fungalkeratitis.pptx of fungal corneal infection

Fungal involvement of cornea management and treatment

1. Fungal Keratitis Dr Gudiya Rana JR1 Ophthalmology

2. INTRODUCTION Fungal keratitis is potentially blinding infection of cornea. Considered one of the major cause of ocular morbidity in developing countries. Most common in tropical & sub-tropical countries.

3. Etiology Non-filamentous (yeast) : Candida filamentous with septae : Aspergillus spp Fusarium spp Cladosporium spp Curvularia

4. Risk factors Chronic ocular surface disease Long term use of Topical Steroid Immunosuppression Diabetes Agricultural Trauma Contact Lens Wear

5. PATHOPHYSIOLOGY Adherence Penetration Host response. Defect in corneal epithelium Fungi enter into the corneal stroma Multiplication of fungi Release of toxins, proteolytic enzymes, fungal antigen Release of lysosomal substances by PMNs Destruction of corneal stroma

6. Clinical features Symptoms- symptoms are lesser as compared to sign Gradual onset of pain Photophobia Grittiness Blurred vision Watery/ mucopurulent discharge

7. Signs filamentous keratitis Grey/ yellow-white stromal infiltrate with indistinct fluffy margins Progressive infiltration with satellite lesions Feathery branch like extension Ring- shaped infiltrate (immune ring of wessely ) Rapid progression with necrosis & thinning can occur Penetration of intact descemets membrane may occur & lead to endophthalmitis without evident perforation. OTHERS: hypopyon, endothelial plaque, raised IOP, scleritis, sterile or infective endophthalmitis

8. CANDIDA KERATITIS Yellow white densely suppurative infiltrate is typical

9. INVESTIGATIONS Sample for laboratory investigations should be acquired before starting antifungal therapy. STAINING: KOH preparation with direct microscopic evaluation- rapid diagnostic tool, highly sensitive Gram & Giemsa staining- 50% sensitive, Others- PAS, calcofluor white, methenamine silver.

10. Continued… 2. CULTURE: Corneal scrapings should be sent for culture in all suspected cases It is important to obtain an effective scrape from the ulcer base, Media should include: Sabouraud dextrose agar. Blood agar Enrichment media. If cultures are negative but have high clinical suspicion, consider corneal biopsy

11. Saboraud agar chocolate agar blood agar

12. 3. PCR Rapid & highly sensitive up to 90% & may be the current IOC. Expensive. 4. CORNEAL BIOPSY Indication suspected fungal keratitis in the absence of clinical improvement after 3-4 days. No growth develops from scraping after a week Filamentous fungi- proliferates just anterior to Descemet's membrane, so deep stromal specimen may be required. Continued…

13. Continued.. 5 ) ANTERIOR CHAMBER TAP : Done in resistant cases with endothelial exudate because organism may penetrate the endothelium.

14. Treatment (Medical management ) Topical antifungal agents ( mainstay of treatment ) Natamycin 5% (FDA-approved) Amphotericin B 0.15% Voriconazole 1or 2 % Econazole 1% Clotrimazole 1%

15. Combination oral 1.VORICONAZOLE 400 mg twice daily X 1 day Then 200 mg twice daily 2.ITRACONAZOLE 200 mg once daily Reduced to 100 mg once daily (or FLUCOAZOLE 200 mg twice daily ) Indications : Severe deep keratitis Scleritis Endophthalmitits

16. Adjunctive treatment Broad -spectrum Antibiotics Cycloplegic agent Systemic analgesic and anti-inflammatory- to relieve pain and decrease edema. Multivitamins to improve immunity and help in healing Systemic ascorbic acid to accelerate corneal remodeling and healing Antiglaucoma medication

17. Signs of improvement Decreased pain Decreased size of infiltrate. Disappeared satellite lesions Rounding of feathery margins

18. Duration of antifungal treatment 4-6 weeks on average. If no improvement in 1 week ? Check lab results Change medications If the Infection continues to worsen? Consider Surgical interventions

19. Treatment ( Surgical management ) Epithelial debridement.

20. Treatment ( Surgical management ) Anterior chamber wash with Intracameral injection voriconazole / amphotericin B (50  µ g/0.1 mL) Intrastromal therapy voriconazole and amphotericin B Intravitreal amphotericin B, fluconazole and voriconazole Subconjuctival therapy  miconazole (10 mg in 0.5 mL) and fluconazole (0.5–1.0 mL of a 2% solution);

21. Treatment ( Surgical management ) Conjunctival flap – They provide vascularized tissue to the infected area to supply humoral and cellular immunity while providing serum growth factors to enhance healing . They also act as a biological bandage reducing pain and stromal necrosis . Penetrating or lamellar keratoplasty (PKP) or (LK) is the definitive management.

22. DIFFERENTIAL DIAGNOSIS Bacterial keratitis Acanthamoeba   keratitis Herpes simplex virus (HSV)) keratitis