Microbial investigations in keratitis at the Sydney Eye Hospital

Abstract
We investigated 107 cases of presumed microbial keratitis amongst patients presenting to the Sydney Eye Hospital between October 1986 and August 1988 to determine the frequency of infection, the common causative organisms and those factors that predispose to corneal infection.
We found that 95% of culture-proven cases were caused by bacteria and that Staphylococcus epidermidis and Corynebacterium sp, accounted for 42.5% of these cases. All bacteria (except Staphylococcus epidermidis and Mycobacrerium chelonae ) were sensitive to gentamicin.
In 62.6% of cases, cultures for bacteria and fungi were negative. Retrospective review of the clinical records of these patients showed that herpes simplex virus, contact lens wear, staphylococcal marginal keratitis and recurrent erosion were important causes of keratitis in this group.     

Microbial investigations in keratitis at the Sydney Eye Hospital

We investigated 107 cases of presumed microbial keratitis amongst patients presenting to the Sydney Eye Hospital between October 1986 and August 1988 to determine the frequency of infection, the common causative organisms and those factors that predispose to corneal infection. We found that 95% of culture-proven cases were caused by bacteria and that Staphylococcus epidermidis and Corynebacterium sp. accounted for 42.5% of these cases. All bacteria (except Staphylococcus epidermidis and Mycobacterium chelonae) were sensitive to gentamicin. In 62.6% of cases, cultures for bacteria and fungi were negative. Retrospective review of the clinical records of these patients showed that herpes simplex virus, contact lens wear, staphylococcal marginal keratitis and recurrent erosion were important causes of keratitis in this group.     

The prevalence of adenoviral conjunctivitis at the Wills Eye Hospital Emergency Room.

OBJECTIVE: The aim of this study was to evaluate the prevalence of adenoviral conjunctivitis by analyzing data from a prospective clinical study of 50 consecutive patients presenting to the Wills Eye Hospital Emergency Room (WEH ER) with a clinical diagnosis of infectious conjunctivitis from July 2003 to October 2003. METHODS: The polymerase chain reaction (PCR) was used to evaluate all cases of clinically diagnosed infectious conjunctivitis. Based on the laboratory findings, the prevalence of adenovirus was determined. RESULTS: Of the 50 consecutive patients with acute infectious conjunctivitis, 31 patients were PCR positive for adenovirus. CONCLUSIONS: The prevalence of adenoviral conjunctivitis was found by PCR to represent 62% of all patients presenting with a clinical diagnosis of infectious conjunctivitis from July 2003 to October 2003.     

Spectrum of fungal keratitis in North India

PURPOSE: To report the epidemiologic features and laboratory results of 191 consecutive cases of fungal keratitis presenting to a tertiary level superspecialty teaching hospital of North India. METHODS: A prospective hospital-based study was carried out on 485 consecutive patients presenting with corneal ulcers to the outpatient department of Guru Nanak Eye Center, Maulana Azad Medical College, New Delhi, from January 1999 to June 2001. The sociodemographic data, predisposing risk factors, clinical details, prior treatment modalities, laboratory results, and visual outcomes were analyzed. RESULTS: Diagnosis of mycotic keratitis was established in 191 (39%) out of the total study group of 485 cases. Direct microscopic examination of KOH mounts and Gram-stained smears revealed presence of fungal elements in the corneal scrapings in 119 (62.3%) and 114 (60%) of the subsequently fungal culture-positive cases, respectively. Men (68%) were more commonly affected by fungal keratitis than women (32%). Young adults 31-40 years of age were the most common age group to be involved (36%). Predisposing risk factors were noted in 79%, with corneal trauma 42%, contact lens wear 25%, and topical corticosteroids in 21% patients. The spectrum of fungi isolated were Aspergillus species in 78 (41%) followed by Curvularia species in 55 (29%). CONCLUSIONS: In contrast to other studies from our subcontinent, we found Aspergillus niger to be the most common fungal isolate, followed by Curvularia species in culture-proven cases of fungal keratitis. Direct microscopic examination of KOH mounts emerged as a rapid, reliable, and inexpensive diagnostic modality, with a sensitivity of 62%, which would facilitate the institution of early antifungal therapy before the culture results became available, thus proving to be sight saving.     

Spectrum of fungal keratitis in central China

Purpose:  To investigate the epidemiology, risk factors, fungal spectrum and to test antifungal drug susceptibility of these isolates at a tertiary eye care referral centre in central China.
Methods:  The medical and microbiology records of 2064 culture-proven cases (2064 eyes) of fungal keratitis diagnosed at Henan Eye Institute between January 2000 to March 2009 was retrospectively reviewed. The fungal isolates were identified and a subgroup of 103 isolates were subjected to drug susceptibility tests for amphotericin B, fluconazole and ketoconazole by broth microdilution method.
Results:  A total of 2064 cases of confirmed fungal keratitis were identified. The predominant fungal species isolated was Fusarium spp. followed by Aspergillus spp. Alternaria spp. were another most common fungi in central China. Fungal keratitis was more common among men. A large proportion of the patients were middle-aged adults, and most were farmers. Ocular trauma was a highly significant risk factor and vegetative injuries were identified as a significant cause for fungal keratitis. Greatest number of cases of fungal keratitis was higher between September and December. Fusarium was mostly sensitive to amphotericin B, next to ketoconazole. Aspergillus was sensitive to amphotericin B and ketoconazole. Relatively, both Fusarium and Aspergillus were insensitive to fluconazole.
Conclusion:  Fusarium and Aspergillus are always the most isolated pathogens of fungal keratitis in central China, followed by Alternaria . Document available on the epidemiological features of a large series would greatly help ophthalmologists at primary and second health care centres in the management of this disease.     

中国华南地区真菌性角膜炎致病菌谱变化

背景 真菌性角膜炎发病率高,临床治疗比较困难,其病原学诊断和鉴定是改善疾病预后的前提.近年来随着地区环境和气候的不断变化,真菌性致病菌的菌属分布是否发生改变值得关注. 目的 分析近年来华南地区真菌性角膜炎致病菌的分布状况. 方法 对2009年1月至2014年12月在中山大学中山眼科中心收集和培养的化脓性角膜溃疡刮取标本3 350份进行回顾性分析,对真菌培养阳性率及致病真菌株的种属分布进行鉴定,并评估不同年段和不同季节的变化.结果 培养的3 350份标本中真菌培养阳性者1 050株(1 050例),每年平均175株,阳性率为31.34％,其中镰刀菌属337株,占32.10％;曲霉菌属270株,占25.71％;禾草蠕孢霉菌属150株,占14.29％;毛霉菌属96株,占9.14％;弯孢霉属与青霉菌属各65株,各占6.19％.2009-2010年培养的阳性菌株367株,占36.05％;2011-2012年阳性菌株329株,占32.45％;2013-2014年阳性菌株354株,占26.86％.各年段真菌检出阳性率的差异有统计学意义(x2=22.37,P＜0.01).1～3月培养的阳性菌株261株,占31.15％;4～6月阳性菌株182株,占25.53％;7～9月阳性菌株237株,占30.00％;10 ～ 12月阳性菌株370株,占36.67％;各季度间阳性菌株检出率的差异有统计学意义(x2=25.19,P＜0.01),各种致病真菌的检出率以10～ 12月最高,4～6月最低.结论 中国华南地区真菌性角膜溃疡的致病菌以镰刀菌属居首位,其次依次为曲霉菌属、禾草蠕孢霉菌属、毛霉菌属、膝曲弯孢霉菌属和青霉菌属.真菌感染率最高的季节是10 ～12月.2009-2014年真菌性角膜溃疡仍处于高发期,但在华南地区发病率呈下降趋势.     

Infectious keratitis in Vietnam: etiology, organisms, and management at Vietnam National Eye Hospital

AIM:To report the etiologies,risk factors,treatments,and outcomes of infectious keratitis(IK)at a major Vietnamese eye hospital.METHODS:This is a retrospective review of all cases of IK at Vietnam National Eye Hospital(VNEH)in Hanoi,Vietnam.Medical histories,demographics,clinical features,microbiological results,and treatment outcomes were reviewed.RESULTS:IK was diagnosed in 1974 eyes of 1952 patients,with ocular trauma being the greatest risk factor for IK(34.2%),frequently resulting from an agriculturerelated injur y(53.3%).The mean duration between symptom onset and presentation to VNEH was 19.3±14.4 d,and 98.7%of patients had been treated with topical antibiotic and/or antifungal agents prior to evaluation at VNEH.Based on smear results of 1706 samples,the most common organisms identified were bacteria(n=1107,64.9%)and fungi(n=1092,64.0%),with identification of both bacteria and fungi in 614(36.0%)eyes.Fifty-five of 374 bacterial cultures(14.7%)and 426 of 838 fungal cultures(50.8%)were positive,with the most commonly cultured pathogens being Pseudomonas aeruginosa,Streptococcus pneumonia,Fusarium spp.,and Aspergillus spp.Corneal perforation and descemetocele developed in 391(19.8%)and 93(4.7%)eyes,respectively.Medical treatment was successful in resolving IK in 50.4%eyes,while 337(17.1%)eyes underwent penetrating or anterior lamellar keratoplasty.Evisceration was performed in 7.1%of eyes,most commonly in the setting of fungal keratitis.CONCLUSION:Ocular trauma is a major risk factor for IK in Vietnam,which is diagnosed in almost 400 patients each year at VNEH.Given this,and as approximately one quarter of the eyes that develop IK require corneal transplantation or evisceration,greater emphasis should be placed on the development of prevention and treatment programs for IK in Vietnam.     

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.     

Changing trends in the clinical course and outcome of bacterial keratitis at King Khaled Eye Specialist Hospital

Objective To evaluate changes in the predisposing factors and causative organisms, clinical course, and outcome of bacterial keratitis at King Khaled Eye Specialist Hospital (KKESH) between 1995 and 2005. Methods Retrospective review of 78 and 103 cases of culture-positive bacterial keratitis admitted to KKESH in 1995 and 2005. Main outcome measures Microbiological cure, visual outcome. Results There was little change in the predisposing factors for bacterial keratitis, initial clinical severity, or the microbiological profile between 1995 and 2005. While similar topical fortified antibiotic therapy regimens were used in both 1995 and 2005, there was a significant increase in the use of topical corticosteroids in 2005 (P < 0.001), either alone or in combination with medroxyprogesterone 1% and doxycycline. There were significant improvements in the percentage of eyes achieving microbiological cure with medical therapy alone (76.0 vs. 92.2%, P = 0.002) or in combination with surgical intervention (92.4 vs. 100.0%; P = 0.005). The percentage of eyes requiring enucleation or evisceration due to treatment failure declined significantly from 7.6 to 0% (P = 0.006). There was a significant improvement in the percentage of eyes achieving a final visual acuity ≥20/40 (10.1 vs. 29.1%, P = 0.001). Conclusions Significantly better clinical outcomes were achieved in 2005 compared to 1995. Increased emphasis on management of inflammation in conjunction with the infectious process may have contributed to the improved outcomes.