In vivo assessment of antimicrobial activity and toxicity of repeated 1% povidone-iodine applications vs a single 5% povidone-iodine application.

PURPOSE: To demonstrate the noninferiority in antimicrobial effectiveness of thrice-repeated applications of 1% povidone-iodine (PI) compared with a single application of 5% PI on the ocular surface in vivo and to evaluate potential toxicity of PI to the corneal epithelium. SETTING: Department of Ophthalmology, Shaare Zedek Medical Center, Jerusalem, Israel. DESIGN: Prospective, randomized, double-blind study. METHODS: Patients randomly received either a single application of 5% PI or repeated irrigations of 1% PI on the ocular surface preoperatively. Bacterial colony counts were quantitatively analyzed by taking standardized conjunctival swabs before and after irrigation, and differences in bacterial colony counts were compared between the 2 groups. The presence of superficial punctate keratopathy was evaluated in all patients by the National Eye Institute grading system. RESULTS: The study comprised 102 eyes of 102 patients. Both 1% and 5% PI yielded a marked decrease in bacterial colonies compared with before application ( P < .001). The repeated application of 1% PI showed a significantly lower bacterial count compared with the single application of 5% PI ( P < .05) and resulted in significantly less damage to the corneal epithelium compared with a single 5% PI application ( P < .001). CONCLUSIONS: Preoperative repeated applications of 1% PI effectively eradicated ocular surface bacteria equal to that of 5% PI with a less deleterious effect on the corneal epithelium. Our findings suggest that 1% PI may be a promising alternative to 5% PI.

Intracameral antibiotics during cataract surgery: efficacy, safety, and cost-benefit considerations.

PURPOSE OF REVIEW: We summarize evidence-based considerations regarding the use of intracameral antibiotics during cataract surgery. RECENT FINDINGS: The use of intraoperative intracameral antibiotics reduced the incidence of postcataract surgery endophthalmitis 3.5-fold, with an odds ratio ranging from 0.14 to 0.19. A survey of the American Society of Cataract and Refractive Surgery showed usage of intracameral injections of antibiotics increased by 16% in the United States between 2014 and 2021. The frequency of vancomycin usage has sharply dropped to 6%, while moxifloxacin is now the dominant choice at 83% among respondents. One analysis showed that 2500 patients need to be treated with intracameral antibiotics to prevent one case of endophthalmitis. A 500 µg intracameral moxifloxacin at $22 dollars per dose is cost-effective, including for patients with posterior capsular rupture (PCR). SUMMARY: Studies substantiate the safety and efficacy of intracameral antibiotics for endophthalmitis prophylaxis. Intracameral moxifloxacin and cefuroxime are the most common choices. While vancomycin shows potential for efficacy, further studies evaluating clinical outcomes are needed. Adverse events are rare and commonly due to errors in preparation. Topical antibiotics do not provide additional prophylactic benefits to intracameral regimens. Intracameral antibiotics given alone are cost-effective.

Incidence, Clinical Profile, and Management of Keratitis Caused by Uncommon Species of Pseudomonas at a Tertiary Eye Care Center.

PURPOSE: The purpose of this study was to study the incidence, demographic features, clinical course, profiling, and management of uncommon species of Pseudomonas keratitis (other than Pseudomonas aeruginosa ) at a tertiary eye care center. METHODS: Thirty cases of culture-proven uncommon species of Pseudomonas keratitis between January 2017 and December 2021 were retrospectively studied. The incidence, demographic and clinical profile, predisposing factors, microbial results, treatment, and visual outcomes were analyzed. We evaluated the risk factors for poor treatment outcomes. RESULTS: Among bacterial keratitis cases, uncommon species of Pseudomonas keratitis occurred at a rate of 2.2%. The mean age at presentation was 51.37 years, and the most common predisposing factor was corneal trauma (36.7%). The mean best corrected visual acuity (BCVA) [in log of minimum angle of resolution (logMAR)] at presentation was 1.99, and the mean ulcer size was 5.75 mm. On culture, 56.7% of the cases were identified as Pseudomonas putida , 26.7% as Pseudomonas stutzeri , 10% as Pseudomonas mendocina, and 3.3% each of Pseudomonas oryzihabitans and Pseudomonas alcaligenes . We recorded good treatment responses in 66.7% of cases with the medical therapy of a combination of broad-spectrum antibiotics, whereas 33.3% of cases required surgical intervention. The risk factors for poor clinical outcome were older age, ocular trauma, previous ocular surgeries, poor BCVA at presentation, large ulcer size, delayed treatment, hypopyon, and early complications such as perforation, limbal involvement, and total ulcer. CONCLUSIONS: Uncommon species of pseudomonas keratitis was more closely related to predisposing factors such as corneal trauma and other factors such as previous ocular surgeries, older age, large ulcers, longer duration of treatment, early surgical intervention in complicated cases, and poor visual outcome.

Comparative study on costs incurred for treatment of patients with bacterial and fungal keratitis - A retrospective analysis.

Purpose: To compare the costs associated with medications and travel of patients with smear-proven bacterial keratitis and fungal keratitis in a tertiary care center in India. Methods: Retrospective analysis of case records of a cohort of patients who presented between April 2017 and March 2018 to a tertiary care center in India, with infectious keratitis who were smear-positive for bacteria or fungi, and whose costs of treatment and travel were supported by a philanthropic program. Results: In total, 672 case records of 177 smear-positive bacterial keratitis (BK) and 495 smear-positive fungal keratitis (FK) were included in the study. Further, 62% of BK and 75% of FK received more than one antimicrobial drug (P < 0.001). The mean total medication cost (INR) was significantly more in FK (959.1 ± 675.2) compared to BK (674.9 ± 463.7) (P < 0.0001). The mean medication cost (INR) per visit was also more for FK (201.1 ± 109.4) compared to BK (155.2 ± 84.1) (P < 0.0001). The mean total medication cost was significantly more for FK for both patients who healed with medical treatment (611.6 ± 395.6 for BK, 801.5 ± 599.9 for FK, P = 0.0005) and for patients who required TPK (953.7 ± 653.1 for BK, 1374.6 ± 701.5 for FK, P = 0.0023) compared to their respective counterparts in BK. Conclusion: Patients with fungal keratitis incurred significantly more on medications compared to patients with bacterial keratitis irrespective of whether they had healed with successful medical treatment or required therapeutic keratoplasty. Prolonged duration of treatment and the high costs of antifungal medications account for the significant economic burden of fungal keratitis.

Incidence and management of acute endophthalmitis after intravitreal injection of bevacizumab.

PURPOSE: To report the incidence, management, and clinical outcomes of cases who developed acute endophthalmitis following the administering of the intravitreal bevacizumab (IVB) injection. METHODS: In this retrospective, non-comparative, single-center, cross-sectional study, the records of patients diagnosed with acute endophthalmitis following IVB injection between March 2013 and October 2019 were reviewed. Immediate injection of intravitreal antibiotics and early pars plana vitrectomy was performed for all cases after clinical diagnosis of acute post IVB endophthalmitis. RESULTS: A total of 28,085 IVB injections were performed during the study period. Nine eyes of nine patients developed acute post IVB endophthalmitis giving an overall incidence of 0.032% (95% CI, 0.01-0.06) (3.2 in 10,000 injections). Three cases (33%) were culture-positive (staphylococcus epidermidis). The mean time between IVB injection and presentation of endophthalmithis was 2.77 ± 1.25 days (Range, 1-6). The mean number of previously received IVB injections before developing of endophthalmitis was 4 ± 1.5 (range 2 to7). The mean best corrected visual acuity (BCVA) before IVB injection, at the presentation of endophthalmithis and three months after the treatment of endophthalmithis were 1.18 ± 0.62, 2.5 ± 0.42, and 1.94 ± 0.88 logMAR, respectively (P = 0.025). One eye developed phthisis bulbi. CONCLUSION: The incidence of acute endophthalmitis following Intravitreal injection of bevacizumab is very low. The time interval between injection and presentation is short. Prompt treatment with immediate intravitreal antibiotics and early pars plana vitrectomy are key in maximizing outcomes. The prognosis of post-IVB endophthalmitis is poor and may result in significantly visual impairment.

Subpalpebral Antibiotic Lavage as Safe, Emergent, and Cost-Effective Management of Acute Infectious Keratitis Related to Contact Lens Overwear: Case Report and Literature Review.

PURPOSE: The aim of this study is to describe the technique of subpalpebral antibiotic lavage (SAL), which is a highly therapeutic, efficient, and cost-effective method for managing severe bacterial keratitis. METHODS: This case report describes a 26-year-old woman with severe bacterial keratitis in the right eye due to contact lens overwear, with progressive corneal thinning, a hypopyon, impending perforation, and marked visual loss to perception of light despite treatment with intensive topical antibiotics. This was managed with SAL that involves the insertion of a cannula transcutaneously into the upper conjunctival fornix to provide continuous antibiotic irrigation of the ocular surface. RESULTS: By 11 weeks after presentation, the cornea and anterior chamber appeared clinically quiescent, and visual acuity improved to 20/40 corrected in the right eye. CONCLUSIONS: Bacterial keratitis is a potentially blinding condition for which contact lens wear is an important risk factor. Most cases are successfully managed with topical medications; however, in cases of treatment failure, a second-line approach such as SAL can be sight-saving. SAL uses readily available equipment for the delivery of high concentrations of antibiotics to the ocular surface, thus increasing therapeutic efficacy and reducing nursing staff workload. Despite its advantages, the literature reveals apparent underutilization of this technique.

Epidemiology and the Estimated Burden of Microbial Keratitis on the Health Care System in Taiwan: A 14-Year Population-Based Study.

PURPOSE: To investigate the epidemiologic characteristics of microbial keratitis and its overall burden on the health care system in Taiwan. DESIGN: Retrospective, population-based study. METHODS: We conducted a study using claims data in the Taiwan National Health Insurance Research Database in 2000-2013, employing diagnoses, drugs, and procedure codes to define diseases and procedures. Participants were classified into groups according to the requirement of hospitalization and surgical intervention. The main outcome measures were incidence, risk factors, predictive factors for hospitalization and surgical intervention, and health care expenditure. RESULTS: A total of 2,071 patients were included. The overall incidence significantly increased from 8.4 in 2000 to 20.2 per 100,000 person-years in 2013. The peak age range of incidence was between 18 and 40 years, but the peak age group for health care expenditures was those older than 65 years. A total of 704 patients (33.99%) had analyzable risk factors, of which the top 3 were diabetes mellitus (DM, 11.52%), eye trauma (10.55%), and dry eye (8.72%). Older patients, those using steroid and antiglaucoma agents, and those with ocular and systemic diseases were susceptible to further hospitalization and surgical intervention for the treatment of microbial keratitis. CONCLUSIONS: In Taiwan, DM, eye trauma, and dry eye were key predisposing factors for microbial keratitis. Older patients (>40 years) accounted for approximately 80% of health care expenditure for the management of infectious keratitis. Special care may be required for older patients with medication-related risk factors and ocular and systemic comorbidities because they are likely to have severe diseases leading to hospitalization and surgical interventions.

Validation of a Comprehensive Clinical Algorithm for the Assessment and Treatment of Microbial Keratitis.

PURPOSE: To validate a comprehensive clinical algorithm for the assessment and treatment of microbial keratitis (MK). DESIGN: Retrospective cohort study. METHODS: The "1, 2, 3 Rule" for the initial management of MK was conceived by Vital and associates in 2007 to inform the decision as to when to perform corneal cultures. The rule is invoked when any 1 of 3 clinical parameters is met: ≥1+ anterior chamber cells, ≥2 mm infiltrate, or infiltrate ≤3 mm distance from the corneal center. When the rule is met, we added the mandatory use of fortified topical antibiotics after cultures are obtained. We compared outcomes of cases presenting to Massachusetts Eye and Ear 2 years before (Group I, n = 665) and after (Group II, n = 767) algorithm implementation. The primary composite outcome was a vision-threatening complication, such as corneal perforation. RESULTS: At a median follow-up of 67.0 and 60.0 days, respectively, 172 patients experienced a vision-threatening complication (Group I, 12.9% vs Group II, 11.2%, P = .51). While the algorithm codified conventional management practice at either end of disease severity, the effect of algorithm-augmented care was best appreciated in patients with lesions satisfying only 1 criterion. In this group, there was an increase in the proportion of patients undergoing culture at presentation (54.6% vs 67.7%, P = .006), fortified antibiotic prescription (29.7% vs 53.9%, P < .001), and reduction in vision-threatening complications (9.7% vs 1.8%, P = .001). The proportion of patients who were not cultured at presentation but later required culturing decreased (13.4% vs 5.1%, P = .001), as did patients who did not meet any criteria but were nonetheless cultured (23.9% vs 8.5%, P < .001). Multiple logistic regression showed that all algorithm parameters were independently associated with outcome: ≥1+ anterior chamber cells (odds ratio [OR] 1.66, 95% confidence interval 1.09-2.52); ≥2 mm infiltrate (OR 4.74, 2.68-8.40); and ≤3 mm from corneal center (OR 2.82, 1.85-4.31), confirmed with comparison to a bootstrapped sample (n = 10,000). CONCLUSIONS: The implementation of this algorithm reduced vision-threatening complications for patients with lesions satisfying only 1 criterion, arguably the most difficult patients in whom to judge disease severity. Implementation also led to a decrease in patients receiving unnecessary care.

Medication Burden for Patients With Bacterial Keratitis.

PURPOSE: To understand medication use and patient burden for treatment of bacterial keratitis (BK). METHODS: A retrospective study was conducted examining medical records of adult patients with BK in an academic cornea practice. Data collected included medications used in the treatment of BK, dosing of medications, and the number and total duration of clinical encounters. Costs of medications were estimated using the average wholesale pharmacy price. Linear regression analysis was used to investigate associations of medication use with patient demographics and corneal culture results and reported with beta estimates (ß) and 95% confidence intervals (95% CIs). RESULTS: Forty-eight patients with BK (56% female) were studied. Patients were treated for a median of 54 days with 10 visits, 5 unique medications, 587 drops, and 7 prescriptions. The estimated median medication cost was $933 (interquartile range: $457-$1422) US dollars. Positive bacterial growth was significantly associated with more visits (ß: 6.16, 95% CI: 1.75-10.6, P = 0.007), more days of treatment (ß: 86.8, 95% CI: 10.8-163, P = 0.026), more prescribed medications (ß: 2.86, 95% CI: 1.04-4.67, P = 0.003), and more doses of medications (ß: 796, 95% CI: 818-1412, P = 0.012) compared with patients who did not undergo corneal scraping. Patients were prescribed 132 more drops of medication for every 10 years of older age (ß: 132, 95% CI: 18.2-246, P = 0.024). Sex and income were not associated with medication burden or treatment length. CONCLUSIONS: Older patients and those with positive cultures incur the most medication burden in treatment of BK. Providers should be aware of medication usage and cost burden as it may affect compliance with treatment.

Endophthalmitis after intravitreal injections. Incidence, management and prognosis. / Endoftalmitis tras inyecciones intravítreas. Incidencia, manejo y pronóstico.

OBJECTIVE: To assess the rate of endophthalmitis after intravitreal injection (IVI) in a «clean room¼ of a single health centre, following the guidelines of the Spanish Vitreo-Retinal Society (SERV). An analysis was performed on the culture specimens, response to treatment, and final outcomes (guidelines). MATERIAL AND METHODS: A retrospective, observational study was conducted on a consecutive case series of patients diagnosed with infectious endophthalmitis after IVI in a single health centre between 2010 and 2015. Intravitreal and systemic treatment was given following the SERV guidelines. The patients were followed up the case was resolved. RESULTS: There were 5 cases of endophthalmitis out of 9467 IVI (incidence 0.053%). Positive cultures were obtained in aqueous and/or vitreous fluid in all cases, with Staphylococcus epidermidis being involved in 4 out of 5 cases. In 2 cases, final visual acuity was non-light perception due to intractable retinal detachments after resolution of the infectious process. CONCLUSIONS: IVI performed in a «clean room¼ have a low incidence of endophthalmitis. The most common infectious agent was Staphylococcus species. In 2 cases the functional prognosis was poor.

Incidence, management, and visual outcomes in pediatric endophthalmitis following cataract surgery by a single surgeon.

PURPOSE: To report the incidence of endophthalmitis following cataract surgery by a single surgeon in children and to describe its microbiological profile, management, and visual outcomes. METHODS: The medical records of patients who underwent cataract surgery performed by a single surgeon between January 2000 and December 2012 were retrospectively reviewed to identify those with postoperative endophthalmitis. The primary goals of the study were to describe the incidence of endophthalmitis, microbiological profile, and measure visual acuity after management. RESULTS: A total of 2,390 cataract surgeries were performed during the study period. The overall endophthalmitis rate during the study period was 0.376% (95% CI, 0.357-0.395). Of the 9 cases of postoperative endophthalmitis identified, 8 had a median duration of 2.5 days between time of surgery and diagnosis. The common presenting symptoms were pain and redness. Of the 5 cases in which early vitrectomy was performed, 4 showed good visual recovery at final follow-up visit. Both Gram-positive and Gram-negative organisms were seen equally. Culture-positive results were seen in 4 patients, the majority of which showed Acinetobacter calcoaceticus. Most of the organisms were resistant to ceftazidime. CONCLUSIONS: Endophthalmitis following pediatric cataract surgery is rare but occurs rapidly and can cause severe loss of vision. Early recognition and treatment can help in salvaging the vision.

Seasonal Variation in the Incidence of Late-onset Bleb-related Infection After Filtering Surgery in Japan: The Japan Glaucoma Society Survey of Bleb-related Infection Report 3.

PURPOSE: To investigate seasonal variations in the incidence of late-onset bleb-related infection after filtering surgery in Japan and the relationship between season and other factors. PATIENTS AND METHODS: This multicenter, prospective study is part of a 5-year-long Japan Glaucoma Society survey of bleb-related infection. We analyzed 156 cases of first-time infections (106 men, 50 women) encountered over 5 years to determine the seasonal variation using the Roger test and the relationships between season, sex, and age by logistic regression analysis. RESULTS: We noted significant monthly seasonal variation in the incidence of infection, which was the highest in January and February (23 and 18 infections, respectively; P=0.018) and lowest from August to November (9, 9, 11, and 8 infections, in that order). Multiple logistic regression analysis revealed that infections were most frequent among women in spring (odds ratio, 8.43; P=0.005). Staphylococcus aureus and Streptococcus spp. infections were more frequent in warmer seasons than in winter. Less virulent species, namely, coagulase-negative Staphylococcus spp., Corynebacterium spp., and Enterococcus spp., were frequently detected in winter. Coagulase-negative Staphylococcus spp. and Haemophilus influenzae were more frequent in women and men, respectively. CONCLUSIONS: The incidence of late-onset bleb-related infection showed significant seasonal variation and sex differences. The climate in Japan may influence the incidence of bleb-related infection. Moreover, besides climate, physical activity level and lifestyle may contribute to the seasonal variation in the incidence and sex differences in the involved bacterial agents of bleb-related infections in Japan.

[Antibiotic susceptibility patterns of bacteria isolated from keratitis and intraocular infections at Fundación Oftalmológica de Santander (FOSCAL), Floridablanca, Colombia]. / Sensibilidad antibiótica de bacterias obtenidas de queratitis e infecciones intraoculares en la Fundación Oftalmológica de Santander (FOSCAL), Floridablanca, Colombia.

INTRODUCTION: Bacterial resistance is critical for the selection of antibiotics in the treatment of infections, so it is vital to know its current status in our geographical area. OBJECTIVE: To determine in vitro antibiotic susceptibility of bacterial isolates obtained from keratitis and intraocular infections. MATERIALS AND METHODS: A retrospective study of microbiological tests in Fundación Oftalmológica de Santander (FOSCAL) was carried out between June, 2011, and January, 2012. RESULTS: A total of 92 samples were examined and 110 bacteria, 27 fungi and 12 free-living amoebae were identified. Polymicrobial infections constituted 50% of the total; 1.1%, 0%, 1.1%, 16.9%, 29.3% and 85% of Gram-positive bacteria were resistant to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, respectively, while 0%, 8.3%, 0%, 0%, 18.2% and 27.3% of Gram-negative bacteria were resistant to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, respectively. For methicillin-resistant coagulase-positive staphylococci, resistance percentages to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin were 0%, 0%, 0%, 7%, 17% and 100%, respectively. For methicillin-resistant coagulase-negative staphylococci, resistance percentages to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin were 3%, 0%, 0%, 24%, 44% and 100%, respectively. Overall bacterial resistance to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, for both Gram-positive and Gram-negative, was 1%, 1%, 1%, 15.1%, 28% and 64.5%, respectively. CONCLUSIONS: The levels of bacterial resistance to imipenem, moxifloxacin and gatifloxacin were lower than for levofloxacin, ciprofloxacin and tobramycin. The levels of resistance to tobramycin were very high, which calls into question its usefulness in this region of our country.

Orbital cellulitis in Scotland: current incidence, aetiology, management and outcomes.

PURPOSE: Orbital cellulitis is a potentially blinding and life-threatening condition. There are little published data on the incidence of orbital cellulitis and little is known about the differences between children and adults affected. The purpose of this study was to identify the incidence, aetiology, management and outcome of orbital cellulitis in children and adults in Scotland. METHODS: This study was a 1-year prospective observational study using the Scottish Ophthalmic Surveillance Unit reporting system among Scottish ophthalmologists. RESULTS: The response rate from ophthalmologists was 66.4%. There were 15 children and 5 adults reported giving an incidence of 1.6 per 100 000 and 0.1 per 100 000 in children and adults, respectively. 47% of children had a preceding upper respiratory tract infection with 87% having radiological evidence of sinus disease. Within the adult group, there was preceding immunosuppression and trauma. Streptococcus (66%) and Haemophilus (46%) species were the most commonly isolated pathogens in children. Respiratory pathogens were less predictable in adults. All patients were treated with intravenous antibiotics. All children with orbital and subperiosteal abscesses had surgery; one adult with orbital abscess did not have surgery. There were two cases of series morbidity: one intracranial spread of infection and one evisceration. DISCUSSION: The incidence of orbital cellulitis is higher in children than in adults. In children, it commonly follows upper respiratory infection and sinus disease; however, in adults, preceding illness and trauma are more common. Respiratory pathogens are common in affected children. Intravenous antibiotics and surgical treatment of abscesses remain the preferred management.

Sensibilidad antibiótica de bacterias obtenidas de queratitis e infecciones intraoculares en la Fundación Oftalmológica de Santander (FOSCAL), Floridablanca, Colombia / Antibiotic susceptibility patterns of bacteria isolated from keratitis and intraocular infections at Fundación Oftalmológica de Santander (FOSCAL), Floridablanca, Colombia

Introducción. La resistencia bacteriana es crítica para la selección de los antibióticos en el tratamiento de las infecciones, por ello es vital conocer su estado actual en nuestro medio. Objetivo. Determinar la sensibilidad antibiótica bacteriana in vitro obtenida de los cultivos de queratitis e infecciones intraoculares. Materiales y métodos. Se llevó a cabo un estudio retrospectivo en la Fundación Oftalmológica de Santander (FOSCAL), entre junio de 2011 y enero de 2012. Resultados. Se examinaron 92 muestras. Se identificaron 110 bacterias, 27 hongos y 12 amebas de vida libre. Del total de bacterias Gram positivas, 1,1 %, 0 %, 1,1 %, 16,9 %, 29,3 % y 85 % fue resistente a imipenem, moxifloxacina, gatifloxacina, levofloxacina, ciprofloxacina y tobramicina, respectivamente, mientras que la resistencia a estos mismos fármacos se presentó, respectivamente, en 0 %, 8,3 %, 0 %, 0 %, 18,2 % y 27,3 % de las bacterias Gram negativas. Los porcentajes de resistencia de los estafilococos positivos para coagulasa resistentes a la meticilina fueron 0 %, 0 %, 0 %, 7 %, 17 % y 100 %, respectivamente, y los porcentajes de los estafilococos negativos para coagulasa resistentes a la meticilina fueron 3 %, 0 %, 0 %, 24 %, 44 % y 100 %, respectivamente. Los porcentajes de resistencia bacteriana globales (tanto para bacterias Gram positivas como para Gram negativas) a imipenem, moxifloxacina, gatifloxacina, levofloxacina, ciprofloxacina y tobramicina fueron 1 %, 1 %, 1 %, 15,1 %, 28 % y 64,5 %, respectivamente. Conclusiones. Los niveles de resistencia bacteriana para imipenem, moxifloxacina y gatifloxacina fueron menores que para levofloxacina, ciprofloxacina y tobramicina. Los niveles de resistencia para la tobramicina fueron muy altos, lo que pone en duda su utilidad clínica en las infecciones oculares en nuestro medio.

Introduction: Bacterial resistance is critical for the selection of antibiotics in the treatment of infections, so it is vital to know its current status in our geographical area. Objective: To determine in vitro antibiotic susceptibility of bacterial isolates obtained from keratitis and intraocular infections. Materials and methods: A retrospective study of microbiological tests in Fundación Oftalmológica de Santander (FOSCAL) was carried out between June, 2011, and January, 2012. Results: A total of 92 samples were examined and 110 bacteria, 27 fungi and 12 free-living amoebae were identified. Polymicrobial infections constituted 50% of the total; 1.1%, 0%, 1.1%, 16.9%, 29.3% and 85% of Gram-positive bacteria were resistant to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, respectively, while 0%, 8.3%, 0%, 0%, 18.2% and 27.3% of Gram-negative bacteria were resistant to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, respectively. For methicillin-resistant coagulase-positive staphylococci, resistance percentages to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin were 0%, 0%, 0%, 7%, 17% and 100%, respectively. For methicillin-resistant coagulase-negative staphylococci, resistance percentages to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin were 3%, 0%, 0%, 24%, 44% and 100%, respectively. Overall bacterial resistance to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, for both Gram-positive and Gram-negative, was 1%, 1%, 1%, 15.1%, 28% and 64.5%, respectively. Conclusions: The levels of bacterial resistance to imipenem, moxifloxacin and gatifloxacin were lower than for levofloxacin, ciprofloxacin and tobramycin. The levels of resistance to tobramycin were very high, which calls into question its usefulness in this region of our country.

Ophthalmic methicillin-resistant Staphylococcus aureus infections: sensitivity and resistance profiles of 234 isolates.

To identify the sensitivity and resistance profiles of ophthalmic Methicillin-resistant Staphylococcus aureus (MRSA) in a large, diverse demographic. The electronic database of a large health maintenance organization was searched for patients who had an ophthalmic bacterial culture performed from 2002 to 2008 which grew MRSA. Data collected included culture source, sensitivity and resistance profiles, and whether the infection was community or nosocomially-acquired. In this retrospective study, not all isolates were tested for all the antibiotics. All isolates tested for vancomycin, trimethoprim/sulfamethoxazole, and rifampin were sensitive to these antibiotics and none were resistant. Gentamycin and chloramphenicol had the next highest sensitivity to resistance ratios, followed by tetracycline and trimethoprim (without sulfamethoxazole). Community acquired MRSA is becoming more frequent and the most common ophthalmic manifestation is eyelid involvement. The sensitivities to antibiotics of the ophthalmic MRSA isolates in this study are consistent with that seen in the literature.

Assessment of polymerase chain reaction in the detection of pseudomonas aeruginosa in contact lens-induced severe infectious keratitis.

PURPOSE: The aim of this study is to evaluate the role of real-time polymerase chain reaction (PCR) and conventional bacterial culture methods in the detection of Pseudomonas aeruginosa in contact lens-induced severe, partially treated corneal ulcers referred to a tertiary center. METHODS: The study duration was 6 months. All patients with contact lens-related corneal ulcer, requiring admission during the study period were recruited. Samples from corneal scrapings were simultaneously sent at the time of admission for PCR and culture testing. An in-house real-time PCR was developed to detect the P. aeruginosa lasA gene. The results of PCR and culture were compared using McNemar's chi2 test. RESULTS: Ten patients were recruited. The mean age was 33 years (20-45 years). All the patients had contact lens-related keratitis (>4 mm) of which eight (80%) were found positive for P. aeruginosa by PCR or culture. There was no significant difference between PCR and culture in detecting P. aeruginosa (P<0.05). CONCLUSIONS: PCR is, at least, as good as conventional cultures in detecting P. aeruginosa. It is a rapid assay as compared with culture, and early detection enables prompt treatment thus reducing the destructive effect of the organism on the cornea.

Assessment of the use of anterior segment optical coherence tomography in microbial keratitis.

PURPOSE: To investigate the imaging capabilities of anterior segment optical coherence tomography (AS OCT) in microbial keratitis and to assess whether measurements of the quantitative parameters, infiltrate thickness and corneal thickness, were possible. DESIGN: Prospective, noncomparative, observational case series. METHODS: The study was conducted at a university hospital clinical setting. Seven patients (eyes) with suspected microbial keratitis underwent standard clinical examination and treatment based on slit-lamp clinical findings. AS OCT scanning was performed on presentation and at two follow-up appointments. All scans were carried out with the scanning beam passing through the center of the infiltration and at a specific meridian. Examination was carried out by the same operator. RESULTS: Corneal infiltration was imaged as a hyperreflective area in the corneal stroma on high-resolution AS OCT scans. Retrocorneal pathologic features and anterior chamber inflammatory cells could be imaged. Corneal and infiltrate thickness could be measured with calipers in six cases. In one case, corneal and infiltrate thickness could not be measured because of a thick inflammatory plaque attached to the endothelium. In this case, the width of the plaque was measured on serial scans. CONCLUSIONS: AS OCT imaging provides a range of parameters that can be used to assess microbial keratitis and the treatment response objectively.