The Etiologic Diagnosis of Corneal Ulcers at a Tertiary Eye Center in

Kathmandu, Nepal.

Michael R. Feilmeier, MD

Geoffrey C. Tabin, MD

Kavitha R. Sivaraman, BA

Matthew Oliva, MD

Reeta Gurung, MD

The authors have no financial interest in the material presented in this electronic poster.

PurposeTo determine the etiologic diagnosis of

infectious corneal ulcers at Tilganga Institute of Ophthalmology (TIO), a tertiary referral and teaching hospital in Kathmandu, Nepal

Materials and Methods Study Design: Retrospective Consecutive Case Series

AnalysisCorneal scrapings were obtained from all patients with

suspected infectious keratitis presenting to TIO from August 2006-July 2009.

Material from scrapings was innoculated directly on to blood, chocolate, and Saboraud dextrose agars as well as brain-heart infusion broth.

A portion of each sample was examined with Gram stain and KOH prep.

Antibiotic cultures were examined at 24-hour intervals and considered negative if there was no growth at 96 hours.

Fungal cultures were incubated at 27 C for four weeks.Bacterial were identified based on morphological, staining,

and biochemical properties and fungi based on colony characteristics and microscopic appearance.

Results: Demographics (n=440)

Results:Corneal Scaping Results at TIO:

Smear Microscopy in Culture + Cases

Results: Culture Positive Organism Distribution

468 Patients

283 (60%) Culture Negative 185 (40%) Culture Positive

113 (61%) Fungi 72 (39%) Bacteria

40 (35%) Asperigillus spp

14 (12%) Fusarium spp

14 (12%) Candida spp

65 (90%) Gram Positive

7 (10%) Gram Negative

50 (69%) S. pneumo

8 (11%) S. aureus

5 (7%) S. epidermidis

1 (1%) S. pyogenes

1 (1%) S. viridans

4 (6%) Pseudomonas

2 (3%) Proteus

1 (1%) Acinetobacter

25 (22%) Fungus, not specified

7 (6%) Tricophyton spp.

3 (3%) Curvalaria spp

10 (9%) Cladosporium

Results: Comparison to the Literature

Results:

Antibiotic Sensitivity Testing: Percentage of Isolates Sensitive

Results:Antibiotic Sensitivity Testing:

Percentage of Isolates Not Resistant (At least partially sensitive)

ConclusionIn this population, fungi are the most common cause of

infectious keratitis.

Aspergillus sp. is the most common fungus implicated in this setting

S. pneumoniae was the most common single pathogen identified.

No seasonal variation in infectious etiology was noted in this study

Vancomycin resistant organisms were identified in this study, which is in support of previous microbiologic studies in this region of the world.

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