Schistosomiasis: Genital manifestations

Schistosoma haematobium is the main species causing genital manifestations but other species of schistosomiasis have been implicated.

The number of people suffering from genital manifestations is not precisely known. The biological plausibility of a causal association between genital schistosomiasis and HIV has been described, and may be an important factor in increasing the risk of contracting HIV in areas or communities where both infections are coendemic.

The clinical manifestations of genital schistosomiasis occur both in women and in men.

In men, the symptoms include epididymitis (an inflammation of the eipdidymis at the back of the testicle) which can simulate tuberculosis and associated funiculitis, indolence and possible fistulization, hemospermia, pain during urination prostatitis and others.

In women, the symptomatology is unspecific because urogenital schistosomiasis can provoke gynaecological ailments. The most frequently observed signs and symptoms are abdominal and pelvic pain presenting in forms such as dyspareunia, dysmenorrhea, leucorrhoea, menstrual disorders, post-coital bleeding or simple contact bleeding (during an examination), cervicitis, endometritis and salpingitis. The disease evolves most often in a chronic manner. These genital lesions can cause complications such as early abortion, ectopic pregnancy and infertility.

The clinical appearance of genital lesions is variable.

Genital schistosomiasis may be associated with the presence of schistosome eggs (ova) in the genitals in both men and women. However, ova are not always concurrently present, and current laboratory methods have a low sensitivity to confirm their presence. Lesions associated with genital schistosomiasis may mimic a host of infections and premalignant or malignant conditions. It is therefore crucial to identify alterations that are pathognomic. Differential diagnosis must be done systematically to screen for cancers (of the vulva, vagina, cervix, endometrium), sexually transmitted infections and urogenital tuberculosis.

Clinical diagnosis of female genital schistosomiasis is mainly done by visual inspection and histological methods.

The WHO Female Genital Schistosomiasis Pocket Atlas and related Clinical Poster are visual aides that have been developed for clinical health-care professionals to raise the clinical index of suspicion and facilitate identification of these lesions, especially in low-resource settings.

Treatment with praziquantel kills the adult worms and provides relief and regression of inflammatory lesions. Few studies reported that praziquantel has no effect on established grainy lesions. However, elimination of adult worms prevents further egg deposition in the tissues and thus development of new lesions. Early treatment, especially in childhood, is the most effective intervention to prevent the occurrence and development of complications associated with urogenital schistosomiasis.

The widespread lack of awareness of genital schistosomiasis leads to misdiagnosis and, therefore, false and ineffective therapy . As female genital schistosomiasis is rarely diagnosed correctly, knowledge about the effect of treatment is also scanty. Incorrect diagnostic of genital schistosomiasis lesions frequently leads to debilitating and irreversible operations such as ovarectomy, salpingotomiy and hysterectomy. It is therefore of utmost importance to sensitize health workers and raise awareness of urogenital schistosomiasis, particularly in endemic countries.

Regular treatment with praziquantel from an early age prevents schistosomiasis from progressing to genital damage and other related complications. In endemic areas, WHO recommends regular large-scale administration of preventive chemotherapy to entire communities or routinely in health facilities.

The public health advantages of anthelminthic treatment with praziquantel go beyond the simple benefits of curing schistosomiasis and preventing its related genital morbidity. Regardless of the presumptive causal association with HIV infection, urogenital schistosomiasis is a disabling disease by itself, and it should be prevented with the currently available means. The WHO recommended policy of regularly treating school-age children with praziquantel should be reinforced and extended, to involve collaborations with programmes for preventing HIV and other sexually transmitted infections.