Predisposing factors and etiologic diagnosis of ulcerative keratitis

PURPOSE: To determine the predisposing factors, demographic characteristics, and etiology of ulcerative keratitis in a referral center in Bangkok, Thailand. METHODS: The medical records of admitted patients with positive-culture ulcerative keratitis were retrospectively reviewed for demographic data, predisposing factors, and microbial culture results. Predisposing factors were compared between bacterial and fungal keratitis. RESULTS: From January 2001 to December 2004, there were 127 positive-culture ulcerative keratitis cases. The most frequent microbiological diagnosis was bacterial keratitis (76 eyes, 60%), followed by fungal (48 eyes, 38%) and Acanthamoeba keratitis (3 eyes, 2%). The most common organisms isolated were Pseudomonas spp. for bacteria and Fusarium spp. for fungus. Compared with bacterial keratitis, fungal keratitis was more likely to be associated with ocular trauma (odds ratio = 11.20; 95% confidence interval, 3.62-34.66) but less likely to be associated with contact lens wear (odds ratio = 0.02; 95% confidence interval, 0.01-0.08). CONCLUSIONS: In our study, Pseudomonas and Fusarium species are the most common causes of bacterial and fungal keratitis, respectively. Fungal keratitis was more likely than bacterial keratitis to be associated with ocular trauma, whereas fungal keratitis was less likely to be associated with contact lens wear.     

Evaluation of corneal scraping smear examination methods in the diagnosis of bacterial and fungal keratitis: a survey of eight years of laboratory experience

PURPOSE: To determine the sensitivity, specificity, and predictive values of Gram and potassium hydroxide with calcofluor white (KOH+CFW) stains in the diagnosis of early and advanced microbial keratitis, a retrospective analysis of comparative data from a prospectively collected database was done. METHODS: Patients with nonviral microbial keratitis seen at L.V. Prasad Eye Institute between February 1991 and December 1998 were included in the study. The type of bacteria seen on Gram stain was determined from 251 corneal scrapings from patients with early keratitis and 841 corneal scrapings from patients with advanced keratitis. The presence of fungi in corneal scrapings was determined by KOH+CFW stain of 114 and 363 scrapings from patients with early and advanced keratitis, respectively. The smear findings were compared with culture results to analyze specificity, sensitivity, and predictive values of the staining techniques. RESULTS: The sensitivity of Gram stain in the detection of bacteria was 36.0% in early and 40.9% in advanced keratitis cases; however, the specificity was higher in both groups (84.9% and 87.1%, respectively). Comparatively, the sensitivity and specificity of fungal detection were higher using KOH+CFW in early (61.1% and 99.0%, respectively) as well as advanced keratitis (87.7% and 83.7%, respectively). Predictive values were high for KOH+CFW in fungus detection, while they were poor for Gram stain in bacteria detection. In advanced keratitis cases, the false positives were higher in fungal detection (16.3%) than in bacterial detection (10.3%), while the false negatives were significantly higher in bacterial detection compared with fungal detection (59.1% versus 12.3%, p< 0.0001). In early keratitis, on the other hand, both false positives and false negatives for bacterial detection were significantly higher than fungal detection. CONCLUSIONS: Decisions can reliably be based on KOH+CFW stain of corneal scrapings for initiation of antifungal therapy in mycotic keratitis. The results of Gram stain, on the other hand, have limited value in therapeutic decisions for bacterial keratitis. Therefore, the search for a better modality for early and efficient diagnosis of bacterial keratitis needs to continue.     

1054例化脓性角膜炎的回顾性分析

目的探讨化脓性角膜炎的病原学和临床特征。方法对1999年1月至2004年12月间于山东省眼科研究所、青岛眼科医院诊治的1054例化脓性角膜炎住院患者的人口学特征、症状持续时间、疾病危险因素、就诊前接受的治疗及实验室检查结果等资料进行回顾性分析。结果化脓性角膜炎中真菌性角膜炎所占比例最高（61．9％）,41～50岁的中年患者（27．3％）和农民（82．9％）最多见。角膜损伤是最常见的发病危险因素。氢氧化钾湿片直接镜检法诊断真菌性角膜炎的阳性率为88．7％,而革兰染色镜检法检查细菌性角膜炎的阳性率仅为43．4％。分离到的真菌中镰刀菌属占73．3％,其次为曲霉菌属（12．1％）。分离到的细菌病原谱中,以铜绿假单胞菌居多（35．7％）,其次为表皮葡萄球菌（22．5％）。结论真菌性角膜炎在严重的化脓性角膜炎中最常见且呈现逐年递增的趋势。氢氧化钾湿片直接镜检法是一种快速、简便及有效的真菌性角膜炎诊断工具。     

Suppurative keratitis in rural Bangladesh: the value of Gram stain in planning management

External eye diseases which result in corneal scarring are an important cause of blindness in Bangladesh and at the Chittagong Eye Infirmary and Training Complex (EITC) over 200 cases of suppurative keratitis are managed each year. We reviewed the records of 127 cases of microbial keratitis to determine the relative contributions of Gram stain and culture to diagnosis of the causative organism. There were 107 culture-proven cases of microbial keratitis amongst the 127 patients in this study. Gram stain was positive in 89 cases which represents 70% of the total and 83% of all culture-proven cases. Streptococcus pneumoniae and Pseudomonas sp were the commonest bacteria isolated and Aspergillus sp and Fusarium sp the commonest fungi. In 20 cases (16%) no organism was isolated on Gram stain or culture. Our results support the use of both Gram stain and culture in isolation of the causative organism in cases of suppurative keratitis in Bangladesh. However the low cost of Gram stain and its useful recovery rates for both bacteria and fungi support its use as an initial investigation for microbial keratitis at the secondary level of eye care in rural Bangladesh.     

Fungal keratitis in a daily disposable soft contact lens wearer.

PURPOSE: To report the first case of fungal keratitis in a patient wearing daily disposable soft contact lenses. METHODS: Case Report. A 20-year-old white female in good health developed a corneal ulcer in her lefteye associated with daily disposable soft contact lens wear. There was no history of trauma to the left eye, and she denied overnight wear. Corneal scrapings were taken, and the patient was started on intensive tobramycin 14 mg/mL and cefazolin 50 mg/mL topical therapy for suspected bacterial keratitis. After 3 days of antibacterial therapy, the ulcer worsened. The cultures were negative as were the Gram stain and Gomori's methenamine silver stain. Initial cultures and stains were then repeated with the addition of a culture for herpes simplex virus. The developing clinical picture was suspicious for fungal keratitis. The patient was then started on intensive vancomycin 2%, natamycin 5%, and continued on fortified tobramycin. Three days after the second corneal scrapings were performed, a positive fungal culture was obtained for Fusarium sp. Vancomycin and tobramycin were then discontinued and amphotericin B 0.15% was added to natamycin 5% with the continuation of intensive topical therapy. RESULTS: The patient's keratitis was successfully treated with intensive double antifungal therapy. CONCLUSIONS: Infectious keratitis in daily disposable soft contact lens wear is an unusual occurrence. To our knowledge, there is no previous case of fungal keratitis occurring in patients wearing daily disposable lenses. This case emphasizes the importance of considering fungus in the differential diagnosis for keratitis even in daily disposable contact lens wearers.     

Epidemiological and microbiological diagnosis of suppurative keratitis in Gangetic West Bengal, eastern India

PURPOSE: To determine the epidemiological pattern and risk factors involved in suppurative corneal ulceration in Gangetic West Bengal, eastern India, and to identify the specific microbial agents responsible for corneal infections. METHODS: All patients with suspected microbial keratitis presenting to the corneal clinic at Disha Eye Hospital, Barrackpore, West Bengal, India, from January 2001 to December 2003 were evaluated. Sociodemographic data and information pertaining to the risk factors were recorded. After diagnosing infective corneal ulcer clinically, corneal scraping and cultures were performed. RESULTS: Over a three-year period, 1198 patients with suppurative keratitis were evaluated. Ocular trauma was the most common predisposing factor in 994 (82.9%) patients (P< 0.0001), followed by use of topical corticosteroids in 231 (19.28%) patients. Cultures were positive in 811 (67.7%) patients. Among these culture positive cases, 509 (62.7%) patients had pure fungal infections (P< 0.001), 184 (22.7%) patients had pure bacterial infections and 114 (14.1%) had mixed fungal with bacterial infections. Acanthamoeba was detected in 4 (0.49%) patients. The most common fungal pathogen was Aspergillus spp representing 373 (59.8%) of all positive fungal cultures (P< 0.0001), followed by Fusarium spp in 132 (21.2%) instances. Most common bacterial isolate was Staphylococcus aureus, representing 127 (42.6%) of all the bacterial culture (P< 0.0001) followed by Pseudomonas spp 63 (21.1%). CONCLUSION: Suppurative keratitis in Gangetic West Bengal, most often occurs after a superficial corneal trauma with vegetative or organic materials. Fungal ulcers are more common than bacterial ulcers. Aspergillus spp and Staphylococcus aureus were the most common fungus and bacteria respectively. These "regional" findings have important public health implications for the treatment and prevention of suppurative corneal ulceration in this region of India.     

海南省81例真菌性角膜溃疡病原学分析

目的:探讨中国海南省真菌性角膜溃疡的病原学特点及流行病学特征.方法:收集2014-01/2016-12在中山大学中山眼科中心海南眼科医院住院治疗的真菌性角膜溃疡确诊病例81例81眼的基本资料.分析致病真菌种群分布特点、患者年龄分布特点、患病季节分布构成比以及疾病危险因素.回顾分析真菌性角膜溃疡治疗方式,计算角膜溃疡坏死组织的真菌培养及鉴定、真菌涂片结果阳性率,卡方检验比较两种实验室检查方法阳性检出率.结果:选取临床诊断真菌性角膜溃疡患者81例81眼,其中男54眼,女27眼,年龄中位数51岁.角膜外伤是最常见的危险因素.≥50岁患病人数45眼(55%),占比最大;其次为>30~<50岁年龄段人群组28眼(35%);≤30岁人群组8眼(10%),占比最小.第一季度是全年真菌性角膜溃疡的高发时段,患病人数占36%.81份真菌培养样本阳性例数71眼,阳性率88%.80份角膜坏死物涂片样本,阳性样本共41眼,阳性率51%.真菌涂片阳性检出率低于真菌培养,差异有统计学意义(x2=23.730, P<0.01).主要致病性真菌依次为镰刀菌属34眼(48%),不产孢子菌11眼(15%).治疗上均采用了多种抗真菌药物治疗,23眼(28%)联合角膜清创+结膜瓣遮盖术治疗;9眼(11%)联合角膜移植术;7眼(9%)联合眼内容物剜除术.结论:中国海南省本岛真菌性角膜溃疡的最主要致病菌是镰刀菌属、不产孢子菌,高发季节为1~3mo.患者多有角膜外伤史.抗真菌药物及手术治疗是目前真菌性角膜溃疡的主要治疗手段.与真菌涂片相比较,真菌培养具有更高的阳性检出率.     

Fungal keratitis in a soft contact lens wearer.

PURPOSE: To describe a case of fungal keratitis in a soft contact lens wearer. METHODS AND RESULTS: A 57 year old female, compliant, frequent replacement soft contact lens wearer, with a possible prior history of herpes simplex keratitis, presented with pain and injection of her left eye of four weeks duration. Gram stain of a corneal ulcer of the left eye revealed fungal organisms and cultures grew Fusarium solani. The infiltrate responded to topical and systemic antifungal agents, but a corneal perforation developed which required a therapeutic penetrating keratoplasty. CONCLUSIONS: Fungal infections are a cause of corneal ulcers in contact lens wearers. Despite the use of topical and systemic antifungal agents, fungal ulcers frequently require surgical intervention.     

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.     

长江中下游地区真菌性角膜炎发病特征及转归分析

目的:分析长江中下游地区真菌性角膜炎流行病学特征及治疗预后状况。方法:对2004-01/2009-12我院212例212眼确诊为真菌性角膜炎患者的完整资料进行回顾性分析,调查内容包括职业、发病时间、发病原因、就诊经过、治疗情况及转归等。结果:患者中男159例,女53例,平均年龄44.5岁。职业为农民者177例(83.5%)。98例(46.2%)患者有明确植物性外伤史或接触史。发病时间在10～12月份者136例(64.2%)。从发病到我院平均就诊时间为24.1d。就诊时视力<0.05者158眼(74.5%)。眼部标本真菌培养阳性者194例(91.5%),主要致病菌属为镰刀菌属144株(74.2%),其次为曲霉菌属16株(8.3%),暗色孢科真菌共32株(15.1%),念珠菌属2株(1.0%)。117例(55.2%)患者经药物治疗好转;59例(27.8%)患者行角膜移植术,植片透明率64.4%;20例(9.4%)行球结膜瓣遮盖术治愈。随访6～25mo,最终视力<0.05者63眼(29.7%);眼球保存率96.6%。结论:长江中下游地区真菌性角膜炎高发季节为10～12月份,高发人群为中青年农民,主要致病菌属为镰刀菌属,积极的药物和手术治疗是挽救眼球、保存视力的有效手段。     

恩施地区外伤性真菌性角膜炎回顾性分析

目的 了解恩施地区外伤性真菌性角膜炎临床流行病学特点.方法 回顾性分析2009年7月至2013年6月恩施州中心医院收治的外伤性真菌性角膜炎病例.记录患者人口学特征、病史、职业、致伤原因、病程、先前诊断用药情况,来院后裂隙灯检查、微生物学检查、治疗方法、转归及随访结果,对资料进行分析.结果 4年间,69例（69眼）根据患病诱因、微生物学检查结果诊断为外伤性真菌性角膜炎.随访时间1 ～14个月.男51例,女18例,年龄27 ～71岁.农民64例.主要诱因为植物外伤.外院曾经过微生物学检查诊断为真菌性角膜炎2例.来院后沙氏培养基培养阳性67例,其中镰刀菌属54例（80.6％）,曲霉菌属10例（14.9％）.59例用药物治愈,清创及板层切除术8例,穿透性角膜移植术1例,眼球摘除1例.结论 恩施地区外伤性真菌性角膜炎首位病原体是镰刀菌属,多见于青壮年男性农民,植物外伤是主要原因,可导致严重视力损害.     

Corneal infection in Shandong peninsula of China: a 10-year retrospective study on 578 cases

AIM: To determine the epidemiological characteristics, clinical signs, laboratory findings, and outcomes in patients with corneal infection in Shandong peninsula of China. METHODS: The medical records of 578 inpatients (578 eyes) with corneal infection were reviewed retrospectively for demographic characteristics, risk factors, seasonal variation, clinical signs, laboratory findings, and treatment strategy. Patient history, ocular examination findings using slit-lamp biomicroscopy, laboratory findings resulted from microbiological cultures, and treatment. RESULTS: Fungal keratitis constituted 58.48% of cases of infectious keratitis among the inpatients, followed by herpes simplex keratitis (20.76%), bacterial keratitis (19.03%) and acanthamoeba keratitis (1.73%). The most common risk factor was corneal trauma (71.80%). The direct microscopic examination (338 cases) using potassium hydroxide (KOH) wet mounts was positive in 296 cases (87.57%). Among the 298 fungal culture-positive cases, Fusarium species were the most common isolates (70.47%). A total of 517 cases (89.45%) received surgical intervention, including 255 (44.12%) cases of penetrating keratoplasty, 74 (12.80%) cases of lamellar keratoplasty which has become increasingly popular, and 77 cases (13.32%) of evisceration or enucleation. CONCLUSION: At present, infectious keratitis is a primary corneal disease causing blindness in China. With Fusarium species being the most commonly identified pathogens, fungal keratitis is the leading cause of severe infectious corneal ulcers in Shandong peninsula of China.     

Epidemiological and microbiological profile of infective keratitis in Ahmedabad

Context:

Study of patients attending tertiary care ophthalmology institute at Ahmedabad.

Aims:

To study the microbiological etiology and epidemiological factors associated with suppurative keratitis.

Settings and Design:

A total of 150 corneal scrapings were evaluated from patients presenting with corneal ulcers at a tertiary ophthalmology center, Ahmedabad from July 2007 to June 2008.

Materials and Methods:

Scrapings were subjected to Gram stain, potassium hydroxide preparation and culture for bacterial and fungal pathogens. Socio-demographic data and risk factors were recorded.

Results:

Ninety percent (135/150) people with corneal ulcers had trauma as predisposing factor for keratitis. Trauma due to wooden objects was the leading cause (46/135) followed by vegetable matter and stone injury (23/135). Microbial etiology was established in 59.3% (89/150) of scrapings. Out of 89 positive isolates, 65.1% (58/89) were bacterial while 34.9% (31/89) were fungal. Among the bacterial isolates, 60.3% (35/58) were Gram-positive cocci while 39.7% (23/58) were Gram-negative bacilli. The most common bacterial isolate was Staphylococus aureus (32.7%, 19/58) followed by coagulase-negative Staphylococci (25.8%, 15/58) and Pseudomonas (18.9%, 11/58). Among the 31 fungal pathogens, Aspergillus species was the most common (35.4%11/31), followed by Fusarium species (22.5%, 7/31).

Conclusion:

Trauma with wooden material is the most common predisposing factor for suppurative keratitis. Males were more affected than females. Bacterial ulcers were more common than fungal in areas in and around Ahmedabad. Staphylococcus aureus and Aspergillus were the commonest bacterial and fungal isolates respectively. Geographical variation persists in microbial etiology of suppurative keratitis.     

Microbial keratitis in Waikato, New Zealand

Background: Bacterial keratitis is a potentially sight‐threatening condition. This study is performed to identify the common causative organisms for bacterial keratitis in Waikato region and the antibiotic sensitivities to these organisms. Design: Retrospective, observational, case series. Participants: The microbiology records of all patients with bacterial keratitis who presented to the Ophthalmology department, Waikato Hospital, New Zealand between January 2003 and December 2007. Methods: The corneal scrape results were reviewed. Antibiotic sensitivity for the organism was tested following National Committee for Clinical Laboratory Standards (NCCLS) method. Main Outcome Measures: In vitro laboratory susceptibility testing of ocular isolates to various antibiotics. Results: A total of 265 scrapes were performed. Gram stain was positive in 35 (13.2%) eyes. Positive culture was seen in 174 (65.6%) scrapes; 78.2% were Gram‐positive and 20.2% were Gram‐negative organisms. Most common Gram‐positive organisms were coagulase‐negative Staphylococci (40.8%) and Staphylococcus aureus (11.5%). Most common Gram‐negative organisms were Moraxalla species (8.0%) and Pseudomonas aeroginosa (3.4%). Of the bacterial organisms 99% were sensitive to ciprofloxacin. All Gram‐negative organisms and 95.5% Gram‐positive organisms were sensitive to tobramycin; 96.6% Gram‐positive organisms and 98.3% Gram‐negative organisms were sensitive to cefuroxime. Conclusions: Our results are comparable to other regions in New Zealand but the incidence of coagulase‐negative Staphylococcus is much higher in this region compared with other New Zealand studies. It seems appropriate to start patients with corneal ulcers initially on fluoroquinolone monotherapy while awaiting culture results.     

Efficacy of topical and systemic itraconazole as a broad-spectrum antifungal agent in mycotic corneal ulcer. A preliminary study

PURPOSE: To evaluate the efficacy of topical (1%) and systemic itraconazole against common fungi such as Aspergillus and other filamentous fungi that cause mycotic corneal ulcer. METHODS: A prospective randomised, controlled study was done in 54 clinically suspected cases of fungal keratitis of which 44 were culture proven. Half the cases (n=27) with superficial involvement were treated with only topical itraconazole (1%) and the other half were treated with both topical and systemic itraconazole. RESULTS: Aspergillus, Penicillium and Fusarium were the most common fungi isolated. The ulcer resolved in 42 eyes (77%) and 12 eyes (23%) did not respond well to treatment. Four of 12 non-responding eyes were caused by Fusarium species. CONCLUSION: Itraconazole, given either topically or systemically, is effective in treating mycotic corneal ulcers.     

Analysis of bacterial cultures in infectious keratitis, 1997 to 2004

PURPOSE: To review bacterial culture results in infectious keratitis at a tertiary referral center. DESIGN: Retrospective case series. METHODS: Analysis of Gram stain, bacterial culture, and targeted antibiotic sensitivities of all cases of presumed infectious keratitis at Duke University Eye Center from 1997 to 2004 (n = 453). RESULTS: Cultures were positive in 307 cases (68%); 21% demonstrated polymicrobial growth. Among 388 isolates, 81% were Gram-positive. Gram stain results were available in 334 cases, demonstrating 18% sensitivity and 94% specificity. Antibiotic sensitivities revealed 24% resistance of tested S. aureus isolates to cefazolin, and <5% resistance of tested gram-negative isolates to various antibiotics, with no statistically significant increase from 1997 to 2004. CONCLUSIONS: In this study, the microbial profile has remained stable from 1997 to 2004. Gram stain studies were of poor sensitivity, while culture yields were significantly higher and demonstrated a relatively high polymicrobial infection rate. Increasing antibiotic resistance was not clearly demonstrated.     

天津地区角膜外伤后真菌感染的病原学调查分析

目的调查分析天津地区角膜真菌感染的病原菌种类。方法自2006年1月至2009年6月间,在天津市眼科医院采集角膜外伤后疑似真菌性角膜炎病变角膜标本170份,分别进行真菌直接涂片镜检和接种于沙保罗培养基进行真菌培养,对培养阳性者进行菌种鉴定。结果在170份角膜病变标本中,直接涂片镜检阳性98份,阳性率为57．65％。真菌培养阳性123株,阳性率为72．35％;涂片镜检和真菌分离培养的一致性为84．75％。其中镰刀菌属占66．67％,镰刀菌属中茄病镰刀菌占30．89％,尖孢镰刀菌占15．45％,串珠镰刀菌占13．82％。曲霉菌属占23．58％,曲霉菌属中黄曲霉菌占13．01％,烟曲霉菌占8．14％。结论镰刀菌属和曲霉菌属是天津地区眼部真菌感染的主要致病真菌。     

Rapid streptococcal antigen detection in experimental keratitis

We assessed the role of commercially available immunodiagnostic procedures in comparison to Gram stain and culture in experimental bacterial keratitis. Rabbit corneas were inoculated with Streptococcus pneumoniae, S. pyogenes, S. faecalis, or Haemophilus influenzae. Corneal scrapings were processed before and during antibacterial therapy using a coagglutination assay to detect pneumococcal capsular antigen (Phadebact Pneumococcus test) and an enzyme immunoassay to detect group A streptococcal cell-wall antigen (TestPack Strep A test). In untreated infected eyes, both immunoassays were highly specific and as sensitive as Gram stain for detection of the respective microorganisms. For S. pneumoniae keratitis, the sensitivity of coagglutination was 82% and Gram stain, 73%. For S. pyogenes keratitis, the sensitivity of enzyme immunoassay was 100% and Gram stain, 62%. Immunoassays and Gram stain were less sensitive than culture during antibacterial therapy. Successful clinical application of the coagglutination assay in a patient with pneumococcal keratitis permitted early use of specific cephalosporin treatment.     

Bacterial keratitis: predisposing factors,clinical and microbiological review of 300 cases

AIM: To identify predisposing factors and to define clinical and microbiological characteristics of bacterial keratitis in current practice. METHODS: A retrospective analysis of the hospital records of patients presenting with bacterial keratitis and treated at the Quinze-Vingts National Center of Ophthalmology, Paris, France, was performed during a 20 month period. A bacterial keratitis was defined as a suppurative corneal infiltrate and overlying epithelial defect associated with presence of bacteria on corneal scraping and/or that was cured with antibiotic therapy. Risk factors, clinical and microbiological data were collected. RESULTS: 300 cases (291 patients) of presumed bacterial keratitis were included. Potential predisposing factors, usually multiple, were identified in 90.6% of cases. Contact lens wear was the main risk factor (50.3%). Trauma or a history of keratopathy was found in 15% and 21% of cases, respectively. An organism was identified in 201 eyes (68%). 83% of the infections involved Gram positive bacteria, 17% involved Gram negative bacteria, and 2% were polymicrobial. Gram negative bacteria were associated with severe anterior chamber inflammation (p=0.004), as well as greater surface of infiltrates (p=0.01). 99% of ulcers resolved with treatment, but only 60% of patients had visual acuity better than the level at admission, and 5% had very poor visual outcome. CONCLUSIONS: Contact lens wear is the most important risk factor. Most community acquired bacterial ulcers resolve with appropriate treatment.     

Spectrum of fungal keratitis:clinicopathologic study of 44 cases

AIM:To determine the causative agents of fungal keratitis and study the predisposing factors over a period of ten years in a single tertiary care hospital.METHODS:A retrospective analysis of fungal corneal ulcers was done from 2003-2012. Patients’ clinical data were noted from the file records. Correlation of histopathological diagnosis was done with the report on fungal culture.RESULTS: Mycotic keratitis was established in 44 cases by a positive fungal culture. Direct microscopic examination of potassium hydroxide (KOH) mounts revealed fungal elements in 39 cases while 40 cases showed fungus on Gram stained smears. Males (54.55%) were more commonly affected than the females (45.45%). The age ranged from 18 to 82 years. Most common age group to be involved was 41-60 years. Predisposing risk factors were seen in 34 (77.27%) cases. Most common findings on clinical examination were anterior chamber reaction and conjunctival injection seen in all the cases. Other common findings were stromal infiltration and hypopyon seen in 20 (45.45%) and 18 (40.91%) cases respectively. On histopathological examination the fungus was typed, as aspergillus in 34 cases while no definite typing was possible in 10 cases. The predominant isolate was aspergillus flavus (59.09%) followed by fusarium (15.91%). Mixed fungal and bacterial infection was seen in 3 (6.82%) cases.CONCLUSION:Although culture is the gold standard for definitive diagnosis of fungal keratitis, direct microscopic examination of corneal scrapings or histomorphological evaluation of biopsies allow a rapid preliminary diagnosis. Early administration of antifungal treatment helps in preventing dreadful complications.