Fluoroquinolone resistance in bacterial isolates from ocular infections: Trend in antibiotic susceptibility patterns between 2005-2020

Purpose: To assess the fluoroquinolone resistance pattern and trends among bacterial isolates from ocular infections over a 16?year period and explore alternative antibiotics in fluoroquinolone?resistant strains. Methods: In this retrospective, longitudinal study, the microbiology laboratory records of patients with different ocular infections diagnosed at an eye institute in central India from 2005–2020 were reviewed to determine the pattern of fluoroquinolone (ciprofloxacin, ofloxacin, gatifloxacin, and moxifloxacin) resistance. Antibiotic susceptibility testing was done using the Kirby–Bauer disc diffusion method. Results: In 725 Gram?positive bacteria, the resistance of ciprofloxacin, ofloxacin, gatifloxacin, and moxifloxacin was 55.9% (95% confidence interval [CI]: 52.2 – 59.6), 42.7% (95% CI: 39.0 – 46.4), 47.6% (95% CI: 43.9 – 51.3), and 45.6% (95% CI: 41.7–49.5), respectively. In 266 Gram?negative bacteria, the resistance of ciprofloxacin, ofloxacin, gatifloxacin, and moxifloxacin was 57.9% (95% CI: 51.9 – 63.9), 56.0% (95% CI: 49.7 – 62.1), 59.9% (95% CI: 53.8 – 66.0), and 74.3% (95% CI: 68.3 – 80.2), respectively. A declining trend in resistance to ciprofloxacin (P < 0.001), ofloxacin (P < 0.001), and moxifloxacin (P < 0.001) was seen in Gram?positive bacteria, whereas a reduction in resistance to only moxifloxacin (P = 0.04) was seen in Gram?negative bacteria. In fluoroquinolone?resistant Gram?positive bacteria, cefuroxime exhibited the highest susceptibility, whereas in fluoroquinolone?resistant Gram?negative bacteria, colistin exhibited the highest susceptibility. Conclusion: Fluoroquinolone resistance was high among bacteria from ocular infections in central India, but a declining trend in resistance to some of the fluoroquinolones was observed in recent times. Cefuroxime and colistin emerged as alternatives in fluoroquinolone?resistant Gram?positive and Gram?negative bacterial infections, respectively.

Antibiotic susceptibility pattern of bacterial isolates from microbial keratitis in North and Central India: A multi centric study

Purpose: This study was conducted to examine microbiological profile with their antibiotic sensitivity in cases of bacterial keratitis in north and central India to ensure appropriate use of antibiotics. Methods: The microbiology laboratory records of 228 patients with culture?proven bacterial keratitis from 1st January to 31st December 2019 were analyzed. Cultured bacterial isolates were subjected to antimicrobial susceptibility testing to antibiotics commonly used in the treatment of corneal ulcer. Chi?squared or Fisher’s exact test were applied to check the significance of difference between the susceptibility levels of antibiotics. Results: The prevalence of Staphylococcus aureus and Pseudomonas aeruginosa–induced keratitis was higher in northern India, whereas that by Streptococcus pneumoniae was more prevalent in central India. In central India, 100% of S. pneumoniae isolates were found to be sensitive to ceftriaxone compared to 79% in northern India (P = 0.017). In comparison to 67% of isolates from north India, 15% of S. aureus isolates from central India were found to be sensitive to ofloxacin (P = 0.009). Similarly, 23% of isolates from central India were found sensitive to amikacin compared to 65% of isolates from north India (P = 0.012). P. aeruginosa isolates from central India were found to be sensitive to ceftazidime in 63% of cases compared to 21% of isolates from north India (P = 0.034). Conclusion: Prevalence of bacteria and their susceptibility to antibiotics are not uniform across geography. Vancomycin remained the most effective drug in all gram?positive coccal infections. S. aureus susceptibility to amikacin was significantly greater in north India. P. aeruginosa showed less susceptibility as compared to previous reports.

Impact of comprehensive eye examination in identifying the ocular co-morbidities in patients screened for cataract surgery through the out-reach activities

Purpose: To evaluate the impact of comprehensive eye examination in identifying the ocular co?morbidities in patients presenting for cataract surgery through the community screening program. Methods: This was a hospital?based retrospective cross?sectional descriptive study in a tertiary eye care institute. Comprehensive eye examination was performed for all patients screened for cataract surgery through the out?reach activities. Patients suspected to have any ocular co?morbidity were revaluated by sub?specialty trained ophthalmologists, and further management was planned. The demographic details of patients, sub?specialty consultation, final diagnosis, and type of the treatment received by these patients were recorded. Results: During the study period, 4022 patients were referred to the base hospital for cataract surgery, of whom 922 (22.9%) needed a specialist opinion. Glaucoma (238) and retinal disorders (232) constituted half (51%) of these referrals. There were 313 (33.9%) patients having co?morbidities because of corneal, oculoplastic, and neuro?ophthalmic conditions. After specialist review, 397 (43.1%) patients underwent only cataract surgery, 55 patients (5.9%) underwent combined surgeries, and 168 (18.2%) patients underwent other procedures. Cataract surgery was not performed in 470 (50.9%) patients, of which 302 were prescribed glasses or managed medically. Conclusion: All patients screened for cataract surgery through out?reach programs require a comprehensive eye examination to identify ocular diseases other than cataract. Provisions must be made for providing alternative or additional treatment in those with various ocular co?morbidities.

Clinical differentiation of Pythium keratitis from fungal keratitis and development of a scoring system

Purpose: To differentiate Pythium keratitis from fungal keratitis using clinical signs, to explore usefulness of various signs as diagnostic prognosticators, and develop a clinical scoring system. Methods: A retrospective review of medical records and archived clinical photographs of patients with culture?positive Pythium keratitis and hyaline filamentous fungal keratitis was conducted at a tertiary eye institute to explore characteristics of ulcers that may aid diagnosis. Results: Full?thickness corneal stromal keratitis (P = 0.055), a dry ulcer surface (P = 0.010), tentacles (P < 0.0001), intrastromal dots (P < 0.0001), ring infiltrates (P = 0.024), reticular patterns (P < 0.0001), and peripheral furrows (P < 0.0001) were clinical signs associated with Pythium keratitis. Multiple regression analysis identified tentacles (odds ratio: 24.1, 95% confidence interval (CI): 3.8–158.1, P = 0.001) and peripheral furrows (odds ratio: 60.6, 95% CI: 5.1–712.3, P = 0.001) as independent diagnostic prognosticators for Pythium keratitis. The positive and negative likelihood ratios of a dry ulcer surface, tentacles, intrastromal dots, ring infiltrates, reticular patterns, and peripheral furrows predicting Pythium keratitis were 1.6, 13.6, 17.9, 4.3, 30.7, 15.3 and 0.4, 0.4, 0.7, 0.9, 0.6 and 0.8, respectively. The presence of two or more of these clinical signs (excluding a dry ulcer surface) had a sensitivity of 55.6% and a false positive rate of 1.4%. Conclusion: Tentacles, intrastromal dots, ring infiltrates, reticular patterns, and peripheral furrows are clinical signs to be considered for the diagnosis of Pythium keratitis and the presence of two or more signs has a very low false positive rate

Multi‑drug resistant Pseudomonas aeruginosa keratitis and its effective treatment with topical colistimethate.

The purpose was to evaluate the clinical outcome in multi‑drug resistant Pseudomonas aeruginosa (MDR‑PA) bacterial keratitis and report the successful use of an alternative antibiotic, topical colistimethate in some of them. The medical records of 12 culture‑proven MDR‑PA keratitis patients, all exhibiting in vitro resistance by Kirby–Bauer disc diffusion method to ≥ three classes of routinely used topical antibiotics were reviewed. Eight patients were treated with 0.3% ciprofloxacin or ofloxacin, 1 patient with 5% imipenem/cilastatin and 3 patients with 1.6% colistimethate. The outcomes in 8 eyes treated with only fluoroquinolones were evisceration in 4 eyes, therapeutic corneal graft in 1 eye, phthisis bulbi in 1 eye, and no improvement in 2 eyes. The eye treated with imipenem/cilastin required a therapeutic corneal graft. All the three eyes treated with 1.6% colistimethate healed. Colistimethate may prove to be an effective alternative antibiotic in the treatment of MDR‑PA keratitis.

Granulomatous inflammation in Acanthamoeba sclerokeratitis.

This report describes the histopathological findings in a patient with Acanthamoeba sclerokeratitis (ASK). A 58-year-old patient with ASK underwent enucleation and sections of the cornea and sclera were subjected to histopathology and immunohistochemistry with monoclonal mouse antihuman antibodies against T cell CD3 and B cell CD20 antigens. Hematoxylin and Eosin stained sections of the cornea revealed epithelial ulceration, Bowman's membrane destruction, stromal vascularization, infiltration with lymphocytes, plasma cells, and granulomatous inflammation with multinucleated giant cells (MNGC). The areas of scleritis showed complete disruption of sclera collagen, necrosis and infiltration with neutrophils, macrophages, lymphocytes, and granulomatous inflammation with MNGC. No cyst or trophozoites of Acanthamoeba were seen in the cornea or sclera. Immunophenotyping revealed that the population of lymphocytes was predominantly of T cells. Granulomatous inflammation in ASK is probably responsible for the continuance and progression of the scleritis and management protocols should include immunosuppressive agents alongside amoebicidal drugs.

Fungal keratitis in Lattice dystrophy.

We report a case of fungal keratitis occurring in a patient with lattice dystrophy. A 57-year-old farmer presented with a corneal ulcer following probable entry of paddy husk in the right eye, of one month duration. Corneal scraping revealed pigmented fungal filaments while culture grew Alternaria alternata. Treatment with 5% natamycin eye drops and 1% atropine healed the infection in four weeks. We would like to draw attention to the fact that the cornea in lattice dystrophy is prone to frequent erosions and is a compromised epithelial barrier to invasion by microorganisms. Patients must be made aware of this fact and should seek attention at the earliest following any trivial trauma. Management of minor corneal abrasions in them should be directed at healing the epithelium with adequate lubricants and preventing infection with topical antibiotic prophylaxis.

"String of pearls" following Nd:YAG laser posterior capsulotomy.

Posterior capsular re-opacification can occur following Nd-YAG capsulotomy. This necessitates multiple capsulotomies with its potential complications. We report one such case and discuss possible predisposing factors and preventive measures for this condition.