Chlamydia Trachomatis (pp 364)

This species has been subdivided into three biovars: trachoma, LGV (L1,L2,L3  lymphogranuloma venereum) & mouse pneumonitis. Receptors to EB (Chl. Trachomatis) retricted to nonciliated columnar, cuboidal, or transitional epithelial cells. These are found in the respiratory tract, conjunctiva, fallopian tubes, urethra, endometrium etc. The biovars have been further subdivided into 15 serovars.

The diseases caused are widespread, depending on the serovars involved.

1. Occular disease:

   • Trachoma is a chronic disease caused by serovars A, B, C. Conjunctive becomes inflamed, conjunctiva becomes scarred, patient’s eyelids turn inward and then ulcerate the cornea, eventually leading to loss of vision.

   • Adult Inclusion Conjunctivitis (D-K serovars): associated with genital infections in sexually active adults. Corneal scarring results. Neonatal inclusion conjunctivitis (D-K serovars): purulent discharge from eye is characteristic.
     

2. Genito-urinary disease (Serovars D-K)

   • Females are usually asymptomatic, whereas males are usually symptomatic (this is generally the case for most genital infections in both sexes). Females can end up with: cervicitis, endometritis, urethratitis, salpingitis, PID, infertility etc. There is a mucopurulent discharge evident.

3. Pulmonary Disease (Serovars S-K)

   • Occasionally cause interstitial (infant pneumonia) in infants. Onset generally 2-3 weeks after birth

4. Pharyngitis (Serovars D – K)

5. Lymphogranuloma venereum (LGV, L1-L3):

   • Incubation period of 1-4 wks, primary lesion occurs at glans, penis, urethra, vagina, cervix, scrotum etc. Often painless papule , and small. Can experience fever, headache etc at time of lesion. 2^nd inflammation of lymph nodes around area of infection, usually inguinal nodes – may burst and become fistulas (often painful, enlargement). May progress to chronic ulcerative phase causing genital elephantiasis.

Category: Microbiology Notes