LGV is caused by serotypes L1, L2, and L3 of the bacteria Chlamydia trachomatis. These serotypes differ from the chlamydial serotypes that cause trachoma, inclusion conjunctivitis, and chlamydial urethritis and cervicitis because they can invade and reproduce in regional lymph nodes.
LGV occurs sporadically in the US but is endemic in parts of Africa, India, Southeast Asia, South America, and the Caribbean. It is diagnosed much more often in men than women. LGV is being increasingly reported in North America, Europe, and Australia among men who have sex with men (MSM).
Lymphogranuloma venereum occurs in 3 stages.
The 1st stage begins after an incubation period of about 3 days with a small skin lesion at the site of entry. It may cause the overlying skin to break down (ulcerate) but heals so quickly that it may pass unnoticed.
The 2nd stage usually begins in men after about 2 to 4 weeks, with the inguinal lymph nodes on one or both sides enlarging and forming large, tender, sometimes fluctuant masses (buboes). The buboes stick to deeper tissues and cause the overlying skin to become inflamed, sometimes with fever and malaise. In women, backache or pelvic pain is common; the initial lesions may be on the cervix or upper vagina, resulting in enlargement and inflammation of deeper perirectal and pelvic lymph nodes. Multiple draining sinus tracts may develop and discharge pus or blood.
In the 3rd stage, lesions heal with scarring, but sinus tracts can persist or recur. Persistent inflammation due to untreated infection obstructs the lymphatic vessels, causing swelling and skin sores.
People who engage in receptive anal sex may have severe proctitis or proctocolitis with bloody purulent rectal discharge during the 1st stage. In the chronic stages, colitis simulating Crohn disease may cause tenesmus and strictures in the rectum or pain due to inflamed pelvic lymph nodes. Proctoscopy may detect diffuse inflammation, polyps, and masses or mucopurulent exudate—findings that resemble inflammatory bowel disease.
Lymphogranuloma venereum is suspected in patients who have genital ulcers, swollen inguinal lymph nodes, or proctitis and who live in, have visited, or have sexual contact with people from areas where infection is common. LGV is also suspected in patients with buboes, which may be mistaken for abscesses caused by other bacteria.
Diagnosis has usually been made by detecting antibodies to chlamydial endotoxin (complement fixation titers > 1:64 or microimmunofluorescence titers > 1:256) or by genotyping using a polymerase chain reaction-based NAAT. Antibody levels are usually elevated at presentation or shortly thereafter and remain elevated.
Direct tests for chlamydial antigens with immunoassays (eg, enzyme-linked immunosorbent assay [ELISA]) or with immunofluorescence using monoclonal antibodies to stain pus or NAATs may be available through reference laboratories (eg, Centers for Disease Control and Prevention in the US).
All sex partners should be evaluated.
After apparently successful treatment, patients should be followed for 6 months.
Doxycycline 100 mg orally twice a day, erythromycin 500 mg orally four times a day, or tetracycline 500 mg orally four times a day, each for 21 days, are effective for early disease. Azithromycin 1 g orally once a week for 1 to 3 weeks is probably effective, but neither it nor clarithromycin has been adequately evaluated.
Swelling of damaged tissues in later stages may not resolve despite elimination of the bacteria. Buboes may be drained by needle or surgically if necessary for symptomatic relief, but most patients respond quickly to antibiotics. Buboes and sinus tracts may require surgery, but rectal strictures can usually be dilated.
If people have sexual contact with a person who has lymphogranuloma venereum during the 60 days before the person's symptoms began, they should be examined and tested for urethral, cervical, or rectal chlamydial infection depending on the site of exposure. They should be treated presumptively (with a single dose of azithromycin 1 g orally or doxycycline 100 mg orally twice a day for 7 days) regardless of whether evidence suggests that they have LGV.