Infective keratitis

1. INFECTIVE KERATITIS
PROF. DR. ANUPAMA MANOHARAN
2nd year Dip. In Ophthal
GOVT. STANLEY MEDICAL COLLEGE HOSPITAL

2. CORNEAL ULCER
 A discontinuation in the normal epithelial surface of the
cornea + necrosis of the surrounding corneal tissue
 Edema & cellular infiltration

4. ETIOLOGICAL CLASSIFICATION OF
INFECTIVE KERATITIS
 Bacterial
 Viral
 Fungal
 Chlamydial
 Protozoal
 Spirochetal

5. BACTERIAL CORNEAL ULCER

9. ORGANISMS CAUSING
BACTERIAL CORNEAL
ULCER
 Staphylococcus aureus Pneumococcus(ulcus
serpens)
 Pseudomonas pyocynaea Staphylococci
 Streptococcus pneumoniae Streptococci
 E.coli Gonococci
 Proteus Moraxella
 Klebsiella Pseudomonas pyocyanea
 N.gonorrhoea
 N.meningitidis
 C.diphtheria
ORGANISMS CAUSING
HYPOPYON CORNEAL
ULCER

10. STAGES OF BACTERIAL CORNEAL
ULCER

11. 1) STAGE OF PROGRESSIVE
INFILTRATION
 Infiltration of lymphocytes into the epithelium from peripheral
circulation & stroma.
 Necrosis of tissue occurs.

12. 2) STAGE OF ACTIVE ULCERATION
 Results from necrosis & sloughing of the epithelium,
Bowman’s membrane & stroma.
 Exudation into the anterior chamber from vessels of iris &
ciliary body lead to hypopyon formation
 Ulcer may further progress as follows :
(i) by lateral extension resulting diffuse
superficial ulceration.
(ii) by deeper penetration leading to
descemetocele & corneal peforation.

13. 3) STAGE OF REGRESSION
 Induced by natural host defence mechanisms.
 Accompanied by vascularisation that increases the immune
response.
 The ulcer now begins to heal & epithelium begins to grow
over the edges.

14. 4) STAGE OF CICATRIZATION
 Healing continues by progressive epithelialization.
 Beneath the epithelium , fibrous tissue is laid down by
fibroblasts & endothelium of the new vessels.
 The degree of scarring varies :
Superficial ulcer involving only epithelium heals
without scar.
Ulcer involving Bowman’s membrane Nebula
Ulcer involving half of stroma Macula
Ulcer involving more than half of stroma Leucoma

15. CORNEAL OPACITY GRADES
develops as
Healed Corneal Ulcers corneal opacity
 NEBULA : Faint opacity due to superficial scars involving
Bowman’s layer & superficial stroma.
 MACULA : Semi dense opacity. Scarring involves half the
corneal stroma.
 LEUCOMA : Dense white opacity. Scarring more than half of
stroma

16. CORNEAL OPACITY

17. A.NEBULAR B.MACULAR C.LEUCOMA D.ADHERENT LEUCOMA

19. BACTERIAL CORNEAL ULCER WITH
HYPOPYON

20. COMPLICATIONS OF CORNEAL
ULCER
 Toxic Iridocyclitis due to absorption of toxins in the
chamber.
 Secondary glaucoma due to fibrinous exudates blocking
the anterior chamber.
 Descematocele due to effect of IOP the Descemet’s
membrane herniates. A sign of impending perforation.
 Perforation of corneal ulcer sudden strain due to cough,
sneeze or spasm of orbicularis muscle. Following
perforation pain reduces and hot fluid (Aqueous) comes out
of eyes.

21. DESCEMETOCELE

22. INVESTIGATIONS
 Routine – hemogram , blood sugar
 Specific – corneal scrapping
gram stain
culture & antibiotic sensitivity
Ocular examination – Regurgitation test & syringing

23. TREATMENT
Treatment of uncomplicated corneal ulcer
1) Specific treatment
2) Non specific treatment
3) Physical & general measures

24. TREATMENT
1. SPECIFIC TREATMENT
Topical antibiotics
 Fortified cefazoline 50 mg/ml and
 Fortified tobramycin 13.6 mg/ml
 Alternative – fortified vancomycin 50 mg/ml
Systemic antibiotics
 Cephalosporin
 Aminoglycoside
 Oral ciproflox

25. TREATMENT
2. NON SPECIFIC TREATMENT
 Cycloplegic drugs – atropine
 Systemic analgesics & anti-inflammatory –
paracetamol/brufen
 Vitamins – A,B,C
3. GENERAL MEASURES
 Hot fomentation
 Dark goggles
 Rest, good diet

26. CAUSES OF NON HEALING CORNEAL
ULCER
 Local causes
IOP, concretions, misdirected cilia, impacted foreign
body, dacrocystitis, lagophthalmos, excessive corneal
vascularization.
 Systemic causes
DM
severe anemia
malnutrition
patients on systemic steroids

27. TREATMENT OF NON HEALING ULCER
 Removal of known causes
 Mechanical debridement of ulcer
 Cauterisation of ulcer
 Bandage of soft contact lens
 Peritomy

28. TREATMENT OF IMPENDING
PERFORATION

29. TREATMENT OF PERFORATED CORNEAL
ULCER

31. FUNGAL CORNEAL ULCER

32. MYCOTIC CORNEAL ULCER
Etiology :-- Filamentous -
1. Causative Fungi
Yeast -
2. Modes of infection
Aspergillus, Fusarium
,Alternaria,
Cephalosporium,
Curvularia , Penicillium
Candida ,
Cryptococcus
Injury by vegetative
material
Injury by animal tail
Secondary fungal ulcers

36. FUNGAL CORNEAL ULCER WITH
SATELLITE LESIONS , RING INFILTRATE
& HYPOPYON

37. IMMUNE RING

38. FUNGAL CORNEAL ULCER IN CONTACT
LENS WEARERS

39. IMMOBILE HYPOPYON

40. CLINICAL PICTURE
BACTERIAL CORNEAL ULCER VIRAL CORNEAL ULCER
Symptoms more marked
 Pain & FB sensation
 Watering
 Photophobia
 Blurred vision
 Redness of eyes
Signs
 Wet looking, yellowish
green
 Swelling of lids
 Blepharospam
 Conjunctival hyperemia
 Mobile hypopyon
Symptoms less marked
Signs more marked
 Dry looking, greyish white ,
rolled out margins
 Feathery finger like
extensions
 Sterile immune ring
 Satellite lesions
 Immobile hypopyon

41. INVESTIGATIONS
STAINING
KOH mount Periodic Acid Schiff
Calcofluor white Methenamine silver

42. KOH MOUNT – ASPERGILLUS
Aspergillus fumigatus Aspergillus flavus Aspergillus
niger

43. CULTURE
 Corneal scrapes should be plated
on Sabouraud dextrose agar.
 Most fungi also grow on
blood agar or in enrichment media.
 Sensitivity testing for antifungal agents.
 Contact lenses and cases should be sent for culture.

44. NEWER METHODS
 Immunoflourescence staining
 electron microscopy
 PCR
 Confocal microscopy frequently permits identification of
organisms in vivo.

45. TREATMENT
 Hospitalization
 Discontinuation of contact lens wear
 Empirical treatment initiated before microscopy results
 Cycloplegics- to reduce pain, prevents posterior synechiae
 Control blood sugar levels
 broad spectrum antibiotic
 Treat lacrimal apparatus

46. TREATMENT
TOPICAL ANTIFUNGAL DRUGS.
Initial drug of choice – 5% natamycin hrly – for 2 weeks
 Amhotericin B 0.15% with or without fluconazole 2%
 voriconazole 1%
 Nystatin eye ointment
 SYSTEMIC ANTIFUNGALS –
 Tablet fluconazole or ketoconazole
 Intracameral fluconazole
.

47. SURGICAL TREATMENT
Perforation – actual or impending:
• Tissue adhesives- cyanoacrylate glue –
small perforations <3mm
• Conjunctival flap- patch graft –
large perforations 5mm
• Therapeutic keratoplasty (penetrating or deep anterior
lamellar)
Superficial keratectomy can be effective to de-bulk a
lesion