chlamydial conjunctivitis............pptx

1. CHLAMYDIAL Conjunctivitis

2. Infiltration Scarring

3. CHLAMYDIA Family: Chlamydiaceae Genus: Chlamydia, Chlamydophila C. trachomatis Urogenital infections, Trachoma, Conjunctivitis, Pneumonia, Lymphogranuloma venerium (LGV) C. psittaci Pneumonia (Psittacosis) C. pneumoniae Bronchitis, sinusitis, Pneumonia

4. Small obligate intracellular parasites Contains DNA, RNA and ribosomes Gram Negative cell wall Cell wall not well characterized Inner and outer membrane LPS but no peptidoglycan Dependant on energy molecules Can’t make ATP MICROBIOLOGY Left- Cluster of spore-like, C. trachomatis elementary bodies located intracellularly, inside one of the larger epithelial cells. Right- Under a magnification of 200X, Chlamydia trachomatis bacteria, and intracellular C. trachomatis inclusion bodies.

5. Two morphological forms Elementary body Reticulate body Elementary bodies (EB) Small (0.3 - 0.4 µm), Extracellular Rigid outer membrane, Resistant Non-replicating, non-metabolically active Infectious Bind to columnar epithelial cells / Macrophages PHYSIOLOGY AND STRUCTURE

6. Reticulate bodies (RB) Larger (0.8 - 1 µm) Intracellular Fragile membrane Metabolically active Replicating Non-infectious EB RB ↓ ↓ ←

7. DEVELOPMENTAL CYCLE OF CHLAMYDIA EB bind to host cells Epithelial cell Macrophage Internalization Endocytosis Phagocytosis Inhibition of phagosome-lysosome fusion Reorganization into RB Growth of RB by binary fission Reorganization into EB Inclusion bodies Release of EB Lysis - C.psittaci Extrusion - C.trachoma and C.pneumoniae

8. PATHOGENESIS AND IMMUNITY (C.TRACHOMATIS) Infects epithelial cells / Macrophages Down regulation of Class I MHC Infiltration of PMNs and lymphocytes Lymphoid follicle formation Fibrosis Disease results from destruction of cells and host immune response No long lasting immunity; reinfection results in inflammatory response

9. CHLAMYDIA TRACHOMATIS Adult Inclusion conjunctivitis Trachoma Pneumonia in infants Urogenital infections Reiter’s Syndrome Lymphogranuloma venerium (LGV)

10. ADULT INCLUSION CONJUNCTIVITIS Oculogenital infection usually caused by serovars (serological variants) D–K of C. trachomatis Affects 5–20% of sexually active young adults in Western countries. Transmission is by autoinoculation from genital secretions. The incubation period is approximately a week.

11. DIAGNOSIS Symptoms: Subacute onset of unilateral or bilateral redness, watering and discharge. Untreated, becomes chronic and though self-limiting may persist for several months. Signs: Watery or mucopurulent discharge. Tender preauricular lymphadenopathy . Large follicles prominent in the inferior fornix and also in the upper tarsal conjunctiva. Superficial punctate keratitis . Perilimbal subepithelial corneal infiltrates may appear after 2–3 weeks. Chronic cases have less prominent follicles and commonly develop papillae. Mild conjunctival scarring and superior corneal pannus .

12. Adult chlamydial conjunctivitis. (A) Large forniceal follicles; (B) superior tarsal follicles; (C) peripheral corneal infiltrates; (D) superior pannus

13. TREATMENT Start with Empirical treatment. Referral to a genitourinary specialist is mandatory in confirmed cases. Systemic therapy involves one of the following: Azithromycin 1 g repeated after 1 week is the treatment of choice. Some guidelines advocate only a single 1 g dose. Doxycycline 100 mg twice daily for 10 days ( tetracyclines are relatively contraindicated in pregnancy/breastfeeding and in children under 12 years of age). Erythromycin, amoxicillin and ciprofloxacin are alternatives.

14. TREATMENT ….. CONT’D Topical antibiotics such as erythromycin or tetracycline ointment used to achieve rapid relief of ocular symptoms, but are insufficient alone. Reduction of transmission risk involves abstinence from sexual contact until completion of treatment (1 week after azithromycin ). Re-testing for persistent infection to be done 6–12 weeks after treatment. Symptoms take weeks to settle and follicles and corneal infiltrates can take months to resolve due to a prolonged hypersensitivity response to chlamydial antigen.

15. TRACHOMA PATHOGENESIS World’s leading cause of preventable irreversible blindness Related to poverty, overcrowding and poor hygiene The morbidity is the result of the establishment of re-infection cycles within communities Whereas an isolated episode of trachomatous conjunctivitis may be relatively innocuous Recurrent infection elicits a chronic immune response consisting of a cell-mediated delayed hypersensitivity (Type IV) reaction to the intermittent presence of chlamydial antigen and can lead to loss of sight

16. Prior contact with the organism confers short-term partial immunity but also leads to a heightened inflammatory reaction upon re-infection Vaccination is not helpful . The fly is an important vector, but there may be direct transmission from eye or nasal discharge Associated principally with infection by serovars A, B, Ba and C of Chlamydia trachomatis Serovars D–K conventionally associated with adult inclusion conjunctivitis and other species of the Chlamydiaceae family such as Chlamydophila psittaci and Chlamydophila pneumoniae have also been implicated.

17. Diagnosis Features are divided into an ‘active’ inflammatory stage and a ‘cicatricial’ chronic stage, with considerable overlap WHO Grading of Trachoma Tf = Trachomatous Inflammation (Follicular): five or more follicles (>0.5 mm) on the superior tarsal plate TI = trachomatous inflammation (intense): diffuse involvement of the tarsal conjunctiva, obscuring 50% or more of the normal deep tarsal vessels; papillae are present TS = trachomatous conjunctival scarring: easily visible fibrous white tarsal bands TT = trachomatous trichiasis : at least one lash touching the globe CO = corneal opacity sufficient to blur details of at least part of the pupillary margin

18. MACALLAN CLASSIFICATION Stage 1: Superior tarsal follicles, mild superior SPK, and pannus , often preceded by purulent discharge and tender preauricular node. Stage 2: Florid superior tarsal follicular reaction (2a) or papillary hypertrophy (2b) associated with superior corneal SEIs, pannus , and limbal follicles. Stage 3: Follicles and scarring of superior tarsal conjunctiva. Stage 4: No follicles, extensive conjunctival scarring . Late complications : Severe dry eyes, trichiasis , entropion , keratitis , corneal scarring, superficial fibrovascular pannus , Herbert pits (scarred limbal follicles), corneal bacterial superinfection , and ulceration.

19. Trachoma. (A) Typical white subtarsal follicles; (B) marked pannus; (C) stellate conjunctival scarring (arrow); (D) Arlt line and conjunctival follicles; (E) Herbert pit (arrow); (F) cicatricial entropion

20. Active trachoma is most common in pre-school children and is characterized by the following: Mixed follicular/papillary conjunctivitis associated with a mucopurulent discharge Superior epithelial keratitis and pannus formation Cicatricial trachoma is prevalent in middle age . Linear or stellate conjunctival scars in mild cases, or broad confluent scars ( Arlt line ) in severe disease. Although the entire conjunctiva is involved, the effects are most prominent on the upper tarsal plate. Superior limbal follicles may resolve to leave a row of shallow depressions (Herbert pits). Trichiasis , distichiasis , corneal vascularization and cicatricial entropion Severe corneal opacification . Dry eye caused by destruction of goblet cells and the ductules of the lacrimal gland.

21. The SAFE strategy supported by the WHO encompasses Surgery for trichiasis , Antibiotics for active disease, Facial hygiene and Environmental improvement. Antibiotics should be administered to those affected and to all family members. A single antibiotic course is not always effective in eliminating infection in an individual and communities may need to receive annual treatment to suppress infection. A single dose of azithromycin (20 mg/kg up to 1 g) is the treatment of choice. Erythromycin 500 mg twice daily for 14 days or doxycycline 100 mg twice daily for 10 days ( tetracyclines are relatively contraindicated in pregnancy/breastfeeding and in children under 12). Topical 1% tetracycline ointment is less effective than oral treatment. Management

22. Facial cleanliness is a critical preventative measure. Environmental improvement, such as access to adequate water and sanitation, as well as control of flies, is important. Surgery is aimed at relieving entropion and trichiasis and maintaining complete lid closure, principally with bilamellar tarsal rotation.