Ectoparasites and endoparasites in sexually transmitted diseases.

A number of protozoan organisms, both ectoparasitic and endoparasitic, may be related to sexual activity. The broad range of clinical presentations makes this group of diseases challenging to diagnose. Patients may present with skin, genital, gastroenterologic, pulmonary, or neurologic symptoms, or may be asymptomatic. A careful history, including specific sexual history, with appropriate laboratory evaluation will aid the primary care physician in making the correct diagnosis and thus supply the correct treatment. Awareness that infection with multiple organisms is frequent in some populations is important. Prevention of reinfection or further transmission of the disease must be aggressively pursued by patient education about the means of transmission of the disease and avoidance of high-risk sexual practices.