Sarita Kar

Diagnosis and treatment outcome of mycotic keratitis at a tertiary eye care center in eastern India.

BackgroundMycotic keratitis is an important cause of corneal blindness world over including India. Geographical location and climate are known to influence the profile of fungal diseases. While there are several reports on mycotic keratitis from southern India, comprehensive clinico-microbiological reports from eastern India are few. The reported prevalence of mycotic keratitis are 36.7%,36.3%,25.6%,7.3% in southern, western, north- eastern and northern India respectively. This study reports the epidemiological characteristics, microbiological diagnosis and treatment outcome of mycotic keratitis at a tertiary eye care center in eastern India.MethodsA retrospective review of medical and microbiology records was done for all patients with laboratory proven fungal keratitis.ResultsBetween July 2006 and December 2009, 997 patients were clinically diagnosed as microbial keratitis. While no organisms were found in 25.4% (253/997) corneal samples, 23.4% (233/997) were bacterial, 26.4% (264/997) were fungal (45 cases mixed with bacteria), 1.4% (14/997) were Acanthamoeba with or without bacteria and 23.4% (233/997) were microsporidial with or without bacteria. Two hundred fifteen of 264 (81.4%, 215/264) samples grew fungus in culture while 49 corneal scrapings were positive for fungal elements only in direct microscopy. Clinical diagnosis of fungal keratitis was made in 186 of 264 (70.5%) cases. The microscopic detection of fungal elements was achieved by 10% potassium hydroxide with 0.1% calcoflour white stain in 94.8%(238/251) cases. Aspergillus species (27.9%, 60/215) and Fusarium species (23.2%, 50/215) were the major fungal isolates. Concomitant bacterial infection was seen in 45 (17.1%, 45/264) cases of mycotic keratitis. Clinical outcome of healed scar was achieved in 94 (35.6%, 94/264) cases. Fifty two patients (19.7%, 52/264) required therapeutic PK, 9 (3.4%, 9/264) went for evisceration, 18.9% (50/264) received glue application with bandage contact lens (BCL) for impending perforation, 6.1% (16/264) were unchanged and 16.3% (43/264) were lost to follow up. Poor prognosis like PK (40/52, 75.9%, p < 0.001) and BCL (30/50, 60%, p < 0.001) was seen in significantly larger number of patients with late presentation (> 10 days).ConclusionsThe relative prevalence of mycotic keratitis in eastern India is lower than southern, western and north-eastern India but higher than northern India, however, Aspergillus and Fusarium are the predominant genera associated with fungal keratitis across India. The response to medical treatment is poor in patients with late presentation.

Staphylococcus aureus eye infections in two Indian hospitals: emergence of ST772 as a major clone

Purpose The purpose of this study was to perform molecular characterization of Staphylococcus aureus isolates causing a variety of eye infections from two major eye care hospitals in India. Methods Twenty-four isolates from Aravind Eye Hospital, Madurai, India, and nine isolates from LV Prasad Eye Institute, Bhubaneswar, India, representing severe to nonsevere eye infections like microbial keratitis to lacrimal sac abscess, were characterized. Staphylococcal cassette chromosome mec typing, multilocus sequence typing, accessory gene regulator typing, staphylococcal protein A typing, and pulsed field gel electrophoresis were used, along with determination of the presence of Panton–Valentine leucocidin toxin and endotoxin gene cluster among each sequence type. Results The majority of eye infections, both severe and nonsevere, were caused by sequence type (ST)772, positive for the Panton–Valentine leucocidin gene, and carrying methicillin-resistant staphylococcal cassette chromosome mec type V cassette (22/33, 67%). Some of the other sequence types that caused severe eye infections were ST1 (9%), 5 (3%), 72 (6%), 88 (3%), 121 (3%), and 672 (3%). This is the first report of the presence of ST1 and 88 in India. Conclusion Although the number of isolates included in this study was small, most of the eye infections were caused by community-associated S. aureus where patients had no history of hospitalization or treatment in the past year. In the case of six severe infections, patients were admitted for surgeries and there is probability of hospital infection. In addition, only methicillin-resistant S. aureus isolates carrying staphylococcal cassette chromosome mec type V were detected. Epidemic methicillin-resistant Staphylococcus aureus 15 (ST22) is a major ST found in health care as well as community settings in non-eye infections in India, but only one methicillin-sensitive S. aureus isolate belonging to ST22 was detected. Predominantly ST772, along with a few other STs, caused the 33 eye infections studied.

Clinical Trial of 0.02% Polyhexamethylene Biguanide Versus Placebo in the Treatment of Microsporidial Keratoconjunctivitis

PURPOSE To evaluate the efficacy of 0.02% polyhexamethylene biguanide (PHMB) in the treatment of keratoconjunctivitis caused by microsporidia. DESIGN Prospective, double-masked, randomized, placebo-controlled clinical trial. METHODS One hundred forty-five patients in a single-center, institutional setting were recruited. Patients with superficial keratoconjunctivitis and corneal scrapings with positive results for microsporidial spores were included. Patients with any known allergy to PHMB, and clinically suspected bacterial, viral, or fungal infection were excluded from the study. One hundred forty-five patients were treated at 4-hour intervals with either topical 0.02% PHMB (n = 72) or placebo (n = 73). The patients were followed-up on day 3 +/- 1, day 7 +/- 1, and weekly thereafter, until complete resolution of the corneal lesions. Patients with deterioration of clinical symptoms and signs were removed from the study and were treated with PHMB. Main outcome measures included resolution time, cure time, and final visual outcome. RESULTS Resolution time was defined as the amount of time until disappearance of corneal epithelial infiltrates. Cure time was defined as the interval until absence of conjunctival congestion, corneal epithelial lesion, and superficial punctate keratitis. Baseline characteristics showed no relevant difference between the groups. The mean resolution time was 4.9 +/- 2.2 days and 4.6 +/- 2.3 days in the PHMB and placebo groups, respectively (P = .49). The mean time for cure was 13.5 +/- 6.6 days and 9.4 +/- 5.1 days in PHMB and placebo groups, respectively (P = .004). There was no significant difference in the final visual outcome between the groups (P = .10). No serious adverse effects were noted. CONCLUSIONS Treatment of microsporidial keratoconjunctivitis with PHMB does not offer any significant advantage over placebo, suggesting self-limiting nature of the disease.

Diagnosis, clinical features and treatment outcome of microsporidial keratoconjunctivitis

Aim To report the clinical and microbiological profile of patients with microsporidial keratoconjunctivitis in a tertiary eye care centre in India. Methods A retrospective analysis of medical records of all cases of microbiologically confirmed microsporidial keratoconjunctivitis, who presented between March 2007 and October 2010, was done. In a single-centre, institutional setting, 278 eyes of 277 apparently healthy patients were analysed. Results The mean age was 36±14 years (range 6–80). The mean duration of symptoms was 7.7±6.2 days (range 1–60). Keratic precipitates were present in 20.1% patients. A superficial scar was present in 39.2% patients. Majority (26.6%) of the patients reported in the month of August. Microscopic examination of corneal scraping, using potassium hydroxide with calcofluor white and Gram stain, demonstrated microsporidial spores in 98.9% and 89.7% cases, respectively. Patients received either topical 0.02% polyhexamethylene biguanide or lubricants. The mean time for resolution was 6.0±2.9 days (range 2–18). Final visual acuity was ≥20/30 in 75.1% cases. Conclusions Microsporidial keratoconjunctivitis is common in India. It is seasonal, can occur in healthy individuals and can be diagnosed using simple microbiological methods. Treatment outcome is generally satisfactory.

Is inclusion of Sabouraud dextrose agar essential for the laboratory diagnosis of fungal keratitis

Purpose: To determine whether the inclusion of Sabouraud dextrose agar (SDA) is essential in the diagnosis of fungal keratitis. Materials and Methods: Corneal scrapings of 141 patients with microbial keratitis were smeared and cultured. Sheep blood agar (BA), chocolate agar (CA), SDA, non-nutrient agar (NNA) with Escherichia coli overlay, and brain heart infusion broth (BHI) were evaluated for time taken for growth and cost. The media were also evaluated experimentally for rate of growth and time taken for identification. Results: Twenty-six of 39 patients positive for fungus in corneal scrapings by microscopy were culture-positive. Fungus grew on BA in 22/39, on CA in 18/39, on SDA in 17/39, on NNA in 17/39, and on BHI in 13/39 cases. Growth on SDA was higher in ulcers with larger infiltrate (6/18 versus 9/13, P = 0.04). Estimated saving with inclusion of only BA/CA was Rs. 600 per patient. Performance of all media was similar in in vitro experiment although the characteristic spores and color were seen earlier on SDA. Conclusion: Fungal keratitis can be reliably confirmed on BA or CA, which support growth of both bacteria and fungus.

Fungal periorbital necrotizing fasciitis in an immunocompetent adult.

A 55-year-old man presented with profound swelling of the upper face and fever with a history of preceding insect bite. He was nonalcoholic and immunocompetent. Orbital CT showed a predominantly preseptal soft-tissue swelling. Empiric treatment with broad-spectrum antibiotics resulted in partial response. Surgical debridement and microbiologic evaluation of the necrotic tissue were performed. Gram stain showed budding yeast cells. Candida and Aspergillus spp. grew in culture after 48 hours. The patient received oral fluconazole, 200 mg once a day for 8 weeks. Complete resolution was documented at 16 weeks. In tropical regions, Candida and Aspergillus spp. may cause periorbital necrotizing fasciitis in immunocompetent adults.

DNA chip-assisted diagnosis of a previously unknown etiology of intermediate uveitis- Toxoplasma gondii

We report the use of DNA chip technology in the identification of Toxoplasma gondii as the etiological agent in two patients with recurrent intermediate uveitis (IU). Both patients had recurrent episodes of vitritis (with no focal retinochoroidal lesion) over varying time intervals and were diagnosed to have IU. The tuberculin test was negative in both. Blood counts, erythrocyte sedimentation rate, and serum angiotensin convertase enzyme levels were normal. In both cases, the vitreous fluid tested positive for the T. gondii DNA sequence by using a uveitis DNA chip (XCyton Pvt. Ltd., Bangalore, India). It contained complimentary sequences to “signature genes” of T. gondii, Mycobacterium tuberculosis, M. chelonae, and M. fortuitum. The enzyme-linked immunosorbent assay (ELISA) detected elevated serum antitoxoplasma IgG levels in both. They responded to the antitoxoplasma therapy with oral co-trimoxazole (and additional intravitreal clindamycin in patient 1), with no recurrence during follow-ups of 6 and 8 months, respectively.

Changing Profile Of Organisms Causing Scleral Buckle Infections: A Clinico-microbiological Case Series

Purpose: To study the microbiological spectrum and in vitro susceptibility of bacterial isolates from explanted scleral buckles and to correlate clinical presentation to the causative agent. Method: Medical records of patients who underwent buckle explantation from July 2007 to May 2012 were reviewed retrospectively. Clinical features and microbiological profile were noted and correlated. Results: Twenty of 24 buckles (83.33%) from 24 patients grew 21 isolates. Isolates included 6 acid-fast bacilli (28.57%; atypical mycobacteria = 5, Nocardia asteroides = 1), 5 gram-positive bacilli (23.8%; Corynebacterium spp. = 4, Bacillus sp. = 1), 4 gram-positive cocci (19.0%; Staphylococcus spp. = 4), 2 gram-negative bacilli (9.5%; Pseudomonas aeruginosa = 2), and 4 fungi (19.0%; Aspergillus spp. = 3, Paecilomyces sp. = 1). Acid-fast bacilli and gram-negative bacilli were sensitive to amikacin and gram-positive bacilli and gram-positive cocci to vancomycin. Buckle exposure within 2 years of primary surgery tended to be noninfective (P = 0.06). Fungal or mycobacterial infections were more symptomatic than those with Corynebacterium species. Results of microscopic examination of conjunctival swab in 5 of 7 eyes (71.4%) were consistent with culture of conjunctival swab and explanted buckles. Conclusion: Clinical features and microscopic examination of conjunctival swab may give a lead toward the causative organism in suspected buckle infections. Based on these leads, vancomycin and amikacin may be used as the initial empirical therapy.

Investigating a viral aetiology for keratoconjunctivitis among patients with corneal scrapings positive for microsporidia.

Epidemic keratoconjunctivitis (EKC) occurs worldwide, affects a large number of individuals, is infectious, often seasonal and is usually known to be caused by human adenoviruses (HAdV serotype 4, 8, 19 and 37).1 Regular occurrence of EKC during the rainy seasons in Orissa, a state in eastern India, has been commonly observed by ophthalmologists in the area. However, the outbreaks have never been systematically investigated and the involvement of adenovirus has been taken for granted (personal communication, newspaper reports). In an earlier study, we reported the presence of microsporidial spores in the corneal scrapings of all such patients and for the first time we showed the association of microsporidia with a condition …

A 3½-Year Study of Bacterial Keratitis From Odisha, India.

PurposeTo report the clinical and microbiological characteristics and treatment outcome of bacterial keratitis at a tertiary eye care center in eastern India. DesignRetrospective analysis of medical and microbiology records. MethodsAll patients had undergone complete clinical and microbiological evaluation for microbial keratitis. Patients with laboratory-proven bacterial keratitis were included in the study. ResultsBetween July 2006 and December 2010, 1417 microbial keratitis was clinically diagnosed in the patients. Whereas no organisms were found in 27.8% (394/1417) of cases, 21.4% (303/1417) were bacterial. From 303 patients, 347 bacterial isolates were cultured, 260 (74.9%) of which were gram-positive, 67 were gram-negative, and 20 were acid-fast. Streptococcus pneumoniae was the predominant isolate (86/347 [24.7%]), followed by Staphylococcus species [64/347 (18.4%)]. Pseudomonas aeruginosa (29/347 [8.3%]) was the most common gram-negative bacterial isolate. High level of susceptibility to cefazolin (96.2%) and vancomycin (96.5%) was found in gram-positive cocci, whereas susceptibility of Pseudomonas species to gatifloxacin was 95.1%. Fifty-three patients (17.5%) required tissue adhesive, and 47 (15.5%) needed penetrating keratoplasty. Healed corneal scar was achieved in 188 patients (62%), whereas 34 (11.2%) were lost to follow-up. Large stromal infiltrate size, older age group, and poor presenting visual acuity were significant factors that adversely affected final outcome (P < 0.05). ConclusionsProportion of bacterial keratitis was low compared with other studies from India. Gram-positive bacteria were a common cause of bacterial keratitis with high susceptibility to cefazolin and vancomycin. Gram-negative bacteria were sensitive to gatifloxacin with overall good treatment outcome.