This is a presentation regarding Fungal (Mycotic) and Viral Keratitis

1. MYCOTIC & VIRAL KERATITIS
SUGIN GLEN BAISIL J
MBBS-PREFINAL YEAR
KANYAKUMARI GOVT. MEDICAL
COLLEGE
AASARIPALLAM

2. FUNGAL KERATITIS
• Major cause of visual loss on Tropical &
Developing countries
CAUSATIVE ORGANISMS
Mainly 2 types
1. Yeasts (eg. Candida)
Common in Temperate climates
2. Filamentous fungi (eg. Fusarium &
Aspergillus)
Common in Tropical climates

3. PREDISPOSING FACTORS
i. Chronic occular surface diseases
ii. Long term use of Topical steroids
iii. Contact lens wear
iv. Systemic immunosuppression
v. Diabetes

4. Candida & Filamentous Keratitis
CLINICAL FEATURES:
Symptoms:
• Gradual onset of pain
• Grittiness
• Photophobia
• Blurred vision
• Watery/ Mucopurulent discharge

5. Signs:
a) Candida keratitis:
▪ Yellow white densely suppurative
infiltrate
▪ Collar stud morphology
b) Filamentous Keratitis:
▪ Grey/Yellow white stromal infiltrate
▪ Progressive infiltration with satellite
lesion
▪ Feathery branch like extension as a ring
shaped infiltrate
▪ Rapid progression with thinning & necrosis
▪ Penetration of intact Descemet’s membrane
may occur and lead to endophthalmitis

6. Candida keratitis
▫ yellow white dense infiltrate is
seen

7. Filamentous keratitis
▫ feathery branch like
extension

8. Other Features:
▪ Epithelial defect
▪ Anterior Uveitis
▪ Hypopyon
▪ Endothelial plaque
▪ Raised IOP
▪ Scleritis
▪ Sterile or Infective endophthalmitis
Differential diagnosis:
□ Bacterial Keratitis
□ Herpetic keratitis
□ Acanthamoebal keratitis

9. Investigation:
I. Staining:
a) Gram & Giemsa staining (50% sensitive)
b) Periodic acid schiff(PAS)
Grocott- Gomori Methenamine Silver(GMS)
II. Culture:
In Sabouraud’s dextrose agar
(Corneal scrapes, contact lenses & cases, etc.)
III. Corneal biopsy:
Indication- Absence of clinical improvement for 3-4
days (or) no growth in culture for 1 week
2-3 mm block→ culture & histopathological
analysis
IV. Confocal microscopy
V. PCR

10. Treatment:
Improvement may be slow compared to bacterial
infection
1. General measures
Hospital admission-usually
2. Removal of epithelium
(to enhance penetration of antifungal drugs)
3. Topical treatment(48 hours)
For Candida
Amphotericin B (0.1-0.3%) or Econazole 1%
Alt: Natamycin 5%, Fluconazole 2%, Clotrimazole 1%
For Filamentous
Natamycin 5% or Econazole 1%
Alt: Amphotericin B 0.15%, Miconazole 1%

11. ▪Broad spectrum Antibiotics- to prevent bacterial
contamination
▪Cycloplegics- for bacterial keratitis
4. Subconjunctival fluconazole- in severe cases
5. Systemic antifungals (2-3 weeks)
Voriconazole- 400mg bd for 1 day
shift- 200mg bd daily
Itraconazole- 200mg daily
shift- 100mg daily
Fluconazole- 200mg BD
6. Tetracyclins (Doxycycline-100mg BD)
→Anticollagenase effect in case of thinning
7. Superficial keratectomy
8. Therapautic penetrating keratoplasty

12. VIRAL KERATITIS
Commonly includes
1) Herpes simplex keratitis
2) Herpes zoster ophthalmicus
3) Adenovirus keratitis

13. Herpes Simplex keratitis
Most common cause for blindness in
developing countries
HSV-I → by kissing or close contact
HSV-II→ to neonates through infected
genitalia of mother

14. Primary Herpes
1) Skin lesions
2) Conjunctiva
▪ Acute follicular
Conjunctivitis
3) Cornea
▪ Fine epithelial punctate
keratitis
▪ Coarse epithelial punctate
keratitis
▪ Dendritic ulcer
Recurrent Herpes
1) Active epithelial keratitis
▪ Punctate epithelial keratitis
▪ Dendritic ulcer
▪ Geographical ulcer
2) Stromal keratitis
▪ Disciform keratitis
▪ Diffuse stromal necrotic
keratitis
3) Trophic keratitis(meta-
herpetic)
4) Herpetic iridocyclitis

15. Primary Ocular herpes
Incidence:
Occur in a nonimmune person
Children of 6 months to 5 years of age and
in teenagers
Clinical Features:
1) Systemic: Fever, Malaise & non-
suppurative lymphadenopathy
2) Skin lesions: Vesicular lesions
3) Occular lesions:
▪ Acute follicular conjuctivitis
▪ Keratitis

16. Recurrent Ocular Herpes
Involvement of trigeminal nerve
Predisposing factors:
▪ Fever
▪ Exposure to UV rays
▪ General ill health
▪ Emotional or physical exhaustion
▪ Mild trauma
▪ Menstrual stress following steroids and
immunosuppressive drugs administration

17. Herpes simplex keratitis

18. Epithelial keratitis
(dendritic/geographical)
Symptoms
• Redness
• Mild discomfort
• Photophobia
• Watering
• Blurred vision

19. Signs
1. Swollen opaque epithelial cells arranged
in coarse or punctate or stellate pattern.
2. Central desquamation results in linear
branching ulcer mostly at the centre.
3. Ends of the ulcer have characteristic
terminal buds and bed of ulcer skin with
fluorescein.
4. The virus laden cells at the margin of the
ulcer stain with rose bengal.
5. Corneal sensation is reduced.
6. ↑ IOP.
7. Mild subepithelial scarring may develop.

20. Differential diagnosis:
• Herpes zoaster keratitis
• Healing corneal abrasion
• Acanthamoeba keratitis
• Epithelial rejection in a corneal graft

21. Treatment:
1) Topical antiviral drugs
▪ Aciclovir 3% ointment. 5 times a day for
14-21 days
▪ Ganciclovir (0.15% gel) 5 times a day
until the ulcer heals and then 3 times a day
for 5 days
▪ Trifluorothymidine 1% drops 2 hourly
until ulcer heals and then 3 times a day for
5 days
▪ Adenine arabinose(Vidarabine)
3% ointment 5 times a day until ulcer heals
and then 3 times a day for 5 days.

22. 2) Mechanical debridement
Corneal surface is wiped with a sterile
cellulose sponge 2 mm beyond the edge
of ulcer
Antivirals must be used in conjunctiva
3) Systemic antiviral drugs
▪ Acyclovir 400 mg p.o. tid to bid, or
▪ Famcyclovir 250 mg p.o. bid, or
▪ Valacyclovir 500 mg p.o. bid
for a period of 10-21 days
4) Interferon monotherapy
Nucleoside antivirals +
Interferon/debridement

23. Disciform Keratitis
Clinical features:
Symptoms:
▪ Gradual onset of blurred vision
▪ Halos around light
▪ Discomfort
▪ Redness
Signs:
1. Central zone of stromal edema
2. Keratic precipitates underlying
3. Folds in descemet’s membrane
4. Wessley’s immune ring
5. ↑IOP & ↓corneal sensation

24. Disciform keratitis

25. Treatment:
▫ Diluted steroid eye drops 4-5 times a day
with antivirals(acyclovir 3%) twice a day
▫ Non specific & supportive treatment

26. Necrotizing stromal keratitis
Active viral replication within the stroma
Signs:
1. Stromal necrosis & melting; profound
interstitial opacification
2. Anterior uveitis with keratic precipitates
3. Epithelial defect
4. Progression to scarring, vascularisation
and lipid deposits
Treatment
▫ Systemic antiviral drugs for 10-21 days
▫ Keratoplasty

27. Metaherpetic keratitis
▪ Occurs at the site of previous herpetic
ulcers
▪ Persistant defect in BM of corneal
epithelium
Clinical features
1. Indolent linear or ovoid epithelial defect
2. Margin- grey/thickened
Treatment
▫ Artificial tears
▫ Bandage soft contact lens
▫ Lid closure(tarsorhaphy)

28. Herpes Zoster Ophthalmicus
Causative: Varicella zoster virus
Risk of ocular involvement
▫ Hutchinson’s sign
▫ Age: 6th and 7th decades
▫ AIDS - predominant

30. General features:
1. Prodromal phase 3-5 days
tiredness, fever, malaise, headache
2. Skin lesions
▫ Midline rashes
▫ Erythematous areas with maculopapular
rashes
3. Boggy edema of upper & lower eyelids
4. Vesicle → pustule; dry, crest
5. Large deep hemorrhagic lesion

32. Treatment:
Systemic therapy:
1. Acyclovir 800mg 5 times daily for 10 days
2. Strong oral analgesics for treating pain
during first 2 weeks
3. Systemic steroids for progressive
proptosis with 3rd nerve palsy & optic
neuritis
4. NSAIDs like oxyphenbutazone in severe
scleritis

33. Topical agents:
▪ Antiviral and antibiotic ointments
▪ In case of Herpetic infection,
Dexamethasone 0.1% drops 4 hourly +
antiviral ointment 5 times a day + steroid
ointment at night
▪ In case of dryness, artificial tears are
required