Hookworm infestation as a risk factor for Mooren's ulcer in South India.

OBJECTIVE: To investigate the association between Mooren's ulcer and intestinal hookworm infestation in South India. DESIGN: Prospective observational case-control study. PARTICIPANTS: Fifteen patients with Mooren's ulcer and 30 age- and gender-matched controls seen at Aravind Eye Hospital. METHODS: Stool samples from the Mooren's ulcer patients and controls were collected and analyzed for presence of hookworm infestation. MAIN OUTCOME MEASURE: Prevalence of hookworm infestation in Mooren's ulcer patients and controls. RESULTS: There was a statistically significant correlation between intestinal hookworm infestation and the occurrence of Mooren's ulcer (P = 0.009). Retrospective exploratory subgroup analyses suggested that the correlation between intestinal hookworm infestation and the occurrence of Mooren's ulcer in men (P<0.0001) was stronger than the correlation in women, with no statistically significant difference being observed in the prevalence of hookworm infestation between women with Mooren's ulcer and female control subjects (P>0.99). Similarly, when both the Mooren's ulcer and the control subject groups were analyzed retrospectively by age > 50 years or age < 50, subjects with an age over 50 demonstrated a stronger correlation between hookworm infestation and Mooren's ulcer than controls (P = 0.017), whereas there was no statistically significant difference in the prevalence of hookworm infection between Mooren's ulcer subjects and control subjects < or = 50 (P = 0.31). CONCLUSION: Intestinal hookworm infestation appears to be associated with the development of Mooren's ulcer in South India. Although the power of our retrospective exploratory subgroup analyses was limited by multiple testing and small sample sizes, these data suggest further that the correlation between intestinal hookworm infestation and the development of Mooren's ulcer may be greatest in male patients with more advanced age.

Clinical characteristics of Mooren's ulcer in South India.

AIM: To describe the clinical characteristics at presentation of a large cohort of patients with Mooren's ulcer in South India. METHODS: The medical records of patients with Mooren's ulcer examined in the cornea clinic at Aravind Eye Hospital Madurai, Tamil Nadu, India, over a 10-year period were reviewed in this retrospective observational case series. RESULTS: The cohort contained 242 eyes of 166 patients. All patients were from South India, and men outnumbered women by a ratio of 4.7:1. The median and mean ages at presentation were 65 and 61 years, respectively, with a range of 13-95 years. One eye was affected in 90 of 166 (54%) patients. Visual acuity in the affected eye at presentation ranged from 6/6 to light perception, and was 6/12 or better in 34 of 242 (14%) eyes, between 6/12 and 3/60 in 168 (69%) eyes, and worse than 3/60 in 40 (17%) eyes. Partial peripheral corneal ulceration was observed in 222 (92%) eyes, complete peripheral corneal ulceration was observed in 15 (6%) eyes and total corneal ulceration was observed in 5 (2%) eyes. For those 222 eyes with partial peripheral ulceration, 152 (68%) showed temporal involvement, 129 (58%) showed nasal involvement, 116 (52%) showed inferior involvement and 30 (14%) showed superior involvement. Perforation was observed in 26 (11%) eyes, and was more common in eyes with peripheral as compared with total ulceration (p<0.001). Identified risk factors in the cohort included evidence of prior corneal surgery (22%), corneal trauma (17%) and corneal infection (2%). CONCLUSIONS: Mooren's ulcer is a rare and potentially blinding eye condition observed not infrequently in the cornea clinic at Aravind Eye Hospital. Men are affected more often than women and may present with either unilateral or bilateral disease. Perforation is observed in approximately 1 in 10 affected eyes at presentation and occurs most often in the setting of peripheral ulceration. The occurrence of prior corneal surgery, trauma or infection in nearly one third of patients supports theories of exposure to corneal antigen in the pathogenesis of this disorder.

Economic analysis of corneal ulcers in South India.

PURPOSE: To estimate the costs of treating corneal ulcers at a tertiary eye care center in south India from a patient perspective. METHODS: A prospective cohort study design at a tertiary eye care center in south India. Each subject presenting with corneal ulcers to the center had a detailed clinical and laboratory workup including slit-lamp biomicroscopy, direct smear examination with appropriate stains, and cultures. Data on direct costs including costs of consultation, studies to confirm diagnosis, and treatment were collected at baseline and follow-up visits. We also collected indirect costs including travel, accommodation, food, and loss of wages of both the subject and accompanying persons. RESULTS: We recruited 498 consecutive cases for the study. The mean duration of onset of symptoms before presentation at the cornea service was 13.1 +/- 19.9 days. The mean follow-up duration was 34.8 +/- 28.2 days. The total overall cost for accessing and receiving care was 85.8 US dollars +/- 4.6 (95% confidence interval: 76.4 US dollars, 94.6). The mean total cost to diagnose and appropriately treat 1 case of keratitis such that the patient had vision better than 6/18 at final follow-up was 56.2 US dollars +/- 3.6 (95% confidence interval: 49.0 US dollars, 63.3). CONCLUSIONS: : The costs to the patient to receive appropriate care for corneal ulcers in this population are much higher than the average monthly wage for this population. There is an urgent need to devise strategies that may help reduce costs of care for corneal ulcers in this population.

Nocardia keratitis: species, drug sensitivities, and clinical correlation.

PURPOSE: To correlate the clinical presentation and treatment outcome of Nocardia keratitis with the time to diagnosis, different species and with the drug sensitivity pattern. METHOD: Patients with Nocardia corneal ulcers were studied at a tertiary eye care center. Speciation of Nocardia isolates was done by sequencing the 16s rRNA gene. Clinical response to treatment was assessed by chart review. RESULTS: Twenty one (65.3%) patients presented within 15 days of the onset of symptoms with typical clinical features of Nocardia keratitis, ie, a ring-like distribution of superficial infiltrates in a wreath pattern. Eight patients (25%) who presented after 15 days and within 30 days had an ulcer resembling fungal keratitis. N. Cyriacigeorgica (n = 11; 34.37%), N. asteroides (n = 9; 28%), N. farcinica (n = 7; 22%,) and N. Otitidiscaviarum (n = 5; 16%). All the species had 100% sensitivity to amikacin, sulphamethoxazole, imipenem and co-trimoxazole. Time to diagnosis of the infection was significantly associated with the different types of clinical presentation; those presenting early having the typical clinical picture (P = 0.004). Patients (73%) presenting within 15 days showed a highest recovery rate. (P = 0.045). The recovery time of the patients when compared with species showed those who were infected with N. cyriageorgica had a healing time of less than 15 days. Clinically, healing was faster when treated with 2% amikacin. Visual outcome improved in fourteen patients (44%) and sixteen (50%) patients remained the same (P = 0.0001). CONCLUSION: Characteristic clinical picture of Nocardia is dependant on early presentation. It could be mistaken for fungal keratitis. Microbiological confirmation is important. Drug of choice for Nocardia keratitis is amikacin.

Risk factors for treatment outcome in fungal keratitis.

PURPOSE: To identify risk factors at diagnosis that can serve as prognostic indicators of primary treatment failure in cases of fungal keratitis. DESIGN: Prospective, nonrandomized, interventional, comparative study. PARTICIPANTS: A total of 115 consecutive patients with fungal keratitis treated at one center during a 6-month period. METHODS: Patients with a microscopic corneal ulcer smear that was positive for fungus were enrolled and treated with 5% natamycin monotherapy according to the protocol of the hospital. Treatment responses were assessed at the end of 4 weeks. The prognostic indicators were used in a Poisson model for multiple regression analysis to estimate the relative risk of the main prognostic variables. MAIN OUTCOME MEASURES: Response of the ulcer to treatment. RESULTS: Of the 115 patients analyzed in the study, 52 (45.2%) were treatment successes, 27 (23.5%) had slow-healing ulcers, and 36 (31.3%) were refractory to primary treatment. Multivariate analysis showed that the predictors of treatment failure were ulcers that exceeded 14 mm(2) (P = 0.009), the presence of hypopyon (P = 0.003), and identification of Aspergillus (P = 0.003). CONCLUSION: In patients with fungal keratitis treated with 5% natamycin monotherapy, larger ulcer size and infection with Aspergillus were predictors of a poor outcome.

Rhodococcus ruber as a cause of keratitis.

PURPOSE: To report a case of suppurative keratitis caused by Rhodococcus ruber in a healthy 31-year-old male patient. METHODS: Ocular examination of the patient revealed a central corneal epithelial defect following trauma, with severe anterior chamber reaction hypopyon. Corneal scrapings were performed from the base of the ulcer and were subjected to routine microbiologic investigation including direct microscopic techniques (Gram stain and 10% KOH), and culture was done on blood agar and potato dextrose agar. Biochemical analysis and antibiotic sensitivity testing were done on the isolate, and additional confirmation was done by DNA sequencing. RESULTS: The isolate was identified as Rhodococcus ruber, an uncommon cause of suppurative keratitis. The isolate was found to be sensitive to augmentin, erythromycin, co-trimoxazole, tobramycin, amikacin, ciprofloxacin, ofloxacin, and sulfamethoxazole. CONCLUSION: We present a case of Rhodococcus ruber, which was successfully treated. Even if the clinical picture of ulcer is nonspecific, the need of a routine microbiologic examination and sequencing proves to be confirmatory in cases of suppurative keratitis, where the causative organisms are varied in nature.

Herpes simplex keratitis and visual impairment: a case series.

PURPOSE: To record the natural history of herpes simplex keratitis and estimate visual impairment in eyes of patients diagnosed with herpes simplex keratitis. MATERIALS: This was a retrospective, descriptive case study for five years of the eyes of patients with clinically diagnosed herpes simplex keratitis. These patients had presented to the cornea services and a cornea specialist carried out the ocular examination under slit-lamp magnification. The medical records were reviewed by the authors. Visual acuity at presentation and clinical details on examination were recorded and, diagnosis of the stage of disease given in the case record was noted. Statistical analysis was done using chi-square-test and Fisher exact test. RESULTS: Of a total of 212 patients (220 eyes), there were 144 males and 68 females; 118 eyes presented with stromal lesions, 44 eyes with epithelial lesions, 39 eyes with epithelial and stromal lesions and 19 eyes with endothelitis. The improvement in visual acuity to more than 20/40 in the four clinical groups was 23 out of 44 eyes with epithelial lesion (52.27%), 83 out of the 118 eyes with stromal lesions (70.33%), 23 out of 39 eyes with epithelial and stromal lesions (58.97%) and 8 out of the 19 eyes with endothelitis (42.10%). The mean improvement in visual acuity was 3.44 lines (SD +/- 4.06). CONCLUSION: Most patients had mild disease. The majority of the patients attained the final visual acuity of 6/12 or better in the affected eye. Thus, there was only a temporary visual morbidity with fairly good functional visual outcome in majority of the patients.

Postcataract endophthalmitis in South India incidence and outcome.

OBJECTIVE: To determine the incidence of acute-onset postcataract endophthalmitis, identify risk factors, and determine clinical outcomes in a tertiary eye care center in South India. DESIGN: Retrospective, interventional, observational case series. PARTICIPANTS: All patients who underwent cataract extraction from January 2002 to December 2003 at Aravind Eye Hospital, Madurai. METHODS: The records of patients with acute endophthalmitis after cataract surgery were reviewed. MAIN OUTCOME MEASURES: Acute-onset postcataract endophthalmitis, incidence rates, risk factors, organisms cultured, and visual acuity outcomes after treatment. RESULTS: During the study period, 36072 cataract surgeries were performed; these included 22294 cases of phacoemulsification and 9503 cases of extracapsular cataract extraction. A total of 19 eyes developed acute endophthalmitis after cataract surgery (average 2-year incidence, 0.05%). Ten cases were culture positive (average 2-year incidence, 0.03%). In multivariate analysis, increased risk of endophthalmitis was associated with intraoperative complications, such as posterior capsular rent and vitreous loss (relative risk [RR], 6.57; 95% confidence interval [CI], 1.5-28.5; P = 0.05) for all endophthalmitis cases, age >60 years for culture-positive endophthalmitis cases (RR, 6; 95% CI, 0.7-47.8; P = 0.04), and an extracapsular cataract extraction technique for culture-positive endophthalmitis cases (RR, 4.9; 95% CI, 1.2-19.3; P = 0.001). After follow-up of 37 days, 5 (29.41%) of the 17 patients achieved a best-corrected visual acuity (BCVA) of 20/40, and the remaining 7 (32.3%) had a BCVA better than 20/200. Of the culture-positive cases, Nocardia species was the most common organism isolated, accounting for more than half of these cases (6/10 [60%]). CONCLUSIONS: This study found the incidence of acute postoperative endophthalmitis after cataract surgery to be 0.05%. Extracapsular cataract extraction technique and the occurrence of intraoperative complications are major risk factors for developing endophthalmitis. Visual outcome after endophthalmitis was generally poor. Nocardia is a lesser-known but virulent organism causing endophthalmitis, the management of which still poses a therapeutic dilemma.

Reliability of transport medium in the laboratory evaluation of corneal ulcers.

PURPOSE: To compare the microbiological yield of corneal ulcer cultures established by direct inoculation of culture media vs indirect inoculation by means of transport medium (Amies without charcoal). DESIGN: Single masked, prospective clinical trial. METHODS: Scrapings were obtained for Gram and potassium hydroxide (KOH) stains from eyes with presumed infectious keratitis and cultured by direct plating onto standard media. Samples were also held in transport media (Amies without charcoal) at room temperature and then plated after 4 and 24 hours. Yields from direct plating vs cultures by means of transport media were compared. RESULTS: Of 100 consecutive eyes examined with presumed infectious keratitis, Gram or KOH stain revealed a bacterial or fungal agent in 69 cases (69%). Of these, 26 were bacterial and 43 fungal. Twenty-two bacterial infections produced positive cultures by direct plating, and all produced the same organism with Amies medium after 4 and 24 hours, respectively. For 43 fungal infections identified by KOH stain, 29 (67%) yielded a positive result after 4 hours in Amies transport medium and 27 (63%) after 24 hours in Amies medium. A total of three cases (7%) that showed fungal infection on KOH stain but did not yield organisms by direct plating did so after inoculation with Amies transport medium. For all comparisons, there was no difference in recovery rates by means of transport medium compared with direct plating (McNemar exact P > .05). CONCLUSIONS: In the clinical setting, Amies transport medium may be a useful alternative to direct inoculation onto blood agar for the laboratory evaluation of infectious keratitis.

Absence of phenotype-genotype correlation of patients expressing mutations in the SLC4A11 gene.

PURPOSE: The purposes of this study were to describe the clinical characteristics of corneal patients with mutations in the SLC4A11 gene and to determine if these characteristics could be correlated with specific genetic mutations. METHODS: A retrospective case series review was conducted. Baseline demographic data, including gender, age at diagnosis of congenital hereditary endothelial dystrophy, family history, and pedigree information, were obtained. Information from clinical examination, including intraocular pressure, ultrasonic pachymetry, best spectacle-corrected visual acuity, axial length, and slit-lamp biomicroscopic evaluation, including corneal diameter and fundus examination, were also documented from the notes. History of corneal surgery was also recorded. Hearing loss was assessed by audiometry. Genetic analysis was performed by polymerase chain reaction amplification and sequencing. RESULTS: Seven patients were identified. Four of the seven had associated hearing loss; all of the patients had undergone or were awaiting penetrating keratoplasty to one or both eyes. No correlation could be reached between the ocular phenotype and the gene mutation in this small sample. Individuals with the same mutation had different degrees of hearing loss within their respective families. CONCLUSIONS: Corneal endothelial cells are more vulnerable to defects in the functional activity of SLC4A11 than cells of the striae vascularis of the inner ear. Both congenital hereditary endothelial dystrophy 2 and Harboyan syndrome have similar ocular phenotypes, ie, diffuse bilateral corneal edema present at birth or within the neonatal period; hence, audiometry must be performed to differentiate the two conditions.

Non-contact lens related Acanthamoeba keratitis at a tertiary eye care center in south India: Implications for eye care programs in the region.

BACKGROUND: The purpose of our research was to determine diagnosis and outcomes for non-contact lens related Acanthamoeba keratitis in south India. MATERIAL/METHODS: A retrospective review of the medical and microbiology records of culture-positive Acanthamoeba cases presenting between 1987 and 2001 to a tertiary eye care center in south India. RESULTS: One hundred and three culture-positive cases of Acanthamoeba were identified during chart review. The majority of these cases (70.9%) were already on treatment for keratitis with antibiotics, antifungal and antiviral regimes prior to our examination; 45.2% were on different combinations of regimes. Cysts could be identified using 10% KOH mount in 83.5% of these cases. Clinical resolution with medical therapy was achieved for 83.5% of the cases; the median duration of treatment was 90.5 days. Outcomes - either clinical or visual - did not differ between CONCLUSIONS: Acanthamoeba keratitis cases presenting to this tertiary care center were non-contact lens wearers, and already on empirical treatment for either bacterial or fungal keratitis. A basic lab facility including only microscopy and smear examinations may aid etiological diagnosis of corneal ulcers, and reduce the current practice of using combinations of treatment regimes on an empirical basis.