Lymphogranuloma venereum (LGV), also known as lymphogranuloma inguinale, tropical bubo, Nicholas-Favre disease, and sixth venereal disease, is an infection caused by a variety of the bacterium Chlamydia trachomatis. It primarily causes painful swelling of the lymph nodes located closest to the site of infection. If left untreated, it can cause serious tissue damage, scarring, rectal or intestinal blockages, and extreme swelling of the genitals (elephantiasis). In severe cases, it attacks the central nervous system.
Incidence and Prevalence of Lymphogranuloma
LGV is relatively rare in the United States and most industrialized countries, where it infects an average of 250 to 400 people a year, mostly men, between the ages of 15 and 24. Prevalence is highest in Southeast Asia, Africa, Central and South America, and the Caribbean, hence "tropical bubo."
Causes of Lymphogranuloma
LGV is spread by direct sexual contact with the genitals, rectum, or mouth. Once in the body, bacteria reproduce in the lymph nodes. It may be most closely associated with anal sex and men who have sex with men. Newborns can contract the disease from infected mothers during birth.
Signs and Symptoms of Lymphogranuloma
Sores resembling pimples or blisters may appear where the bacteria entered the body, but not always. They often heal quickly, without leaving a scar. Discharge from the penis or vagina is a common early stage symptom. These signs usually appear within 3 days to 1 month after exposure.
Second-stage symptoms are more pronounced and generally begin 1 to 2 weeks after early-stage symptoms appear. The lymph nodes located closest to the site of infection, usually in the groin, swell and form a painful, pus-filled swelling (bubo). Buboes can grow as large as a lemon, and the skin over them may turn blue. They are usually accompanied by throbbing pain, fever, malaise, or headache. In about 30% of cases, the bubo breaks through the skin, drains continuously, remains open, and becomes infected by other bacteria. A burst bubo can take months to heal completely and often leaves a scar.
Buboes may form near the throat, neck, anus, rectum, and cervix. Involvement of the rectum and anus can cause rectal discharge and cause the lining of the rectum to swell, bleed, and erode. If erosion spreads to the colon, the rectum may swell almost closed. Women may experience backache if buboes form on the cervix or in the upper vagina. Chronic inflammation of the lymph nodes can lead to genital elephantiasis, narrowing of the rectal passage (stricture), perirectal abscess, and abnormal rectal channels or tunnel-like lesions (fistulas).
Physicians typically diagnose LGV by visual observation and blood tests that identify bacteria and antibodies produced by the body to fight the infection. Blood tests also rule out or identify other STDs, such as herpes, syphilis, chancroid, and gonorrhea. A sample of the discharge may be taken to be cultured.
Treatment for Lymphogranuloma
A 3-week course of antibiotics, usually tetracycline, doxycycline, or erythromycin, is prescribed to kill bacteria. Buboes may remain after infection is cured and are usually surgically drained with a needle. Surgical repair of fistulas and erosion may be necessary. In cases of elephantiasis, plastic surgery may be helpful. Physicians routinely observe patients for about 6 months after treatment.