Morlet N, Minassian D, Butcher J
Br J Ophthalmol. 1999 Sep;83(9):1027-31. doi: 10.1136/bjo.83.9.1027.
Primary treatment for suspected microbial keratitis is generally successful. Although risks such as contact lens use are well recognised as causative factors for microbial keratitis, little is known about the risk factors that influence treatment outcome. The present study evaluates the risk factors assessed at diagnosis as prognostic indicators of primary treatment failure.
Patients were prospectively enrolled in the ofloxacin treatment trial and data concerning symptoms, treatments, past and concurrent eye disease were collected along with the measurement of corneal ulcer size at the slit lamp. All patients were scraped for microbiological investigation, and treated with either ofloxacin (0. 3%) or standard therapy of fortified cefuroxime and gentamicin drops. Treatment success was complete healing of the ulcer with zero dimensions of the epithelial defect within 2 weeks of start of treatment. The important prognostic indicators were selected by comparison among those who failed treatment, had delayed healing, or were culture positive with other patients using univariate and stratified analysis. These were then used in a Poisson model for multiple regression analysis to estimate the relative risk of the main prognostic variables.
Of the 118 patients enrolled in the study, 14 were identified as primary treatment failures, 17 had slow healing, and 15 indolent ulcers. There were 49 culture positive patients. The multivariate analysis identified that large culture positive ulcers in patients 60 years or older had 5.5 times the risk of primary treatment failure (p<0.001). Significant predictors of slow healing were previous ocular disease and a positive culture; significant predictors of indolent ulceration were previous ocular disease and steroid use at diagnosis; the main predictor of a culture positive result was ulcer size.
Elderly patients with large ulcers were more likely to be culture positive, fail primary therapy, and require surgical intervention. A positive microbial culture provided prognostic information regardless of the organism isolated. However, this information was of less value for those with small ulcers and for younger patients.
疑似微生物性角膜炎的初始治疗通常是成功的。尽管诸如佩戴隐形眼镜等风险已被公认为微生物性角膜炎的致病因素，但对于影响治疗结果的危险因素却知之甚少。本研究评估了在诊断时评估的危险因素作为初始治疗失败的预后指标。
前瞻性纳入患者进行氧氟沙星治疗试验，收集有关症状、治疗、既往和并发眼病的数据，同时在裂隙灯下测量角膜溃疡大小。所有患者均进行刮片进行微生物学检查，并用氧氟沙星（0.3%）或强化头孢呋辛和庆大霉素滴眼液的标准疗法进行治疗。治疗成功定义为在开始治疗后2周内溃疡完全愈合且上皮缺损尺寸为零。通过对治疗失败、愈合延迟或培养阳性的患者与其他患者进行单因素和分层分析比较，选择重要的预后指标。然后将这些指标用于泊松模型进行多元回归分析，以估计主要预后变量的相对风险。
在纳入研究的118例患者中，14例被确定为初始治疗失败，17例愈合缓慢，15例为顽固性溃疡。有49例培养阳性患者。多因素分析确定，60岁及以上患者中培养阳性的大溃疡初始治疗失败风险是其5.5倍（p<0.001）。愈合缓慢的显著预测因素是既往眼部疾病和培养阳性；顽固性溃疡的显著预测因素是既往眼部疾病和诊断时使用类固醇；培养阳性结果的主要预测因素是溃疡大小。
患有大溃疡的老年患者更可能培养阳性、初始治疗失败并需要手术干预。微生物培养阳性提供了预后信息，无论分离出何种微生物。然而，对于小溃疡患者和年轻患者，此信息的价值较小。
