Madhukar K. Reddy

Comparison of Ciprofloxacin Ophthalmic Solution 0.3% to Fortified Tobramycin-Cefazolin in Treating Bacterial Corneal Ulcers

PURPOSE The purpose of the study is to compare the clinical efficacy and safety of ciprofloxacin ophthalmic solution 0.3% (Ciloxan) with a standard therapy regimen (fortified tobramycin, 1.3%-cefazolin, 5.0%) for treating bacterial corneal ulcers. METHODS This randomized, parallel group, double-masked, multicenter study was conducted in 324 patients at 28 centers in the United States, Europe, and India. Patients were randomized into 2 treatment groups: 160 to ciprofloxacin and 164 to fortified tobramycin-cefazolin. Positive microbiologic cultures were obtained in 188 (58%) of 324 patients. Of these, 176 patients met protocol criteria and were evaluated for treatment efficacy: 82 in the ciprofloxacin group and 94 in the standard therapy group. The dosing schedule for both treatment groups was 1 to 2 drops of the first study medication (ciprofloxacin or fortified tobramycin) every 30 minutes for 6 hours, then hourly for the remainder of day 1; 1 to 2 drops every hour on days 2 and 3; 1 to 2 drops every 2 hours on days 4 and 5, followed by 1 to 2 drops every 4 hours on days 6 to 14. The second medication (ciprofloxacin or cefazolin) was instilled 5 to 15 minutes after the first drug, following the same dosing frequency. Physicians judgment of clinical success, cure rate, changes in ocular sings, and symptoms and the rate of treatment failures were the primary efficacy criteria. RESULTS Topical ciprofloxacin monotherapy is equivalent clinically and statistically to the standard therapy regimen of fortified antibiotics. No statistically significant treatment differences were found between ciprofloxacin (91.5%) and standard therapy (86.2%) in terms of overall clinical efficacy (P = 0.34). Similarly, no differences were noted in resolution of the clinical signs and symptoms (P > 0.08) or the time to cure (P = 0.55). The incidence of treatment failures was less in the ciprofloxacin group (8.5%) compared with the standard therapy group (13.8%). Significantly fewer patients treated with ciprofloxacin reported discomfort than did patients treated with the standard therapy regimen (P = 0.01). CONCLUSION Ciprofloxacin ophthalmic solution 0.3% monotherapy is equivalent clinically and statistically to standard therapy (fortified tobramycin-cefazolin) for the treatment of bacterial corneal ulcers and produces significantly less discomfort.

Microbial keratitis in children.

OBJECTIVE Microbial keratitis is a major cause of corneal blindness worldwide. This problem is particularly relevant to children, because most of their visual life is ahead of them, and they are uniquely at risk for irreversible ocular deficits, such as those resulting from amblyopia. The objective of this study was to determine the etiologic agents and predisposing factors in childhood infectious keratitis and to examine the outcome of treatment in terms of structure and visual acuity. DESIGN The study design was a retrospective cases series. PARTICIPANTS The authors studied 113 eyes in 107 children 16 years of age and younger who were treated for (nonviral) microbial keratitis at the LV Prasad Eye Institute in Hyderabad, India, during the 4.5-year period between February 1, 1991, and June 30, 1995. INTERVENTION The patients who met the following criteria were included in the study: (1) corneal stromal infiltrate was present on slit-lamp examination; and (2) a corneal scraping was taken at the time of examination for suspected microbial keratitis. MAIN OUTCOME MEASURES Etiologic micro-organisms, predisposing factors, treatment method, structural treatment outcome, and visual acuity treatment outcome of the infectious keratitis episode were measured. RESULTS The principal predisposing factors identified in this study were trauma (21.2%), ocular disease (17.7%), systemic disease (15.9%), and prior penetrating keratoplasty in the same eye (8.8%). Vitamin A deficiency was an important factor within the category of severe systemic disease, and contact lens wear was not involved in any of the cases. A total of 85 organisms were isolated in cultures of corneal scrapings from 64 (56.6%) of the 113 cases. Staphylococcus species (43.7%), Streptococcus pneumoniae (18.8%), and fungi (17.2%) were the most common isolates. Eighteen eyes (15.9%) required surgery, and 28 (36.4%) of the 77 patients on whom visual acuity was assessed at last follow-up achieved an unaided visual acuity of 20/60 or better at last follow-up. CONCLUSION This work represents the largest recent study on childhood (nonviral) microbial keratitis, its management, and treatment outcomes. In this study, amblyopia is highlighted as a potentially significant sequela of childhood microbial keratitis. Identification of the appropriate predisposing factors, etiologic microbial organisms, and treatment outcome from this study may aid in early recognition and treatment of microbial keratitis in children.

Contact lens-induced peripheral ulcers with extended wear of disposable hydrogel lenses: histopathologic observations on the nature and type of corneal infiltrate.

PURPOSE Contact lens-induced peripheral ulcer (CLPU), a sudden-onset adverse event observed with extended wear of hydrogel lenses, is characterized by a single, small, circular, focal anterior stromal infiltrate in the corneal periphery or midperiphery. The condition is always associated with a significant overlying epithelial loss and resolves in a scar. The aim was to determine, by using histopathologic techniques, the nature and type of the corneal infiltrate of these events. METHODS Three CLPUs observed in three patients using disposable hydrogel lenses on an extended-wear schedule were examined. The eye was topically anesthetized, and a corneal section including all of the infiltrate was taken. A small triangular piece of conjunctiva immediately adjacent to the infiltrate was sectioned. The tissue was immediately fixed, processed, stained using hematoxylin and eosin and periodic acid-Schiff stains, and examined by using light microscopy. RESULTS The diameter of these three corneal infiltrates varied from 0.3 to 0.6 mm. Histopathology of the corneal sections revealed a focal epithelial loss corresponding to the infiltrated stroma in all three patients. The adjacent epithelium was thinned. Bowmans layer was intact in two patients and had a localized area of loss in the remaining patient. The anterior stroma was densely infiltrated with polymorphonuclear leukocytes and had focal areas of necrosis. The infiltration was most dense in the region immediately underlying Bowmans layer. No other infiltrative cell type was seen in any of the sections. Histopathology of the conjunctiva revealed features consistent with normal conjunctival tissue. CONCLUSIONS On histopathology of CLPU, distinctive features (i.e., focal corneal epithelial loss, an intact Bowmans membrane, and a localized infiltration of the anterior stroma with polymorphonuclear leukocytes) were seen. These features suggest that the event is an acute inflammatory process and probably noninfective in nature.

Clinicomicrobiological review of Nocardia keratitis

Purpose To present the clinical profile, laboratory results, and outcome of treatment in 16 patients with Nocardia keratitis. Methods A retrospective review of 16 culture-proven cases of Nocardia keratitis was done. Clinical and microbiologic data were analyzed. Results Nocardia constituted 1.7% of laboratory-confirmed bacterial keratitis and was seen predominantly in male subjects (13 of 16) with a mean age of 39.1 years. Although the predisposing factor was unknown in the majority, a definite history of trauma was present in four (25%) cases. Patchy stromal infiltrates were seen in 12 patients. Wreath pattern of infiltrates (six of 16) and hypopyon (nine of 16) were notable features. Nocardia was detectable in corneal scrapings of 10 patients with Gram stain and all patients with 1% acid-fast preparation (six of six). Nocardia asteroides was the causative agent in all except one (N. caviae). All isolates were sensitive to gentamicin; however, topical 30% sulfacetamide was the preferred drug for treatment. Favorable outcome (healed scar) was achieved in 11. Conclusion Although Nocardia keratitis is a rare condition, a high index of clinical suspicion should be kept in agricultural workers or in patients with trauma who have patchy stromal infiltrates. Sulfonamides are the initial drug of choice, and gentamicin could be an effective alternative. If recognized early, Nocardia keratitis responds to medical treatment with good visual recovery.

Heparin-surface-modified intraocular lenses in pediatric cataract surgery: Prospective randomized study

PURPOSE To evaluate the performance of heparin-surface-modified (HSM) intraocular lenses (IOLs) in pediatric eyes after cataract surgery. SETTING L.V. Prasad Eye Institute, Hyderabad, India. METHODS This prospective, randomized, double-masked, controlled clinical trial comprised 90 children aged 2 to 14 years with cataract. The patients were consecutively randomized to receive an HSM (Group 1) or an unmodified (Group 2) poly(methyl methacrylate) (PMMA) IOL. Extracapsular cataract extraction (ECCE) with IOL implantation was performed in children 8 years and older and ECCE with primary posterior capsulotomy, anterior vitrectomy, and IOL implantation in children younger than 8 years. Outcome parameters were inflammatory cell deposits on the IOL surface, posterior synechias, and anterior chamber reaction. RESULTS Follow-up data were available for 73, 70, 60, and 68 patients at 1 week, 1 month, 3 months, and 6 months, respectively. Significantly fewer cell deposits were noted in Group 1 at 1, 3, and 6 months (P < .001). Synechia formation and anterior chamber reaction were comparable in the 2 groups. CONCLUSION The lower incidence of inflammatory cell deposit formation in eyes with HSM PMMA IOLs indicates that these IOLs have greater bicompatibility than unmodified IOLs in pediatric cataract surgery.

Co-occurrence of pneumococcal keratitis and dacryocystitis.

PURPOSE To evaluate the specific risk factors responsible for the development of pneumococcal keratitis. METHODS In a retrospective analysis of 383 patients of culture-proven bacterial keratitis, seen between 1991 and 1995, 139 had monobacterial isolates on culture. We analyzed the various predisposing factors in these patients, with special emphasis on the patency of nasolacrimal drainage system. RESULTS Of the 139 patients with monobacterial keratitis, 48 (group 1) grew Streptococcus pneumoniae in culture. In the remaining 91 patients (group 2), Pseudomonas (18), coagulase-negative Staphylococci (15), Staphylococcus epidermidis (23), Staphylococcus aureus (16), Corynebacterium species (12), and others (seven) were isolated. Trauma was found to be a predisposing factor in 12 patients of group 1 and 27 patients of group 2 (p = 0.5601). Twelve (25%) patients of group 1 revealed chronic dacryocystitis, and nine of them underwent sac excision. On the contrary, only three patients of group 2 demonstrated dacryocystitis (p = 0.0003). CONCLUSION These results underscore the importance of assessing the patency of lacrimal drainage system in patients with infectious keratitis, especially of pneumococcal origin.

Antimicrobial effect of ciprofloxacin, povidone-iodine, and gentamicin in the decontamination of human donor globes.

Purpose Clinical research addressing the issue of donor globe decontamination is yet to establish convincing data for the optimal choice of an antimicrobial agent. Methods In a donor-globe decontamination study, the antimicrobial effectiveness of a fluoroquinolone antibiotic (ciprofloxacin, 0.3%) was evaluated for the first time and compared with povidone—iodine (P-I, 5%) and gentamicin (0.3%). Results Ciprofloxacin and gentamicin were found to be less effective than P-I (p < 0.05) in converting culture-positive donor globes to culture negative. In eliminating coagulase-negative staphylococci that predominated the bacterial spectrum, again P-I scored better than ciprofloxacin (p = 0.003) and gentamicin (p = 0.006). Overall, P-I performed better than the other two in the 3-min decontamination procedure. Decontamination was carried out with the same agent for 15 min to assess the effect of duration of decontamination on the antimicrobial activity of P-I. With time, there was no significant increase in the antimicrobial efficacy of the agent except for Corynebacterium species. Conclusion P-I continues to be the preferred agent for decontaminating donor globes. Whereas a contact of 3-min duration between P-I and donor globe remains satisfactory in decontamination procedures, corneal tolerance of this procedure needs investigation.

Clinicohistopathological findings of gelatinous droplike corneal dystrophy among Asians

We describe the findings in nine Asian-Indian patients with gelatinous droplike corneal dystrophy (GDCD). Most patients showed initial signs of bilateral decreased vision and photophobia at an early age. The siblings were affected in four cases, and parental consanguinity was recorded in seven cases. We classified the disease into three forms based on clinicopathologic findings. Clinically, the mild form of the disease was evidenced by central subepithelial, whitish-yellow, nodular lesions that corresponded to the subepithelial nodular deposits seen histologically. In the moderate form, the lesions coalesced, forming central, diffuse subepithelial lesions with superficial vascularization. On histology, the amyloid deposits assumed a sheetlike distribution in the subepithelial regions and in the superficial stroma. Aggregates of chronic inflammatory cells and stromal neovascularization were seen in the adjacent stroma. The severe form presented as diffuse, whitish opacification of the cornea with extensive neovascularization and scarring. Histologically this form was characterized by a visible plaque of vascularized scar tissue that partly replaced the stroma and enveloped the amyloid deposits. Frequent, early recurrence of the disease was noted in the grafts. This study provides a detailed clinicopathologic description of GDCD from the Indian subcontinent. We also discuss previously unreported findings from the most advanced stage of the disease.

Posterior capsule dehiscence during phacoemulsification and manual extracapsular cataract extraction: comparison of outcomes

Purpose: To compare the intraoperative behavior and postoperative outcomes of posterior capsule dehiscence during phacoemulsification and during manual extracapsular cataract extraction (ECCE). Setting: L.V. Prasad Eye Institute, Hyderabad, India. Methods: This study was a retrospective chart review of consecutive cases of posterior capsule dehiscence over 2 years in patients having phacoemulsification or manual ECCE. A chi‐square test was used for statistical comparison of the results in the 2 groups. Results: In the 127 eyes with posterior capsule dehiscence, the incidence of vitreous prolapse was comparable between the 2 groups (phacoemulsification, 61.6%; ECCE, 62.7%). In the phacoemulsification group, vitreous prolapse occurred more frequently if nuclear fragments were present at the time of posterior capsule dehiscence than if they were present during cortex removal (P = .05). Posterior dislocation of nuclear fragments occurred in 4 eyes in the phacoemulsification group. Increased anterior uveitis in the early postoperative period occurred more frequently in the ECCE group (P = .02). The visual outcomes were similar between the 2 groups. Conclusion: Even though differences existed between the intraoperative factors influencing the management of posterior capsule dehiscence during phacoemulsification and ECCE, the final anatomic and visual outcomes were comparable.

Influence of intraocular lens haptic material on bacterial isolates from anterior chamber aspirate

Purpose: To determine whether intraocular lens (IOL) type affects the bacterial count in anterior chamber aspirates obtained immediately after cataract surgery. Setting: L.V. Prasad Eye Institute, Hyderabad, India. Methods: This in vivo study evaluated two groups of eyes that had uneventful cataract extraction and implantation of one of two types of IOLs: all‐poly(methyl methacrylate) (PMMA) (n = 73) or polypropylene haptic (n = 83). Anterior chamber fluid aspirates (0.1 mL) were obtained with a 30 gauge cannula at the end of surgery and inoculated onto chocolate agar and in thioglycolate broth. Microbiology evaluation was performed using standard methods. Results: Seven eyes (9.5%) with all‐PMMA IOLs and 21 (25.3%) with polypropylene haptic IOLs were positive for bacterial isolates (P = .0322; chi‐square test). Mean colony count (±SD) was 11.43 ± 3.78 and 13.16 ± 4.78 colony‐forming units/milliliter in the PMMA and polypropylene haptic IOL groups, respectively. No eye developed endophthalmitis. Conclusion: Polypropylene haptic IOLs were associated with a significant increase in bacteria in the anterior chamber.