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Savitri Sharma

Publications and source records attributed to Savitri Sharma.

42 records · Page 3Linked to original sources

Clinical presentation of microbial keratitis with daily wear frequent-replacement hydrogel lenses: a case series.

Microbial keratitis (MK) is a serious complication associated with contact lens wear. In this case series we report three clinical presentations of MK associated with daily-wear monthly-replacement soft contact lenses. All of these patients were using vifilcon A (55% water content, ionic, U.S. Food and Drug Administration [FDA] group IV) monthly-replacement soft contact lenses. A gram-stained smear of the corneal scrapings of two patients showed numerous gram-negative cocci bacilli, and tissue cultures showed significant growth of Pseudomonas aeruginosa. In the third patient, the corneal scrapings showed numerous gram-negative bacilli, along with gram-positive cocci, and tissue culture showed significant growth of Aeromonas species and alpha-hemolytic streptococci. All these cases were resolved by medical therapy. This case series highlights the importance of patient symptoms, clinical features, and microbiologic work-up in making a differentiation between MK and sterile contact lens-induced peripheral ulcer (CLPU). A high index of suspicion and close follow-up care will avoid misdiagnosis and reduce complications.

Adolescent↗

Diagnosis of herpes simplex virus-1 keratitis: comparison of Giemsa stain, immunofluorescence assay and polymerase chain reaction.

PURPOSE: To evaluate three different diagnostic tests against the gold standard of viral isolation, in the diagnosis of HSV-1 keratitis. METHODS: Corneal scrapings from 170 patients with clinically suspected HSV keratitis were tested by; 1) Giemsa staining procedure for the presence of multinucleated giant cells and lymphocytes, 2) immunofluorescence assay for HSV-1 antigen, 3) polymerase chain reaction (PCR) for HSV-1 DNA and 4) virus isolation by shell vial culture in SIRC (Rabbit corneal epithelial cell line). The results of the former three tests were compared among 14 cases that were culture positive and 156 cases that were culture negative for HSV-1. RESULTS: The sensitivity of PCR was 100%, while IFA and Giemsa had sensitivities of 85.7% and 57.1% respectively. The specificity of PCR, IFA and Giemsa were found to be 67.9%, 85.3% and 85.9% respectively. CONCLUSIONS: In the present study, a combination of PCR and immunofluorescence assay appears to be the most suitable choice of tests for diagnosis of HSV-1 keratitis, while detection of MNGC by Giemsa staining procedure may give us a presumptive diagnosis of suspected viral infection.

Azure Stains↗

Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: an in vitro comparison.

BACKGROUND: To determine the antibacterial activity of newer fluoroquinolones and compare their activity between ciprofloxacin-susceptible and resistant bacterial isolates from patients with keratitis and endophthalmitis. MATERIALS AND METHODS: The minimum inhibitory concentration (MIC) of ciprofloxacin, ofloxacin, levofloxacin, gatifloxacin and moxifloxacin was determined for 123 bacterial isolates, using E test. Among the 123 isolates, 68 were gram-positive (Staphylococcus spp, Streptococcus spp, Corynebacterium spp, Bacillus spp.) and 55 were gram-negative (Pseudomonas aeruginosa). The bacterial isolates were divided into three groups: susceptible/intermediate/resistant to ciprofloxacin. The MIC values for various fluoroquinolones were compared between the three groups and between gram-positive and gram-negative bacteria. RESULTS: For gram-positive isolates, median MICs of fourth generation fluoroquinolones were lower than second generation. The median MIC was lowest for gatifloxacin and moxifloxacin (0.094 mg/ml) in ciprofloxacin-susceptible isolates of gram-positive bacteria. For ciprofloxacin-susceptible gram-negative bacteria, the median MIC of ciprofloxacin (0.19 mg/ml) was significantly lower than ofloxacin, levofloxacin, gatifloxacin and moxifloxacin (1.5, 0.5, 0.5 and 2 mg/ml respectively). Ciprofloxacin-resistant isolates of gram-positive bacteria showed higher MIC of levofloxacin, moxifloxacin and gatifloxacin though they remained susceptible to them. None of the fluoroquinolones were effective against ciprofloxacin-resistant gram-negative bacteria. Overall, for gram-positive bacteria, median MICs of levofloxacin, moxifloxacin and gatifloxacin were below ciprofloxacin, the MIC of gatifloxacin and moxifloxacin was equal for gram-positive bacteria. CONCLUSIONS: Levofloxacin, gatifloxacin and moxifloxacin are statistically more effective against gram-positive bacteria, the latter two being equally effective. Ciprofloxacin remains the most effective fluoroquinolone against gram-negative bacteria.

Eye Infections, Bacterial↗

Comparison of clinical and microbiological profiles in smear-positive and smear-negative cases of suspected microbial keratitis.

PURPOSE: To examine the hypothesis that initial smear examination results have a significant bearing on the management and outcome of suspected microbial keratitis. MATERIALS AND 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.

Acanthamoeba Keratitis↗