The changing epidemiology of genital ulcer disease in South Africa: has donovanosis been eliminated?

OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Detección de infecciones de transmisión sexual por técnicas de biología molecular / Detection of sexually transmitted infections using molecular biology techniques

Las infecciones de transmisión sexual precisan para su control de pruebas diagnósticas rápidas, fiables y que permitan su realización en situaciones de cribado. Las técnicas de biología molecular han supuesto una verdadera revolución diagnóstica. Debido a su elevada sensibilidad, no solo detectan más infecciones, sino que permiten la obtención de muestras poco invasivas que facilitan los programas de cribado y evitan el rechazo de los pacientes a la realización de toma de muestras. La mejora de su especificidad evita en muchos casos la realización de pruebas de confirmación, bajo la premisa del cumplimiento de normas de calidad. También permiten diagnosticar patógenos que las técnicas de cultivo son incapaces de recuperar, y cada vez tenemos plataformas diagnósticas más sencillas, versátiles y en formato múltiple que agilizan el trabajo en el laboratorio e incluso fuera de él (AU)

Sexually transmitted infections (STI) require rapid, reliable diagnostic tests that can be performed in screening situations. Molecular biology techniques have been a true diagnostic revolution. Due to their high sensitivity, they detect more infections and allow non-invasive sample collection, simplifying screening programs and minimising patient refusal to have samples taken. Improvements in specificity have reduced the need for confirmation tests in many cases, under the premise of compliance with quality standards. They also allow to identify pathogens that culture techniques are unable to recover. Moreover, diagnostic platforms are increasingly simple, versatile and available in multiplex format, facilitating work inside and outside the laboratory (AU)

Chancroid, lymphogranuloma venereum, granuloma inguinale, genital herpes simplex infection, and molluscum contagiosum.

Chancroid, lymphogranuloma venereum, and granuloma inguinale may be considered as tropical venereal diseases. These diseases were a major diagnostic and therapeutic challenge in past centuries. Currently, patients with these bacterial infections that are endemic to the tropics occasionally consult with dermatologists in temperate climates. Due to the increasing frequency of travel to the tropics for tourism and work, as well as the increasing number of immigrants from these areas, it is important for dermatologists practicing in temperate climates to be familiar with the dermatologic manifestations of such infections, to be prepared to diagnose these diseases, and to treat these patients. All three "tropical" infections respond well to prompt and appropriate antimicrobial treatment, although herpes progenitalis still cannot be cured, and the number of people infected keeps growing; moreover, genital herpes can be transmitted by viral shedding before and after the visual signs or symptoms. Acyclovir, valacyclovir, and famciclovir can shorten outbreaks and make them less severe or even stop them from happening. There is currently no etiologic treatment for molluscum contagiosum, and the majority of treatment options are mechanical, causing a certain degree of discomfort. The molluscum contagiosum virus, unlike the other infectious agents mentioned, does not invade the skin.

Squamous cell carcinoma complicating donovanosis not a thing of the past!

Donovanosis causes granulomatous ulceration of genitalia and neighbouring sites with little tendency to heal spontaneously. It is uncommonly seen nowadays in sexually transmitted infection clinics of north India. The present case is reported for its scarcity and to make clinicians aware of this disease which may rarely accompany carcinoma.

Cutaneous metastases of rectal mucinous adenocarcinoma mimicking granuloma inguinale.

A 46-year-old man complained of ulcerovegetative lesions in the anogenital region, which he had noted one month prior to presentation. The patient had a history of travel to African countries. Therefore, the ulcerovegetative lesions of the patient were suspected to be granuloma inguinale (GI). Calymmatobacterium granulomatis was not observed in the direct examination of scrapings collected from the base of the ulcerovegetative lesion. Instead, a histological examination revealed cutaneous metastasis of mucinous adenocarcinoma of the rectum. Therefore, a diagnosis of GI was eliminated. As the patient did not report his history of rectal cancer and had travelled to African countries, we had primarily focused on the diagnosis of GI.

[Utility of molecular biology techniques in the diagnosis of sexually transmitted diseases and genital infections]. / Utilidad de las técnicas de biología molecular en el diagnóstico de las infecciones de transmisión sexual y otras infecciones genitales.

Historically, the diagnosis of sexually transmitted diseases (STDs) has been difficult. The introduction of molecular biology techniques in microbiological diagnosis and their application to non-invasive samples has produced significant advances in the diagnosis of these diseases. Overall, detection of Neisseria gonorrhoeae by molecular biology techniques provides a presumptive diagnosis and requires confirmation by culture in areas with a low prevalence. For Chlamydia trachomatis infections, these techniques are considered to be the most sensitive and specific procedures for mass screening studies, as well as for the diagnosis of symptomatic patients. Diagnosis of Mycoplasma genitalium infection by culture is very slow and consequently molecular techniques are the only procedures that can provide relevant diagnostic information. For Treponema pallidum, molecular techniques can provide direct benefits in the diagnosis of infection. Molecular techniques are not established for the routine diagnosis of donovanosis, but can be recommended when performed by experts. Molecular methods are advisable in Haemophilus ducreyi, because of the difficulties of culture and its low sensitivity. In genital herpes, molecular techniques have begun to be recommended for routine diagnosis and could soon become the technique of choice. For other genital infections, bacterial vaginosis, vulvovaginal candidosis and trichomoniasis, diagnosis by molecular methods is poorly established. With genital warts, techniques available for screening and genotyping of endocervical samples could be used for certain populations, but are not validated for this purpose.

Donovanosis: an update.

Donovanosis has been ignored for many years until recently. The condition still has a limited geographical distribution. A significant epidemic of donovanosis has been identified in KwaZulu/Natal, South Africa where it may be a risk factor for acquiring HIV in men. After a gap of more than 30 years, the organism was cultured by researchers in Durban, South Africa and Darwin, Australia. Polymerase chain reaction (PCR) techniques for donovanosis were developed soon after, most recently using a colorimetric detection system. Similarities between the causative organism, Calymmatobacterium granulomatis and Klebsiella spp. were confirmed. A proposal that the organism be reclassified under the genus Klebsiella has been put forward. Azithromycin has been confirmed as the drug of choice but is yet to be accepted universally because of cost issues. Treatment in patients with significant HIV induced immune deficiency may need to be prolonged. A donovanosis eradication programme is underway amongst the aboriginal community in Australia. Elsewhere, management through current syndromic guidelines for genital ulcers are yet to be validated in areas where donovanosis is endemic. PCR testing should enable further recognition of donovanosis and lead to more concerted efforts in disease control and possible eradication.

Phylogenetic evidence for reclassification of Calymmatobacterium granulomatis as Klebsiella granulomatis comb. nov.

By sequencing a total of 2089 bp of the 16S rRNA and phoE genes it was demonstrated that Calymmatobacterium granulomatis (the causative organism of donovanosis) shows a high level of identity with Klebsiella species pathogenic to humans (Klebsiella pneumoniae, Klebsiella rhinoscleromatis). It is proposed that C. granulomatis should be reclassified as Klebsiella granulomatis comb. nov. An emended description of the genus Klebsiella is given.

Phylogenetic analysis of Calymmatobacterium granulomatis based on 16S rRNA gene sequences.

Calymmatobacterium granulomatis is the aetiological agent of granuloma inguinale - a chronic granulomatous genital infection - and is morphologically similar to members of the genus Klebsiella. This study determined the 16S rRNA gene sequence of C. granulomatis and the taxonomic position of the organism in relation to the genus Klebsiella. Genomic DNA was extracted from C. granulomatis-infected monocytes and from frozen and formalin-fixed paraffin wax-embedded tissue biopsy specimens from patients with histologically proven granuloma inguinale. The 16S rDNA was amplified by PCR with broad range oligonucleotide primers. The amplified DNA fragments were cloned into pMOS vector, digested with Bam HI and Pst1 restriction endonucleases, hybridised with a gram-negative bacterial probe (DL04), sequenced in both directions by the automated ALF DNA sequencer, verified on an ABI Prism 377 automated sequencer and analysed with DNASIS and MEGA software packages. Sequence analysis revealed DNA homology of 99% in C. granulomatis from the different sources, supporting the belief that the bacteria in the culture and the biopsy specimens belonged to the same species, although there was some diversity within the species. Phylogenetically, the strains were closely related to the genera Klebsiella and Enterobacter with similarities of 95% and 94% respectively. C. granulomatis is a unique species, distinct from other related organisms belonging to the gamma subclass of Proteobacteria.

Ultrastructure of Calymmatobacterium granulomatis: comparison of culture with tissue biopsy specimens.

The ultrastructural features of cells of Calymmatobacterium granulomatis from monocyte co-cultures and tissue biopsy specimens were compared. In cultures the bacteria were mainly extracellular, i.e., not within membrane-bound vacuoles. The bacterial body was surrounded by a uniformly extensive homogeneous layer with a relatively high electron density. This layer varied considerably in tissue biopsy specimens, having either homogeneously electron-dense or delicate web-like structures with varying density and thickness. In tissue specimens the bacteria were located predominantly within vacuoles of varying sizes in the cytoplasm of the macrophages and, occasionally, extracellularly within the intercellular spaces of the stroma. The bacterial cytoplasm contained ribosomes scattered throughout with electron-dense granules located peripherally. The trilaminar cell-wall structure was typical of a gram-negative organism, comprising an outer membrane, a middle electron-opaque layer and an inner plasma membrane. Surface structures such as fimbriae, flagella and bacteriophages were not identified in specimens from either source.

Culture of the causative organism of donovanosis (Calymmatobacterium granulomatis) in HEp-2 cells.

We report successful culture of Calymmatobacterium granulomatis by standard cell culture methods. Swabs were obtained from lesions in three patients with a clinical diagnosis of donovanosis. For two patients, there was histological confirmation of the disease (i.e., the presence of Donovan bodies in Giemsa-stained smears). Specimens were inoculated onto cycloheximide-treated HEp-2 cell monolayers in RPMI 1640 medium (supplemented with fetal calf serum, NaHCO3, vancomycin hydrochloride, and benzylpenicillin). At 48 h, organisms resembling Donovan bodies were identified in monolayer cultures from all three specimens. The organisms appeared as pleomorphic bacilli with characteristic bipolar staining and "safety pin" appearance. Using a PCR designed to differentiate C. granulomatis from the Klebsiella species (which have a high degree of molecular homology), we were able to demonstrate that the cultured organisms produced a PCR product identical to that obtained from the original swab specimens. It is now possible to test in vitro susceptibility of C. granulomatis to antibiotics and to provide a ready source of DNA and antigenic material to enable the development of serological tests and, possibly in the future, a vaccine.

Growth and cultural characteristics of Calymmatobacterium granulomatis--the aetiological agent of granuloma inguinale (Donovanosis).

Granuloma inguinale is a chronic destructive granulomatous disease of the genitalia. The clinical diagnosis is often unreliable and the definitive diagnosis is based on the visualisation of 'Donovan bodies' in tissue smears or biopsy specimens. The organism implicated in its aetiology, Calymmatobacterium granulomatis, was reported to have been cultured > 30 years ago, but little is known about the organism because of its fastidious nature and the difficulty in culturing it. Twenty-two biopsy specimens from female patients with clinical and laboratory-confirmed granuloma inguinale were treated with amikacin 10 mg/L and inoculated in a monocyte co-culture system with peripheral blood mononuclear cells (PBMC) from a single donor and autologous sera. The method was subsequently modified by pretreatment of specimens with vancomycin 5 mg/L and metronidazole 10 mg/L in addition to amikacin 10 mg/L for the purpose of decontamination, pooled blood donor PBMC and by the use of heat-inactivated fetal calf serum instead of autologous serum for culture. This modified method was used to culture additional biopsy specimens and genital ulcer scrapings from female and male patients, respectively. All monocyte co-cultures were examined by a rapid Giemsa (RapiDiff) stain and by an indirect immunofluorescence test with immune sera. Representative cultures were examined by transmission electron microscopy. C. granulomatis was successfully isolated in pure culture by the monocyte co-culture system from four biopsy specimens and 14 genital ulcer scrapings. The cultured organisms were visible both intra- and extra-cellularly and were extremely pleomorphic, with characteristic single and biopolar condensation. The numbers of the organisms increased after each passage. All positive cultures showed bright fluorescence when tested with immune sera. Transmission electron microscopy of the cultured bacteria demonstrated a typical gram-negative cell wall consisting of an outer membrane, middle electron opaque layer and an inner plasma membrane. The capsule was thick and electron dense. Numerous electron dense granules were present within the cytoplasm.

Laboratory techniques used in the diagnosis of chancroid, granuloma inguinale, and lymphogranuloma venereum.

The preceding discussion summarized the historical, modern, and evolving laboratory techniques for the diagnosis of chancroid, GI, and LGV. The correct diagnosis of these sexually transmitted diseases, which are uncommon in the United States and Europe but often endemic in Africa, Asia, and South American, can usually be made if appropriately selected laboratory techniques are used to confirm the presumptive clinical impression.