We used an in-house molecular assay for the detection of Klebsiella granulomatis in ulcer specimens collected over a 12-year surveillance period in order to determine whether a diagnosis of donovanosis could be ascribed to genital ulcer disease (GUD) of unknown aetiology in our setting.
Between 2007 and 2018, a total of 974 genital ulcer specimens with no previously identified sexually transmitted (STI) pathogens were selected from STI aetiological surveys conducted in all nine provinces of South Africa. Giemsa-stained ulcer smears from the same participants had previously been routinely analysed for the presence of typical Donovan bodies within large mononuclear cells. A Klebsiella screening assay targeting the phoE (phosphate porin) gene was used in combination with restriction digest analysis and sequencing to confirm the presence of K. granulomatis.
The Klebsiella screening assay tested positive in 19/974 (2.0%) genital ulcer specimens. Restriction digest analysis and nucleotide sequencing of the phoE gene confirmed that none of these specimens was positive for K. granulomatis DNA. Similarly, Donovan bodies were not identified in the Giemsa stained ulcer smears of these specimens.
This is the first study to assess K. granulomatis as a cause of genital ulceration in South Africa over a 12-year surveillance period using molecular methods. The results demonstrate that K. granulomatis is no longer a prevalent cause of GUD in our population.