C. trachomatis causes a variety of diseases. It is an importantcause of genital and ocular infections worldwide. C. trachoma-tis LGV biovar causes lymphogranuloma venereum (LGV) andocular LGV. C. trachomatis trachoma biovar causes (a) trachoma, (b) adult inclusion conjunctivitis, (c) neonatal conjunctivitis, (d) infant pneumonia, and (e) urogenital infections.
C. trachomatis LGV biovar (serotypes L1, L2, L2a, L2b, andL3) causes lymphogranuloma venereum. Serotype L2 is most commonly responsible for the condition. LGV is a sexually transmitted disease that affects the cervix, urethra, salpin-ges, and epididymis. Incubation period varies from 1 to 4 weeks.
Fever, headache, and myalgia are the other associated symp-toms. Inflammation and swelling of the lymph nodes draining the primary site of infection is the next stage of the disease. The regional lymph nodes, such as inguinal lymph nodes in males and intrapelvic and pararectal lymph nodes in females, are most commonly involved. These lymph nodes become painful, enlarged, fluctuant, and finally may rupture with the forma-tion of draining fistulas. Such lymph nodes are called buboes. Fever, chills, anorexia, headache, and myalgia are the other associated manifestations.
Proctitis is a common manifestation in women with LGV (Color Photo 52). This occurs due to lymphatic spread of the bacteria from the infected cervix or the vagina. Proctitis also occurs in men, resulting from lymphatic spread from the urethra or following anal intercourse. In untreated cases of LGV, the infection may progress to a chronic ulcerative stage leading to development of ulcers, strictures, fistula, or genital elephantiasis. In some other cases, the infection may resolve at this stage.
C. trachomatis LGV biovar also causes ocular LGV. This causesParinaud’s oculogenital conjunctivitis. It is a condition char-acterized by inflammation of the conjunctiva associated with periauricular, submandibular, and cervical lymphadenopathy.
Trachoma is a communicable disease of the eye caused by C. trachomatis serotypes A, B, Ba, and C. This is a conditioncharacterized by follicular hypertrophy, papillary hyperplasia, pannus formation, and in late stages cicatrization. The condi-tion begins in patients with follicular conjunctivitis with diffuse inflammation that affects entire conjunctiva. Subsequently, the condition progresses with the formation of pannus, which indicates invasion of blood vessels of cornea and finally loss of vision. The loss of vision is the most important and serious complication of trachoma.
Adult inclusion conjunctivitis results from the infection with C. trachomatis strains associated with genital infection (A, B, Ba,and D–K). This infection is more frequently seen in sexually active adults. The condition can also occur in neonates. A uni-ocular and less commonly binocular red eye, ocular discharge, marked hyperemia, papillary hypertrophy, and a predominant follicular conjunctivitis are the important manifestations. The condition if untreated progresses to a chronic remittent course, keratitis, and possible iritis.
This is the neonatal form of inclusion conjunctivitis. The con-dition develops in infants acquiring the infection from infected birth canal. The infection is usually seen in infants born to pregnant mothers who have chlamydial infections of the cervix.
Incubation period varies from 5 to 12 days. Swelling of the infant’s eyelid, hyperemia, and purulent discharge characterize the condition. Conjunctival scarring and corneal vasculariza-tion occurs in untreated infections of long duration.
Infant pneumonia caused by C. trachomatis is seen in infants between 4 and 16 weeks of age. It is one of the most common causes of pneumonia in the newborns. This infection is seen in 60% of neonates born to infected mothers.
The incubation period is variable but usually takes 2–3 weeks after birth. The condition is characterized by respiratory symp-toms, such as rhinitis with cough and wheezing. Child is usually afebrile during the disease.
Urogenital infection is the most common infection caused by C. trachomatis. Approximately, 80% of infected females and 50%of infected males are asymptomatic. Genital chlamydiasis is the most common sexually transmitted disease worldwide.
The clinical manifestations in symptomatic patients include urethritis (nongonococcal urethritis), epididymitis, proctitis, and conjunctivitis in males; in females, it causes a mucopuru-lent cervicitis, endometritis, and salpingitis.
Ascending infection can result in pelvic inflammatory disease, chronic pelvic pain, and perinephritis. Chlamydial infection with C. trachomatis; especially serotype C is shown to be at a risk of developing cervical cancer, nearly 6.5 times more than in women without infection.