title: Comparison of clinical and microbiological profiles in smear-positive and smear-negative cases of suspected microbial keratitis.
abstract: OBJECTIVE
  To examine the hypothesis that initial smear examination results have a significant bearing on the management and outcome of suspected microbial keratitis.
  
  
  METHODS
  One hundred and seventy consecutive patients with suspected microbial keratitis were included in a prospective nonrandomized comparative study and their detailed clinical and microbiological data (smears and cultures of corneal scrapings) were captured on a predesigned corneal ulcer database. Patients were divided into two groups: Group 1 included 68 patients with corneal scrapings negative in smears while Group 2 included 102 patients with corneal scrapings positive in smears. The two groups were compared for their clinico-microbiological profile, management and clinical outcome. The outcome was noted at three months. Fisher's exact test was applied for statistical analysis.
  
  
  RESULTS
  Cultures were sterile in 57.3% of patients in Group 1 compared to 17.6% in Group 2. Scrapings that grew S. pneumoniae, gram-negative organisms, fungi and Acanthamoeba were more often positive in smears (18.6%, 11.8%, 19.6% and 2.9% respectively). While data on duration of prior treatment was not available, prior medication made no significant difference to smear results. More (79.3%) patients of Group 1 had small infiltrate size (
  
  
  CONCLUSIONS
  Initial smear examination helps in instituting specific therapy thereby improving the outcome in cases of microbial keratitis. Positive smears indicate greater severity of disease and prior medication may not be a significant cause of smear negativity.
authors.affiliation: Jhaveri Microbiology Centre, Hyderabad Eye Research Foundation, L.V. Prasad Eye Institute, Hyderabad, India. savitri@lvpei.org
authors.forename: Savitri
authors.initials: S
authors.lastname: Sharma
authors.forename: Mukesh
authors.initials: M
authors.lastname: Taneja
authors.forename: Rakesh
authors.initials: R
authors.lastname: Gupta
authors.forename: Anjali
authors.initials: A
authors.lastname: Upponi
authors.forename: Usha
authors.initials: U
authors.lastname: Gopinathan
authors.forename: Rishita
authors.initials: R
authors.lastname: Nutheti
authors.forename: Prashant
authors.initials: P
authors.lastname: Garg
mesh_terms: D015823:Acanthamoeba Keratitis / Q000175:diagnosis; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000935:Antifungal Agents / Q000627:therapeutic use; D001424:Bacterial Infections / Q000175:diagnosis* / Q000188:drug therapy*; D003315:Cornea / Q000382:microbiology / Q000469:parasitology; D006801:Humans; D007634:Keratitis / Q000382:microbiology* / Q000469:parasitology; D008828:Microbiological Techniques; D009181:Mycoses / Q000175:diagnosis* / Q000188:drug therapy*; D011446:Prospective Studies
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents