David C. Ritterband

Gatifloxacin and moxifloxacin: an in vitro susceptibility comparison to levofloxacin, ciprofloxacin, and ofloxacin using bacterial keratitis isolates

PURPOSE We compared the in vitro susceptibility patterns and the minimum inhibitory concentrations (MICs) of gatifloxacin (GAT) and moxifloxacin (MOX) (fourth-generation fluoroquinolones) to ciprofloxacin (CIP) and ofloxacin (OFX) (second-generation fluoroquinolones) and levofloxacin (LEV; third-generation fluoroquinolone) using bacterial keratitis isolates. The goal was to determine whether the fourth-generation fluoroquinolones offer any advantages over the second- and third-generation fluoroquinolones. DESIGN Experimental laboratory investigation. In contrast to an epidemiologic prevalence study, this study was designed to compare the relative susceptibility of each bacterial group to different fluoroquinolones by deliberate selection of representative isolates that were both susceptible and resistant to second-generation fluoroquinolones. METHODS In retrospect, the MICs of 177 bacterial keratitis isolates were determined to CIP, OFX, LEV, GAT, and MOX using E tests. A relative susceptibility analysis was performed for each bacterial group that included separate bacterial groups that were resistant to second-generation fluoroquinolones. The NCCLS susceptibility patterns and the MICs were compared statistically. Comparing MICs, the antibiotic with the lower MICs has greater antibacterial activity. RESULTS For most keratitis isolates, there were no susceptibility differences among the five fluoroquinolones. The fourth-generation fluoroquinolones did, however, demonstrate increased susceptibility for Staphylococcus aureus isolates that were resistant to CIP, LEV and OFX. In general, CIP demonstrated the lowest MICs for gram-negative bacteria. The MICs for fourth-generation fluoroquinolones were statistically lower than the second-generation fluoroquinolones for all gram-positive bacteria tested. Comparing the two fourth-generation fluoroquinolones, MOX demonstrated lower MICs for most gram-positive bacteria, whereas GAT demonstrated lower MICs for most gram-negative bacteria. CONCLUSIONS Based on in vitro testing, the fourth-generation fluoroquinolones may offer some advantages over those currently available for the treatment of bacterial keratitis. Clinical studies will be required to confirm these results.

Bleb-related ocular infection in children after trabeculectomy with mitomycin C

OBJECTIVE The purpose of the study is to report the clinical course of bleb-related ocular infection in children after trabeculectomy with adjunctive mitomycin C. DESIGN The study design was a retrospective review of all patients with a diagnosis of bleb-related ocular infection after trabeculectomy with adjunctive mitomycin C. PARTICIPANTS Three children were identified in whom late postoperative bleb-related ocular infection developed. INTERVENTION Treatment consisted of vitreous biopsy with intravitreous antibiotic and corticosteroid injection and/or bleb culture with topical and intravenous antibiotic administration. MAIN OUTCOME MEASURES Visual acuity and intraocular pressure were measured. RESULTS Bleb-related ocular infection developed an average of 16.7 +/- 10.9 months after trabeculectomy (range, 4-23 months). The mean age at presentation was 7.0 +/- 2.6 years (range, 4-10 years). Vitreous cultures were positive for staphylococci in two cases. A bleb culture from the third case also grew staphylococcus. All of the children recovered their initial vision after treatment of infection. However, one lost six lines of vision after a subsequent retinal detachment. Additional glaucoma surgery was required in one patient. CONCLUSIONS Late bleb-related ocular infection may occur in children after trabeculectomy with mitomycin C and is characterized by abrupt onset, bleb infiltration, and rapid progression. Despite early preservation of vision after treatment of infection, significant late visual loss can occur.

The incidence of fungal keratitis and endophthalmitis following penetrating keratoplasty

PURPOSE To determine the incidence of postkeratoplasty fungal endophthalmitis and keratitis at the New York Eye and Ear Infirmary. To determine whether there is a relationship between culture-positive corneoscleral donor material and postoperative infection. METHODS The microbiologic records of corneoscleral donor rims submitted for culture following penetrating keratoplasty at the New York Eye and Ear Infirmary between January 1998 and January 2003 were reviewed. The incidence of rim cultures positive for fungi was tabulated. Clinical outcome measures were recorded for each patient receiving corneal donor tissue. RESULTS Of 2466 donor corneoscleral rims cultured during the study period, 344 were positive for microbial growth (13%). Of those rims with positive cultures, 28 (8.6%) were positive for fungus. All fungi cultured were Candida species. Four of the 28 recipient eyes (14%) who received contaminated donor material went on to develop postkeratoplasty fungal infections. There were no cases of fungal infection in any postkeratoplasty patients in the absence of contaminated donor rims during the study period. Overall, there was a 0.16% incidence of fungal infection (4/2466) following penetrating keratoplasty. There were 18 positive donor rims identified in the first 4 years of the study, but there were 10 cases in the last 10 months of the study. CONCLUSIONS The overall incidence of fungal infection following penetrating keratoplasty is low, but all cases in our study were associated with positive rim cultures. Whether prophylactic antifungal therapy would be of any benefit in the presence of a positive corneoscleral rim culture has not yet been determined.

Boston type 1 keratoprosthesis: the New York Eye and Ear experience

PurposeThe Boston keratoprosthesis has had variable success rates in the past. However, significant modifications to design and management have recently led to successful outcomes. This study was undertaken to evaluate the outcomes of the Boston type 1 keratoprosthesis at our institution.MethodsA retrospective chart review was performed of all Boston type 1 keratoprosthesis procedures conducted at a single practice at the New York Eye and Ear Infirmary from December 2006 to August 2010. Outcome measures included visual acuity, retention rates, and complications.ResultsIn all, 58 eyes of 51 patients who received a Boston type 1 keratoprosthesis were included. The most common indication for the keratoprosthesis was failed penetrating keratoplasty (PK) (81.0%; mean 2.4±1.3 PKs per eye). Glaucoma was the most common comorbidity (75.9%). Pre-operative best corrected visual acuity (BCVA) was <20/400 in 87.9% of eyes. At last follow-up, 43.1% of eyes had a BCVA of 20/200. Retention rate was 87.9% over an average follow-up of 21.5±11.4 months (median 22 months, range 3–47 months). Complications increased with time, with 65.5% of eyes experiencing at least one event by 6 months and 75.9% by 1 year. The most common post-operative complication was retroprosthetic membrane formation (50.0%).ConclusionsThe Boston type 1 keratoprosthesis provides visual recovery for eyes with multiple PK failures or with poor prognosis for primary PK, showing excellent retention rates. However, there is a trend towards a decline in visual acuity with time and the development of late complications, highlighting a need for longer-term studies.

Visually Significant and Nonsignificant Complications Arising From Descemet Stripping Automated Endothelial Keratoplasty

PURPOSE To examine the complications encountered after Descemet stripping automated endothelial keratoplasty (DSAEK) at one institution. DESIGN Retrospective case review. METHODS The first 126 consecutive DSAEKs done at the New York Eye and Ear Infirmary from March 1, 2006 to March 1, 2008 were reviewed. A total of 126 eyes of 113 patients underwent DSAEK. All cases were included regardless of outcome. All complications intraoperatively and postoperatively were recorded. RESULTS Graft detachment was the most common complication, occurring in 22 eyes (17.5%); 17 of these (77%) were successfully repositioned. Idiopathic graft failure occurred in 15 eyes (6%). Other visually significant complications included graft rejection (2 eyes), choroidal effusion (2 eyes), epithelial ingrowth (2 eyes), endophthalmitis (1 eye), pupillary block (1 eye), and suture abscess (1 eye). Twenty-four eyes had non-visually significant complications including decentered lenticles, interface fibers, partial peripheral detachments, retained Descemet membrane, and eccentric trephination. CONCLUSIONS While DSAEK is a viable alternative to penetrating keratoplasty, serious complications may still occur postoperatively. While certain rare complications like endophthalmitis, epithelial ingrowth, and suture abscess may affect vision, more common complications such as decentered lenticles and partial peripheral detachments are less likely to affect visual outcome.

Graft Rejection Following Descemet Stripping Automated Endothelial Keratoplasty: Features, Risk Factors, and Outcomes

PURPOSE To investigate the clinical features, risk factors, and treatment outcomes following immunologic graft rejection in eyes that have undergone Descemet stripping automated endothelial keratoplasty (DSAEK). DESIGN Retrospective case review. METHODS The charts for 353 DSAEK procedures performed at a single clinical practice at the New York Eye and Ear Infirmary from August 2006 to November 2010 were reviewed. Cases with at least 3 months follow-up were included. Outcome measures included rates of graft rejection, clinical findings, treatment outcomes, and risk factor analysis. RESULTS Thirty of 353 DSAEKs developed graft rejection (8.5%). Kaplan-Meier rate of rejection was 6.0% at 1 year (n = 175), 14.0% at 2 years (n = 79), and 22.0% at 3 years (n = 39). Rejection episodes occurred between 0.8 and 34 months. Clinical findings included anterior chamber cells, keratic precipitates, endothelial rejection line, and host-donor interface vascularization. Risk factors for development of graft rejection were cessation of postoperative steroid (hazard ratio 5.49, P < .0001) and black race (hazard ratio 2.71, P = .02). Recipient age, sex, surgical indication, glaucoma, postoperative steroid response, corneal neovascularization or peripheral anterior synechiae, graft size, prior keratoplasty in fellow eye, and concurrent or subsequent procedures were not associated with graft rejection. Twenty-two out of 30 rejection episodes (73.3%) resolved with steroid treatment. CONCLUSIONS Graft rejection is an important complication following DSAEK. In contrast to penetrating keratoplasty, rejection following DSAEK is almost exclusively endothelial. Among risk factors traditionally associated with graft rejection, cessation of topical steroids was most significant. Prompt recognition and treatment of DSAEK rejection can lead to favorable outcomes.

An in vitro resistance study of levofloxacin, ciprofloxacin, and ofloxacin using keratitis isolates of Staphylococcus aureus and Pseudomonas aeruginosa

PURPOSE We compared levofloxacin with ciprofloxacin and ofloxacin using the in vitro susceptibilities of Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA) keratitis isolates. DESIGN Retrospective, clinical laboratory study of antibiotic susceptibility among keratitis isolates. PARTICIPANTS Keratitis isolates from 200 patients with either SA or PA keratitis. METHODS Minimum inhibitory concentrations (MICs) were determined for levofloxacin, ofloxacin, and ciprofloxacin for 93 SA keratitis isolates (68 fluoroquinolone-resistant and 25 susceptible, as determined by disk diffusion) and 107 PA keratitis isolates (13 fluoroquinolone-resistant and 94 susceptible). National Committee for Clinical Laboratory Standards susceptibilities were determined and analyzed statistically. Time kill studies were determined for fluoroquinolone-susceptible and -resistant isolates to all antibiotics at 8 microg/ml. The killing rates were determined by regression, and the colony count decreases were analyzed. MAIN OUTCOME MEASURES The susceptibilities and potencies of levofloxacin, ciprofloxacin, and ofloxacin to SA and PA were determined from the MICs. Time kill studies determined the killing rates and decreases in colony counts. RESULTS The fluoroquinolone-resistant SA susceptibilities to levofloxacin, ofloxacin, and ciprofloxacin were only 22%, 10%, and 3%, respectively. The fluoroquinolone-susceptible SA were 100% susceptible to all antibiotics, with levofloxacin demonstrating the best potency. The fluoroquinolone-resistant PA were resistant to all antibiotics. The fluoroquinolone-susceptible PA isolates were highly susceptible to levofloxacin, ofloxacin, and ciprofloxacin, with ciprofloxacin demonstrating the highest potency. For fluoroquinolone-susceptible SA and PA, the time kill studies determined that the killing rates and decreases in colony counts were equivalent for all three antibiotics tested. The time kill studies demonstrated no colony count decreases for the fluoroquinolone-resistant SA and PA. CONCLUSIONS Taken together, our susceptibility and time kill data failed to demonstrate convincing differences in the susceptibility of SA and PA keratitis isolates to levofloxacin, ciprofloxacin, and ofloxacin. In general, bacterial isolates that were resistant to ciprofloxacin and ofloxacin were also resistant to levofloxacin.

Molecular characterization, biofilm analysis and experimental biofouling study of Fusarium isolates from recent cases of fungal keratitis in New York State

BackgroundTo characterize Fusarium isolates from recent cases of fungal keratitis in contact lens wearers, and to investigate fungal association with MoistureLoc solution.MethodsWe studied six fungal isolates from recent cases of keratitis in New York State. The isolates were characterized by nucleotide sequencing and phylogenetic analyses of multiple genes, and then typed using minisatellite and microsatellite probes. Experimental fungal biofilm formation was tested by standard methods. MoistureLoc solutions were tested in biofouling studies for their efficacy in elimination of Fusarium contamination.ResultsFusarium solani – corneal ulcers (2 isolates), lens case (1 isolate), and F. oxysporum – corneal ulcer (1 isolate), eye (1 isolate), were recovered from five patients. An opened bottle of MoistureLoc solution provided by a patient also yielded F. solani. Two distinct genotypes of F. solani as well as of F. oxysporum were present in the isolated strains. Remarkably, F. solani strains from the lens case and lens solution in one instance were similar, based on phylogenetic analyses and molecular typing. The solution isolate of F. solani formed biofilm on contact lenses in control conditions, but not when co-incubated with MoistureLoc solution. Both freshly opened and 3-month old MoistureLoc solutions effectively killed F. solani and F. oxysporum, when fungal contamination was simulated under recommended lens treatment regimen (4-hr). However, simulation of inappropriate use (15 – 60 min) led to the recovery of less than 1% of original inoculum of F. solani or F. oxysporum.ConclusionTemporary survival of F. solani and F. oxysporum in MoistureLoc suggested that improper lens cleaning regimen could be a possible contributing factor in recent infections.

Failed descemet-stripping automated endothelial keratoplasty grafts: a clinicopathologic analysis.

PURPOSE To describe the clinicopathologic findings in failed Descemet-stripping automated endothelial keratoplasty (DSAEK) grafts. DESIGN Retrospective, interventional case series. METHODS SETTING New York Eye and Ear Infirmary. STUDY POPULATION Twenty-one patients with 22 failed DSAEK grafts treated between March 1, 2006 and February 1, 2008. INTERVENTION Repeat DSAEK or penetrating keratoplasty were performed in the eyes with failed grafts. All failed grafts were examined histopathologically. MAIN OUTCOME MEASURES Histopathologic parameters studied in failed DSAEK grafts included endothelial cell count, interface characteristics, retrocorneal membrane formation, inflammation, and immunoreactivity for herpes simplex virus type 1 (HSV-1) antigen. RESULTS DSAEK failure was strongly associated with postoperative lenticle dislocation. Graft failure was primary in 19 DSAEKs and secondary to rejection, eccentric trephination with epithelial ingrowth, or bacterial infection in the remaining 3. All failed grafts demonstrated endothelial hypocellularity and stromal edema. Additional findings included stromal inflammation (68%), interface fibrosis (50%), retrocorneal membrane (36%), unplanned retention of Descemet membrane (14%), immunoreactivity for HSV-1 (14%), paucicellular stroma (14%), and uneven trephination with epithelial ingrowth (5%). CONCLUSIONS Most DSAEK failures are secondary to endothelial cell loss. Other contributing factors include interface fibrosis, retrocorneal membrane formation, retained host Descemet membrane, uneven trephination, epithelial ingrowth, graft rejection, and infection.

Penetrating keratoplasty with pars plana glaucoma drainage devices.

Purpose: To study the outcome of penetrating keratoplasty (PK) in eyes undergoing simultaneous insertion or repositioning of a glaucoma drainage device (GDD) through the pars plana. Methods: The medical records of all patients who underwent PK and primary placement or repositioning of a GDD through the pars plana from April 1, 1997, through December 1, 2005, were reviewed. Intraocular pressure (IOP) control was defined as maintenance of IOP ≥5 and ≤21 mm Hg (without loss of light perception vision or needing further glaucoma surgery). Kaplan-Meier life table survival analysis was used to estimate the success of graft survival (clarity) and glaucoma control. Results: Eighty-three eyes of 80 patients (34 men and 46 women) were identified. Mean follow-up was 16 months (range, 6-96 months). PK and pars plana vitrectomy were performed with primary pars plana GDD insertion (57 eyes) or tube repositioning from the anterior chamber to pars plana (26 eyes). Grafts remained clear in 93% of eyes (76/83) at 6 months, 87% (56/66) at 1 year, and 59% (19/32) at 2 years. IOP was controlled in 87% (72/83) of eyes at 6 months, 95% (57/63) at 1 year, and 83% (20/24) at 2 years. Conclusions: PK with simultaneous pars plana GDD repositioning or placement showed comparable short- and long-term IOP control to that of previous studies with limbal-based GDD. The rate of corneal graft failure and the rate of immunologic rejection were comparable to or lower than those reported in other series with primary limbal-based GDD.