Chlamydia trachomatis types LGV 1, 2 and 3 are responsible for this sexually transmitted infection. It is endemic in the tropics, with the highest incidences in Africa, India and South East Asia.

Clinical features

The primary lesion is a painless ulcerating papule on the genitalia occurring 7-21 days following exposure. It is frequently unnoticed. A few days to weeks after this heals, regional lymphadenopathy develops. The lymph nodes are painful and fixed and the overlying skin develops a dusky erythematous appearance. Finally, nodes may become fluctuant (buboes) and can rupture. Acute LGV also presents as proctitis with perirectal abscesses, the appearances sometimes resembling anorectal Crohn’s disease. The destruction of local lymph nodes can lead to lymphoedema of the genitalia.

Diagnosis

The diagnosis is often made on the basis of the characteristic clinical picture after other causes of genital ulceration or inguinal lymphadenopathy have been excluded. Syphilis and genital herpes must be excluded.

• Isolation of C. trachomatis in tissue culture. The sensitivity is 75-85%.
• Antigen-detection methods with material from bubo aspirates or ulcer scrapes:
• direct immunofluorescence using monoclonal antibodies
• enzyme immunoassay (EIA).
• Sensitivity 70-80%.
• Positive C. trachomatis serology (complement fixation tests, L-type immunofluorescence or micro-immunofluorescence test, IF). A fourfold rise in antibody titre in the course of the illness is diagnostic. NB: Micro-IF is the only serological means of distinguishing different serotypes of CT.

Treatment

Early treatment is critical to prevent the chronic phase. Doxycycline (100 mg twice daily for 21 days) or erythromycin (500 mg four times daily for 21 days) is efficacious. Follow-up should continue until signs and symptoms have resolved, usually 3-6 weeks. Chronic infection may result in extensive scarring and abscess and sinus formation. Surgical drainage or reconstructive surgery is sometimes required. Sexual partners in the 30 days prior to onset should be examined and treated if necessary.

Genital infection with CT is common, with up to 5% of sexually active women in the UK infected. It is regularly found in association with other pathogens: 20% of men and 40% of women with gonorrhoea have been found to have coexisting chlamydial infections. In men 40% of non-gonococcal and post-gonococcal urethritis is due to Chlamydia. As CT is often asymptomatic much infection goes unrecognized and untreated, which sustains the infectious pool in the population. The long-term complications associated with Chlamydia infection, especially infertility, impose significant morbidity in the UK. The organism has a world-wide distribution.

Clinical features

In men CT gives rise to an anterior urethritis with dysuria and discharge; infection is asymptomatic in up to 50% and detected by contact tracing. Ascending infection leads to epididymitis. Rectal infection leading to proctitis occurs in men practising anoreceptive intercourse. In women the most common site of infection is the endocervix where it may go unnoticed; up to 80% of infection in women is asymptomatic. Symptoms include vaginal discharge, post-coital or intermenstrual bleeding and lower abdominal pain. Ascending infection causes acute salpingitis. Reiter’s disease (see p. 568) has been related to infection with C. trachomatis. Neonatal infection, acquired from the birth canal, can result in mucopurulent conjunctivitis and pneumonia.

Diagnosis

CT is an obligate intracellular bacterium, which complicates diagnosis. Cell culture techniques provide the ‘gold standard’ but are expensive and require considerable expertise. Indirect diagnostic tests include direct fluorescent antibody (DIF) tests, enzyme immunoassays (EIA) and nucleic acid amplification techniques such as PCR or ligase chain reaction (LCR): none is diagnostic.
In men first-voided urine samples are tested, or urethral swabs obtained. In women endocervical swabs are the best specimens, and up to 20% additional positives will be detected if urethral swabs are also taken. Urine specimens are much less reliable than endocervical swabs in women and are not recommended. Specimen quality is critical and it must contain cellular material.

Treatment

Tetracyclines or macrolide antibiotics are most commonly used to treat Chlamydia. Doxycycline 100 mg 12-hourly for 7 days or azithromycin 1 g as a single dose are both effective for uncomplicated infection. Tetracyclines are contraindicated in pregnancy. Other effective regimens include erythromycin 500 mg four times daily. Routine test of cure is not necessary after treatment with doxycycline or azithromycin, although if symptoms persist or reinfection is suspected then further tests should be taken. Sexual contacts must be traced and treated, particularly as so many infections are clinically silent.

The medical and psychological management of people who have been sexually assaulted requires particular sensitivity and should be undertaken by an experienced clinician in ways that reduce the risks of further trauma. Post-traumatic stress disorder is common. Although most frequently reported by women, both women and men may suffer sexual assault. Investigations for and treatment of sexually transmitted infections in people who have been raped can be carried out in GUM departments. Collection of material for use as evidence, however, should be carried out within 7 days of the assault by a physician trained in forensic medicine and must take place before any other medical examinations are performed.

History

In addition to the general medical, gynaecological and contraceptive history, full details of the assault, including the exact sites of penetration, ejaculation by the assailant and condom use should be obtained, together with details of the sexual history both before and after the event.

Examination

Any injuries requiring immediate attention must be dealt with prior to any other examination or investigations. Accurate documentation of any trauma is necessary. Forced oral penetration may result in small palatal haemorrhages. In cases of forced anal penetration, anal examination including proctoscopy should be carried out, noting any trauma.

Investigations

A full STI screen at presentation with a second examination 2 weeks later is recommended. Cultures for Neisseria gonorrhoeae and tests for Chlamydia trachomatis should be obtained from all sites of actual or attempted penetration. C. trachomatis culture is the only test currently accepted as evidence. Gram-stained slides of urethral, cervical and rectal specimens for microscopy for gonococci should be performed. Bacterial vaginosis, yeasts and Trichomonas vaginalis (TV) tests should be carried out on vaginal material. Syphilis serology should be requested and a serum saved. Hepatitis B, HIV and hepatitis C testing should be offered. Specimens should be identified as having potential medicolegal implications.

Management

Preventative therapy for gonorrhoea and chlamydia may be advised using a single dose combination of ciprofloxacin 500 mg and azithromycin 1 g. Hep B vaccine should be offered and may be of value up to 3 weeks after the event. HIV prophylaxis may be offered within 72 hours of the assault, based upon a specific risk assessment. Post-coital oral contraception may be given within 72 hours of assault. Psychological care provision and appropriate referral to support agencies should be arranged. Sexual partners should be screened and treated if necessary.

Initial follow-up at 2 weeks should be arranged to review the patient’s needs and the prophylaxis regimens that are in place, with further follow-up as needed.

Although the history and examination will guide investigation, it must be remembered that multiple infections may coexist, some being asymptomatic. Full screening is indicated in any patient who may have been in contact with an STI.

In men:

• Urethral smears for Gram staining
• Urethral swabs for gonococcal culture and Chlamydia testing
• Two-glass urine test and urinalysis
• Rectal swabs for Gram staining and culture for N. gonorrhoeae and C. trachomatis
• Throat swab for culture for N. gonorrhoeae
• Blood for syphilis and HIV serology (with counselling).

In women:

• Smears from the lateral vaginal wall for Gram staining
• Vaginal swab for culture of Candida and Trichomonas
• A wet preparation is made from the posterior fornix for Trichomonas and for the potassium hydroxide test for bacterial vaginosis
• The pH of vaginal secretions using narrow-range indicator paper
• Endocervical smears and swabs for Gram staining, gonococcal culture and Chlamydia tests
• Urethral smears and swabs for Gram staining and gonococcal culture
• Rectal and throat swabs for N. gonorrhoeae and C. trachomatis, if indicated
• Urinalysis
• Cervical cytology
• Blood for syphilis and HIV serology (with counselling).

Additional investigations when indicated:

• Urine sample for nucleic acid amplification tests if available locally
• Blood for hepatitis B and C serology
• Swabs for HSV and Haemophilus ducreyi from clinically suspicious lesions into special media
• Smears and swabs from the subpreputial area in men with balanoposthitis (inflammation of glans penis and prepuce) for candidiasis
• Scrapings from lesions suspicious of early syphilis for immediate dark-ground microscopy
• Pregnancy testing
• Cervical cytology
• Stools for Giardia, Shigella or Salmonella from those practising oral/anal sex.