Healthcare-Associated Infection Surveillance in Small and Medium Sized Hospitals / 병원감염관리

BACKGROUND: The purpose of this study is to know the healthcare-associated infection (HAI)s in small and medium sized hospitals, less than 400 beds. METHODS: We had web based surveillance for HAIs in 27 hospitals from August to October 2010. The surveillance performed in 1-2 ICUs and 1 general ward in each hospitals by CDC definition. And for the multi-drug resistant organisms (MDROs), we reviewed all of blood culture results. RESULTS: We identified 319 HAIs among 269,436 patients days. The HAIs rate was 1.18 (CI 1.05-1.32)/1,000 patient-days. Urinary tract infection was the most common HAI (52.4%) in this study followed by pneumonia (18.9%), blood-stream infections (14.2%), surgical site infection (7.9%), and others (6.6%). There were 76.5% of device associated infections in UTI, 46.7% in BSI, and 18.3% in pneumonia. The rate of HAIs in ICU was higher than that of in general ward (4.6 vs 0.9/1,000 patient-days). However, the indwelling catheter associated urinary tract infection rate was lower in ICU (2.6 vs 4.4/1,000 device days). There were no significant differences in central line-associated blood stream infection rate (1.5 vs 1.8) and ventilator-associated pneumonia rate (3.0 vs 0.0). The common microorganisms found in HAIs were Escherichia coli (19.8%), Staphylococcus aureus (13.1%), and Pseudomonas aeruginosa (12.7%). Moreover, 90.9% of S. aureus were resistant to methicillin, and 38.2% of P. aeruginosa and 44.4% of Acinetobacter baumannii were resistant to imipenem. Total of 66 MDROs were isolated from blood culture and the result shows that the MRSA was 84.6% (56 case), carbapenmen-resistant Acinetobacter spp. was 10.6% (7 case), and vancomycin-resistant enterococci was 4.6% (3 case). CONCLUSION: The characteristics of HAIs in small and medium sized hospitals will be contributed to the decision making of governance policy for infection control and to provide comparable data for these hospitals.

Prevention of Methicillin-Resistant Staphylococcus aureus Nasal carriage and Infection by Conventional Method and Intranasal Fusidic Acid / 병원감염관리

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major pathogens of nosocomial infections. Especially in intensive care units (ICUs) and nasal carriage of Staphylococcus aureus has been known as a major risk factor of staphylococcal infections. In Korea, MRSA is the most common pathogen of nosocomial infections in ICUs. We performed this study to investigate the effects of conventional control measures and the additional effect of intranasal fusidic acid in prevention of MRSA nasal carriage and infection in ICUs of one educational hospital in Korea. METHOD: All patients admitted to medical ICU and surgical ICU in Samsung medical center from April to September 1999 were studied prospectively. Surveillance culture was done in all patients and health care workers by nasal swab culture. We tried to control MRSA infection by conventional methods in the first period April-June 1999) and by additional intranasal fusidic acid application in the second period (July-September 1999) RESULTS: Comparing the first with second periods, new nasal MRSA colonization rate among patients was significantly decreased from 14.8% to 1.8% in surgical ICU (P=0.016). Although there was no statistical difference between the first and second periods in medical ICU (14.6% vs 5.9%, P=0.192), the new nasal colonization of the first period was significantly decreased than that of the previous study which was performed in 1996 (14.6% vs 36.2%, P=0.015). And new MRSA infection rate was much more decreased than the previous study, but there was no statistical significance (11.7% vs 2.0%, P=0.066). CONCLUSION: Conventional methods for MRSA control decreased new MRSA nasal colonization of patients in ICUs. Application of intranasal fusidic acid was considered as an additional control measure for reducing MRSA nasal colonization. For evaluating effect of intranasal fusidic acid for preventing of MRSA infection in ICUs, further study with larger scale of study population is warranted.

A Study on Modes of Transmission and Role of Nasal Carriage to Subsequent Infection with Methicillin-Resistant Staphylococcus aureus in Medical ICU Using PFGE / 병원감염관리

BACKGROUND: In Korea, methicillin-resistant Staphylococcus aureus (MRSA) is the most common nosocomial pathogen, which is particularly prevalent in ICU. We performed this study to investigate the modes of transmission of MRSA and the role of nasal carriage of11RSA to subsequent MRSA infections in medical ICU. METHODS: All patients admitted to the medical lCU during 10 months were studied prospectively. Nasal swabs were done in all patients within 24 hours of admission and weekly thereafter. For patients who developed MRSA infections, additional cultures were done before start of antibiotics. Surveillance cultures of nostril, hands of health care workers and environment were done once at the end of the study. Bacterial typing was performed with pulsed-field gel electrophoresis (PFGE) using Smal. RESULTS: Among 138 patients enrolled, 24 patients (17.4 %) were nasal colonizers, and 9 patients (6.5%) were already infected with MRSA prior to admission. New nasal colonization among patients, in whom follow up nasal cultures were done at the interval of 3 days or more, developed at 36.2 % (21/58 patients). New infections of MRSA in patients who were admitted for more than 3 days, developed at 11.7 % (13/111 patients). Patients in isolation room were infected with MRSA less frequently (P <0.05). No other risk factors for nasal colonization of MRSA or MRSA infections were found. There were no significant differences between nasal colonizers and non-colonizers in the incidence of MRSA infections. PFGE analysis of MRSA isolates from patients showed several major patterns, which were similar in both MRSA isolates obtained prior to admission and those acquired after admission. PFGE patterns of MRSA isolates from health care workers and environment were different from those of patients. CONCLUSION: Patients who were infected or colonized with MRSA seemed to be a major source for transmission of MRSA in medical ICU. In medical lCU, where MRSA were prevalent, nasal colonization was not related to the increased incidence of MRSA infections.