15년간 그람음성세균각막염의 임상적 고찰

Gram-Negative Bacterial Keratitis: A 15-Year Review of Clinical Aspects

목적: 그람음성균각막염에서 원인균, 항생제감수성, 임상양상 및 시력호전불량의 위험인자를 알아보고자 하였다. 대상과 방법: 1998년부터 15년 동안 그람음성균이 동정된 감염각막염 161안 169균주를 대상으로 후향적으로 조사하였다. 3년 간격, 5개의 기간으로 나누어 원인균주와 항생제감수성의 변화추이를 분석하였으며, 환자 역학과 임상적 특성을 대표 균주별로 비교하고 위험인자를 확인하였다. 결과: 그람음성균의 동정 비율은 1기(34.7%)에 비해 5기(73.2%)에서 유의하게 증가하였으며(p＜0.001), 흔한 균주는 Pseudomonas spp. (55예, 32.5%), Enterobacter spp. (41예, 24.3%), S. marcescens (33예, 19.5%) 순이었다. 항생제감수성은 cefepime (94.5%), levofloxacin (93.4%), ciprofloxacin (93.0%) 및 amikacin (92.3%) 등이 높았다. 노년기와 청장년기에서 발생이 많았으며, 선행요인으로 콘택트렌즈 착용과 외상이 많았다. 다른 균주들에 비해 S. marcescens는 상피재생이 짧았고(p=0.012) 치료 후 최대교정시력이 양호하였다(p=0.004). 시력호전불량의 위험인자는 초진 시 교정시력 0.1 미만(p＜0.001)과 중심부 각막병변(p=0.027)이었다. 결론: 세균각막염에서 그람음성균 동정 비율은 최근 증가하는 추세이며, Pseudomonas spp.가 가장 흔한 동정균이었고 시력예후는 S. marcescens가 가장 양호하였다. 그람음성세균각막염의 조기진단과 cefepime, quinolone, amikacin의 적절한 항생제 선택이 필요하다.

Purpose: In this study we investigated pathogenic organisms, antibiotic susceptibility, and clinical characteristics of patients with Gram-negative bacterial keratitis and elucidated risk factors for poor visual outcomes. Methods: The authors performed a retrospective chart review of 161 eyes (169 isolates) with Gram-negative bacterial keratitis between January 1998 and December 2012 at Yeungnam University Hospital. The study was divided into 5 periods for analysis of the bacteriological profiles and in vitro antibiotic sensitivity. The epidemiological and clinical characteristics were compared according to 3 groups (Pseudomonas species, Enterobacter species, and Serratia marcescens). Additionally, logistic regression analysis was performed to determine the risk factors. Results: The prevalence of Gram-negative organisms increased from 34.7 to 73.2% between the 1st and 5th periods (p < 0.001). Pseudomonas spp. was the most commonly isolated organism (55 eyes, 32.5%) over the total period, followed by Enterobacter spp. (41 eyes, 24.3%) and Serratia marcescens (33 eyes, 19.5%). The effective antibiotics against Gram-negative bacterial pathogens isolated from culture were cefepime (94.5%), levofloxacin (93.4%), ciprofloxacin (93.0%), and amikacin (92.3%). The incidence was higher in the elderly over 60 years of age and in early adulthood patients in their 20s and 30s. The frequent predisposing factors were contact lens wearing and corneal trauma. S. marcescens had the shortest corneal epithelium healing time (p = 0.012) and the most favorable visual outcome after treatment (p = 0.004) compared with the other species. Risk factors for poor visual outcomes included a best corrected visual acuity less than 0.1 at initial evaluation (p < 0.001) and central corneal lesion (p = 0.027). Conclusions: Gram-negative bacterial keratitis tended to increase and Pseudomonas spp. was the most common isolate. The clinical prognosis was most favorable in S. marcescens. Early diagnosis of Gram-negative bacterial keratitis and appropriate antibiotic selection including cefepime, quinolone, or amikacin are recommended.