female, 21 and 17 days after treatment respectively. Both were treated with azithromycin. The male patient denied sexual contact since treatment, and it was unclear whether the female patient was at risk of re-infection.

Conclusions 95% of patients in a clinical setting tested negative for chlamydia within 42 days of treatment. Performing a NAAT TOC for chlamydia and gonorrhoea simultaneously in dual-infected patients is therefore feasible, and is a cost-effective and convenient way to reassure patients that both infections have been eradicated. More work is needed to establish the cause of ongoing chlamydia positivity within 42 days of treatment.