Background
Lymphogranuloma venereum (LGV) is a sexually transmitted infection (STI) that primarily infects the lymphatics. [1]
In 1833 the disease was first explained by Wallace, but at the time thought to be a "tropical bulbo"; however, in 1912 Rost discovered the disease was venereal in origin. [2]
LGV synonyms include lymphopathia venerea, tropical bubo, climatic bubo, strumous bubo, poradenitis inguinales, Durand-Nicolas-Favre disease, and lymphogranuloma inguinale.
Pathophysiology
LGV is caused by serovars L1, L2, L2b, and L3 of Chlamydia trachomatis. [3] It gains entrance into the body through skin breaks and abrasions, or it crosses the epithelial cells of mucous membranes. The organism travels via the connective tissue into the lymphatic system to multiply within mononuclear phagocytes in regional lymph nodes.
Transmission is predominantly sexual. However, transmission by fomites, nonsexual personal contact, and laboratory accidents have been documented. The creation of aerosols of this organism has been associated with infection and pulmonary symptoms.
LGV can be asymptomatic or present as progressive symptoms in 3 stages. [3]
Primary stage
The primary stage presents as a small, painless papule that can ulcerate to form a herpetiform lesion or chancre. Mucopurulent discharge of the rectum, urethra, or cervix may occur during this stage depending on the initial site of pathogen inoculation.
Secondary stage
The secondary stage is classically described as the inguinal stage, which starts approximately 2-6 weeks after the primary lesion presents. The inguinal stage is defined by painful inguino-femoral lymphadenopathy, referred to as "buboes". This is the hallmark sign of the disease.
Receptive anal sex can result in rectal incoculation that causes proctitis and infection of the perirectal and pelvic lymph nodes. Due to the location of these lymph nodes pelvic, lower abdominal, or low back pain may occur. In women, these nodes may also become involved as a result of lymphatic spread from the cervix and posterior vaginal wall.
Early in the course of the disease, the nodes appear fleshy and show diffuse reticulosis.
Later, suppurative granulomatous lymphadenitis and perilymphadenitis occur with matting of the nodes. Frequently, these nodes coalesce to form stellate abscesses.
Histologically, these abscesses are nearly diagnostic, but the clinical appearance may be similar to those seen in other infections, including cat scratch fever and mycobacterial granulomatous infections.
Tertiary stage
If left untreated, LGV can progress to the tertiary stage several years after the initial infection. In this stage, an anogenitorectal syndrome may occur with resultant rectal stricture or elephantiasis of the genitalia.
This syndrome is found predominantly in women and homosexual men, because of the location of the involved lymphatics.
During the tertiary stage, proctitis can advance to proctocolitis, which is caused by hyperplasia of intestinal and perirectal lymphatic tissue.
This inflammation forms perirectal abscesses, ischiorectal abscesses, rectovaginal fistulas, anal fistulas, and rectal stricture. In very late stages, fibrosis and granulomas is likely to occur.
Chlamydial organisms are scarce at this stage.
Extragenital inoculation sites
Extragenital inoculation sites can produce regional lymphadenopathy. Examples are of mediastinal lymphadenopathy from inhalation of C trachomatis, or submandibular and cervical chain lymphadenopathy following inoculation after oral sex. [4]
Epidemiology
Frequency
United States
Sporadic cases occur in North America, Australia, and most of Asia. Most cases in the United States involve recent travel to an endemic area where the patient was sexually active; therefore, obtaining a travel history is important. Historically, the average number of LGV cases in the United States has been fewer than 600 per year. However, in 2015-2016 there was an outbreak of 38 confirmed, probable and suspected cases among men who have sex with men and were co-infected with HIV in Michigan. [5] However, within the United States there is likely under-detection of LGV due to the lack of widespread testing for chlaymdia trachomatis serovars.
International
LGV is endemic in East and West Africa, India, Southeast Asia, South America, the Caribbean, and Australia. [6] In 2003, an outbreak of LGV among men who have sex with men occurred in the Netherlands. [7] Since 2003, the L2 and L2b serovars of LGV have been endemic among men who have sex with men in western Europe and Australia, [8, 9, 10, 11] with the United Kingdom having the largest documented outbreak. [7]
Mortality/Morbidity
If treated appropriately and during stage I or II, patients usually have complete resolution of symptoms.
Death can occur from tertiary LGV if complete bowel obstruction from rectal stricture leads to perforation, however this is rare.
Sex
LGV is diagnosed in men up to 6 times more frequently than in women.
Age
LGV infection is most common in the second and third decades when sexual activity is highest.
