The clinical and economic burden of community-onset complicated skin and skin structure infections in Korea

Background/Aims@#To investigate epidemiologic characteristics, clinical and economic burdens, and factors associated with mortality in complicated skin and skin structure infection (cSSSI) patients in Korea. @*Methods@#A retrospective, observational, nationwide study was conducted between April to July 2012 at 14 tertiary-hospitals in Korea. Eligible patients were hospitalized adults with community acquired cSSSI, who underwent surgical intervention and completed treatment between November 2009 and October 2011. Data on demography, clinical characteristics, outcomes and medical resource utilization were collected through medical record review. Direct medical costs were calculated by multiplying quantities of resources utilized by each unit price in Korea. @*Results@#Of 473 patients enrolled, 449 patients (except 24 patients with no record on surgical intervention) were eligible for analysis. Microbiological testing was performed on 66.1% of patients and 8.2% had multiple pathogens. Among culture confirmed pathogens (n = 297 patients, 340 episodes), 76.2% were gram-positive (Staphylococcus aureus; 41.2%) and 23.8% were gram-negative. The median duration of hospital stay was 16 days. Among treated patients, 3.3% experienced recurrence and 4.2% died in-hospital. The mean direct medical costs amounted to $4,195/ person, with the greatest expenses for hospitalization and antibiotics. The in-hospital mortality and total medical costs were higher in combined antibiotics therapy than monotherapy (p < 0.05). Charlson’s comorbidity index ≥ 3, standardized early warning scoring ≥ 4, sub-fascia infections and combined initial therapy, were all found to be associated with higher mortality. @*Conclusions@#Korean patients with community-onset cSSSI suffer from considerable clinical and economic burden. Efforts should be made to reduce this burden through appropriate initial treatment.

Hospital-based Influenza Morbidity and Mortality (HIMM) Surveillance for A/H7N9 Influenza Virus Infection in Returning Travelers

Since 2013, the Hospital-based Influenza Morbidity and Mortality (HIMM) surveillance system began a H7N9 influenza surveillance scheme for returning travelers in addition to pre-existing emergency room (ER)-based influenza-like illness (ILI) surveillance and severe acute respiratory infection (SARI) surveillance. Although limited to eastern China, avian A/H7N9 influenza virus is considered to have the highest pandemic potential among currently circulating influenza viruses. During the study period between October 1st, 2013 and April 30th, 2016, 11 cases presented with ILI within seven days of travel return. These patients visited China, Hong Kong, or neighboring Southeast Asian countries, but none of them visited a livestock market. Seasonal influenza virus (54.5%, 6 among 11) was the most common cause of ILI among returning travelers, and avian A/H7N9 influenza virus was not detected during the study period.

Immunogenicity and Safety of Trivalent Inactivated Influenza Vaccine: A Randomized, Double-Blind, Multi-Center, Phase 3 Clinical Trial in a Vaccine-Limited Country

Influenza vaccines are the primary method for controlling influenza and its complications. This study was conducted as a phase 3, randomized, double-blind, controlled, multi-center trial at seven university hospitals to evaluate the immunogenicity and safety of an inactivated, split, trivalent influenza vaccine (GC501, Green Cross Corporation, Yongin, Korea), which was newly manufactured in Korea in 2008. Between September 21 and 26, a total of 329 healthy subjects were recruited for the immunogenicity analysis, while 976 subjects were enrolled for the safety analysis. The GC501 vaccine met both FDA and EMEA criteria with > or = 80% of subjects achieving post-vaccination titers > or = 40 for all three subtypes, even in the elderly. The vaccine was well tolerated with only mild systemic and local adverse events. In summary, GC501 showed excellent immunogenicity and a good safety profile in both young adults and the elderly. The licensure of GC501 might be an important basis in preparation for the future influenza pandemic.

Susceptibility of Clinical Isolates of Acinetobacter baumannii and Pseudomonas aeruginosa to Colistin and Polymyxin B in Korea / 감염과화학요법

BACKGROUND: The emergence of multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa has become a major problem. The use of nontraditional agents such as colistin and polymyxin B have been tried. The purpose of this study was to evaluate the colistin and polymyxin B susceptibility of A. baumannii and P. aeruginosa isolates in Korea. MATERIALS AND METHODS: According to susceptibility of ceftazidime and imipenem, selected 93 isolates of A. baumannii and 99 isolates of P. aeruginosa were collected from 5 university hospitals in Korea. Susceptibility to colistin and polymyxin B was tested using the reference broth microdilution method. RESULTS: The rates of other beta-lactams, aminoglycosides, and ciprofloxacin susceptibility were high (58-100%, 50-100%, and 75-100%, respectively) in ceftazidime- and imipenem-susceptible isolates but were low (< or =31%, < or =47%, and < or =18%, respectively) in ceftazidime- or imipenem-resistant isolates (P<0.05). Colistin and polymyxin B displayed a nearly identical spectrum of activity, exhibiting excellent potency against A. baumannii (MIC50/90, 1/2 microgram/mL) and P. aeruginosa (MIC50/90, 1/1 microgram/mL). Only one of the A. baumannii isolates was resistant to colistin (MIC, 4 microgram/mL), but the isolate was susceptible to polymyxin B (MIC, 2 microgram/mL). CONCLUSION: In Korea, no A. baumannii and P. aeruginosa isolates were resistant to both colistin and polymyxin B. These data suggested that polymyxins may be alternative drugs for multidrug-resistant A. baumannii and P. aeruginosa isolates.

Susceptibility of Clinical Isolates of Acinetobacter baumannii and Pseudomonas aeruginosa to Colistin and Polymyxin B in Korea / 감염과화학요법

BACKGROUND: The emergence of multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa has become a major problem. The use of nontraditional agents such as colistin and polymyxin B have been tried. The purpose of this study was to evaluate the colistin and polymyxin B susceptibility of A. baumannii and P. aeruginosa isolates in Korea. MATERIALS AND METHODS: According to susceptibility of ceftazidime and imipenem, selected 93 isolates of A. baumannii and 99 isolates of P. aeruginosa were collected from 5 university hospitals in Korea. Susceptibility to colistin and polymyxin B was tested using the reference broth microdilution method. RESULTS: The rates of other beta-lactams, aminoglycosides, and ciprofloxacin susceptibility were high (58-100%, 50-100%, and 75-100%, respectively) in ceftazidime- and imipenem-susceptible isolates but were low (< or =31%, < or =47%, and < or =18%, respectively) in ceftazidime- or imipenem-resistant isolates (P<0.05). Colistin and polymyxin B displayed a nearly identical spectrum of activity, exhibiting excellent potency against A. baumannii (MIC50/90, 1/2 microgram/mL) and P. aeruginosa (MIC50/90, 1/1 microgram/mL). Only one of the A. baumannii isolates was resistant to colistin (MIC, 4 microgram/mL), but the isolate was susceptible to polymyxin B (MIC, 2 microgram/mL). CONCLUSION: In Korea, no A. baumannii and P. aeruginosa isolates were resistant to both colistin and polymyxin B. These data suggested that polymyxins may be alternative drugs for multidrug-resistant A. baumannii and P. aeruginosa isolates.

Atypical Pathogens as Etiologic Agents in Hospitalized Patients with Community-Acquired Pneumonia in Korea: A Prospective Multi-Center Study

Local epidemiologic data on the etiologies of patients hospitalized with community-acquired pneumonia (CAP) is needed to develop guidelines for clinical practice. This study was conducted prospectively to determine the proportion of atypical bacterial pathogens in adults patients hospitalized with CAP in Korea between October 2001 and December 2002. Microbiological diagnosis was determined by serology for antibodies to Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella pneu-mophila. Nucleic acid of M. pneumoniae and C. pneumoniae in respiratory samples and Legionella antigen in urine samples were detected. The study population consisted of 126 patients (71 males, 55 females), averaging 54.6 yr (SD+/-17.8), whose paired sera were available. An etiologic diagnosis for atypical pathogens was made in 18 patients (14.3%): C. pneumoniae 9 (7.1%), M. pneumoniae 8 (6.3%), and L. pneumophila 3 patients (2.4%). Streptococcus preumoniae and other typical pathogens were isolated from 36 patients (28.6%). Of 126 patients, 16 (12.7%) were admitted to intensive care unit and atypical pathogens were identified in 5 patients (31.3%). Initial clinical features of patients with pneumonia due to atypical, typical or undetermined pathogens were indistinguishable. We conclude that atypical pathogens should be seriously considered in hospitalized patients with CAP, when initiating empiric treatment in Korea.

A 5-year review of clinical characteristics and mortality of burn patients with candidemia in a tertiary burn center / 대한내과학회지

BACKGROUND: Nosocomial candidemia is one of the most common blood-stream infection and associated with a high fatality rate in burn patients. To determine the clinical characteristics, strains of Candida species and to identify contributing factors to death, we analyzed severely burned patients with candidemia. METHODS: 60 cases with candidemia were reviewed retrospectively from January 1999 to December 2003 at a tertiary burn center in Korea. Candidemia was defined as at least one blood culture that grew Candida organisms. RESULTS: Burn size of all patients were 46+/-20.9% of total body surface area burn and overall mortality was 41.7%. 97 strains of Candida species from 60 cases were isolated. Candida albicans was the most frequently isolated species (53.6%), followed by C. tropicalis (20.6%), C. glabrata (15.5%) and C. parapsilosis (10.3%). Among various predisposing factors for candidemia, significant factors associated with death were endotracheal tube insertion or tracheostomy, mechanical ventilation, the use of vasoactive agents, arterial catheterization and nasogastric tube insertion in univariate analysis, but significant independent factors for mortality were mechanical ventilation (OR=26.63, 95% CI; 1.60, 444.18, p=0.022) and the use of vasoactive agents (OR=23.18, 95% CI; 2.80, 192.35, p=0.004) in multivariate analysis. Among 59 patients indwelling central venous catheters, only 24 patients (40.7%) received antifungal therapy with catheter removal while 19 patients (32.2%) had antifungal therapy without catheter removal. CONCLUSIONS: Clinical severity, such as mechanical ventilation or vasoactive agents dependencies, may contribute to high fatality in severely burned patients with candidemia.

Clinical Characteristics in Patients with Vancomycin-Resistant Enterococci Colonization or Infection during 5 years in a Private General Hospital / 대한구급학회지

BACKGROUND: Vancomycin-resistant enterococci (VRE) is increasing rapidly through the world and is now a major cause of nosocomial infection. The transmission dynamics and factors contributing their dissemination are complex. We conducted a study to investigate clinical characteristics in patients with VRE colonization or infection during recent 5 years. METHODS: 154 cases that had the VRE infection or colonization from January 1, 2000 to April, 2004, were reviewed. We analyzed the risk factors of VRE infection and colonization and also compared various parameters contributing their dissemination between burn and non-burn patients with VRE. RESULTS: Total 212 strains of VRE were isolated from 154 patients. Of 212 strains of VRE, Enterococcus faecium (178 strains, 83.9%) were most common and followed by E. casseliflavus (28 strains, 13.2%), E. faecalis (5 strains, 2.4%) and E. gallinaum (1 strains, 0.5%). The most common place of VRE isolation was in burn intensive care unit (ICU), 95 cases (61.7%); 27 cases (17.5%) in general wards; 17 cases (11.0%) in surgical ICU; 15 cases (9.7%) in medical ICU. Compared with patients with VRE colonization, patients with VRE infection had older age, higher APACHE II scores and high death rate significantly. Then, VRE colonization were more common in burn patients while VRE infection were more common in non-burn patients. CONCLUSIONS: The findings from this study suggest that VRE infection are not uncommon among hospitalized patients. More strict infection control, close surveillance and judicious use of antibiotics may be warranted to prevent infection and transmission of VRE.

A Case of Disseminated Coccidioidomycosis Involving Lung and Skin in Patient with Diabetes Mellitus and Iatrogenic Cushings Syndrome / 결핵및호흡기질환

Coccidioidomycosis is caused by a dimorphous fungus, Coccidioides, which consists of two species, C. immitis and C. posadasii. Although these organisms are genetically distinct and do not exchange DNA, they appear identical phenotypically and the disease or immune response to the organisms is also identical. Coccidioides grows as a mycelium in the soil and is mainly found in Southwestern United States, northwestern Mexico, and Argentina. An infection usually results from inhaling the spores of the fungus in an endemic area. Patients with a localized infection and no risk factors for complications often require only a periodic reassessment to demonstrate the resolution of the self-limited process. However, patients with extensive spread of infection or high risk of complications as a result of immunosuppression or other preexisting factors require a variety of treatment strategies such as antifungal therapy, surgical debridement, or both. Korea is not endemic area of a coccidioidomycosis. We report a case of disseminated coccidioidomycosis involving the lung and skin, which was detected incidentally after sunburn in a 69 year-old Korean male with diabetes mellitus and iatrogenic Cushings syndrome, with a review of the relevant literature.

Preventive Efficacy of Influenza Vaccination against to Influenza-like Illness among Eldery / 한국역학회지

BACKGROUND: Influenza is a highly infectious viral illness. The epidemics of influenza occur from the late fall to the early spring nearly every year and are responsible for several hundred thousand death per year all over the world. Influenza vaccine is the primary method for preventing influenza and its more severe complications. The efficacy of influenza vaccination have been well known in developed countries. The influenza vaccination has been recommended as one of the tentative immunization schedule for indicated persons since 1997 in Korea. But there are still no available data about them, even though nearly 5 - 8 million doses of influenza vaccine were used in a winter season. PURPOSE: To assess the clinical efficacy of influenza vaccine against influenza-like illness(ILI) among Korean elderly(age over 65). METHODS: Primary study design - a prospective field trial. Study subjects and method - We prospectively observed the 1,488 vaccinee and 1,425 non-vaccinee in a community(Nonsan city) from November 1 1998 to March 31 1999. The vaccinee were those who randomly selected 100-200 per 13 sub-region(Myon) in Nonsan city, and the non-vaccinee were those who had not vaccinated until January 1999 among the Nonsan city elderly cohort. This cohort was consisted of 5,787 elderly(over 1/3 of total elderly population) who had ever visited the community health center or 13 public health offices in Nonsan city in 1998. We followed up these two groups two times-in January and April 1999 - by telephone survey. The questionnaire included the questions about the health behaviors, medical history, socioeconomic condition, medical security type, physical function status, medical facility utilization in the season, symptom and signs of influenza-like illness, number and type of the flu, hospitalization or not. We did throat swap to isolate the virus of 490 patient who had influenza -like symptoms in the same period. RESULTS: Influenza vaccination was significantly reduced the incidence of influenza -like illness(fever or chilling sensation and cough or sore throat) in the vaccinated. The preventive effect of influenza-like illness among influenza risk group was about 32%(95% CI, 20%-44%). The illness duration of main symptoms of influenza-like illness(fever, cough) was significantly shorter in the vaccinee. The consistency of the survey was noted quite high from the analysis of the result of test-retest(104 person). CONCLUSION: Influenza vaccination significantly reduced the incidence of influenza-like illness(32%) among elderly.

Study on the Infection Due to VanA Type Vancomycin-resistant Enterococci / 감염

BACKGROUND: Vancomcyin-resistant enterococci(VRE) have become one of major nosocomial pathogens in USA and Europe since 1986. In Korea, only a few cases of VRE infection were reported until now. We investigated the rate of vancomycin resistance among clinical enterococcal isolates, characterized the genotypes of VRE isolates by using polymerase chain reaction (PCR), and analyzed the molecular relatedness of those isolates by using pulsed field gel electrophoresis(PFGE) technique. METHODS: Standard disk diffusion test, break point screening test and measurement of minimal inhibitory concentraion(MIC) were used for identification of VRE. Duplex vanA-vanB PCR for genotyping of vancomcyin resistance, and PFGE for molecular epidemiologic analysis were performed. RESULTS: Incidence of VRE among clinical enterococcal isolates during the study period(July, 1995~June,1996) was 1.0%(2/202). Two strains among 68 suspicious VRE, which were identified by disk diffusion method, were confirmed as true VRE by break point screening and MIC test. MIC of both VRE isolates were same(vancomycin : 512microgram/ml, teicoplanin 64microgram/ ml). Both VRE isolates were confirmed as vanA genotypes by duplex PCR and identical clones by PFGE and dendrogram analysis. CONCLUSION: Frequency of VRE among clinical enterococcal isolates is still very low(1%) in this hospital. We reported two VRE isolates which were confirmed by MIC determination and PCR genotyping. Judicious surveillance study of VRE and strict control of vancomycin usage are required to prevent the emergence and dissemination of VRE.

A case mycoplasma pneumoniae pneumonia with acute respiratory distress syndrome (ARDS) / 대한내과학회지

Pneumonia caused by Mycoplasma pneumoniae is manifested as a mild and self-limited. However, several overwhelming cases have been reported. Recently, we experienced a case of M. pneumoniae pneumonia that progressed into ARDS in a 68-year old man who was admitted because of fever and erythema multiforme on whole body. On admission, serum cold agglutinins and anti-mycoplasma Ab were negative. Lobar consolidation was visible at initial chest X-ray. But, bilateral infiltration was noted at follow-up chest X-ray and his condition was aggravated to ARDS. Anti-mycoplasma Ab was elevated up to 1:640. He was treated with roxithromycin, prednisolone and mechanical ventilator in ICU for 2 weeks. And after this, his clinical condition was recovered completely.

A Sporadic Case of Fulminant Meningococcemia / 감염

Meningococcal disease is still a major cause of sporadic endemic and epidemic diseases throughout the world. In Korea meningococcal epidemics have been documented occasionally in military recruits, where as sporadic cases rarely reported. Meningococcemia represents a part of the various spectrum of the illness, and its clinical manifestations varied from mild fever to fulminant catastrophic events within a few hours after onset of symptoms. We experienced a case of a sporadic fulminant meningococcemia presenting with fever, petechiae, and purpura. The patient was a 21-year old female nursing school student. She had high fever, petechiae and purpura on both lower extremities, which spreaded to the whole body with peripheral gangrene during her admission days. Despite the treatment with ceftriaxone and chloramphenicol, refractory shock developed. She expired on the third day after onset of symptoms. Neisseria meningitidis was cultured from the blood after she died.

A Case of Fatal Nosocomial Legionnaires' Disease by Legionella pneumophila Serogroup 1 / 감염

Nosocomial Legionnaires' disease has often been documented to occur in immunocompromised patients and to be severe, potentially fatal, pneumonia. We report a case of fatal nosocomial Legionnaires' disease developed shortly after steroid pulse therapy. A 39-year old woman with systemic lupus erythematosus was admitted via emergency room due to generalized edema and gross hematuria. Under the diagnosis of lupus nephritis, she was given intravenous steroid pulse therapy for 3 days and then maintained with oral prednisolone. On the 7th day of admission the patient's conditions got worse with progression to acute renal failure and respiratory difficulty. On the 10th day of admission when she was started on hemodialysis, chestradiograph showed newly developed multifocal mass-like consolidations on both lung fields. In spite of empirical therapy with roxithromycin and rifampin, the consolidations were aggravated and rapidly extended to both whole lung fields. On the 15th day of admission she was mechanically ventilated due to respiratory failure, but died of hypoxia and shock on the 19th day. Later, a legionella species was isolated from the tracheal aspirates and identified as L. pneumophila serogroup 1. We also detected L. pneumophila from the tracheal aspirates by duplex PCR which amplified both 5S rRNA and mip genes of L. pneumophila.

Epidemiologic study of nosocomial candidiasis by restriction fragment analysis (RFA) and southern hybridization / 대한내과학회지

BACKGROUND: Candida species are not only the leading cause of nosocomial fungal infections but also the important cause of infections in the immunocompromised hosts. Epidemiologic study of nosocomial candidiasis has been difficult because of the lack of a reliable typing system. We performed molecular epidemiologic study by using RFA and Southem hybridization for typing of candida isolates from patiients. METHODS: A total of 27 candida isolates from 19 immunocompromised patients were studied. Morphotyping and biotyping were done by germ tube test and API 20C system, respectively. Candidial chromosomal DNA was extracted, digested with EcoRI, HindalII and RFA was done. Southem hybridization of chromosomal DNA was also done with digoxigen-labelled Candial albicans-specific DNA probe. RESULTS: The time-period of development of oral candidiasis after admission was 5-14 days (mean: 8 days). C.albicans was the most common species (19), followed by C tropiadis (2), C glabn#zta (2), C.paratropicalis (2), and C parapsilosis (1). The subtypes of Candida species by RFA of chromosomal DNA were C. albieans, 12 types , C tropicalis, 2 types, C glabrata, 2 types ; C.parapsilasis, 1 type ; C. paratropicalis, 1 type. For 7 (87.5%) of 8 patients, RFA pattern of one isolate was identical to that of the other isolates. CONCLUSION: RFA of candidial chromosomal DNA results were obtainable within days. RFA showed high reproducibility, typeability and good discrimination power between isolates, provided a robust system that may be used rapidly to identify outbreaks of nosocomial candidiasis.

Diagnosis of acute Hantaan virus infection by IgG avidity assay / 대한내과학회지

OBJECTIVE: The golden standard of serodiagnosis of HFRS is IFA(indirect immunofluorescence antibody test). However, positive IFA for IgG antibody does not always correlate with current infection because IFA may be positive due to past exposure to Hantaan virus such as subclincal infection or due to vaccination in endemic area. So supplementary diagnostic method is needed to diagnosis of HFRS with more accuracy. METHODS: In this study, the usefulness of IgG avidity assay with 8 mole/l urea in diagnosis of HFRS was investigated. Serum samples from 45 patients with acute phase HFRS and 79 residents of endemic area, who had HFRS antibody were tested for IgG avidity. RESULTS: The distribution of IgG avidity index of HFRS antibody was different acute phase of HFRS patients from endemic area residents(p<0.001). Patients with acute phase HFRS exhibited lower avidity of Hantaan virus-specific IgG (mode of 64 of avidity index), in contrast endemic area resident had a higher avidity (mode of 4 of avidity index). CONCLUSION: The IgG avidity assay should assist in the diagnosis of acute phase HFRS and may be used to identify recent infection and past exposure to Hantaan virus.

A Prospective Study on the Incidence of Intravenous Catheter-related Complication / 병원감염관리

BACKGROUND: Intravenous catheter-related complication among the hospitalized patients has been increasing recently in Korea, since many hospitals has tried to save expenses by replacing the foreign-made catheter with domestic-made intravenous catheter. We studied the incidence rate of catheter-related complication and compared the incidence of catheter-related complication between domestic-made and foreign-made ones. We also studied to elucidate whether the morphologic characteristics of the intravenous catheter will effect the incidence of catheter-related complication. METHOD: From July 1 to Sept 30, 1998, we surveyed the incidence rate of intravenous catheter-related complication among the hospitalized patients in the wards of Medicine. Surgery, Obstetric, and Neonatal Intensive Care Unit in Guro Hospital, Korea University Medical center. We also compared the incidence of complication between domestic-made catheter (catheter A) and foreign-made catheter (catheter B) of three different gages (24G, 22G and 18G). The morphologic characteristics of intravenous catheters has been studied by electron microscopy. RESULT: Complication associated with use of intravenous catheter had been occurred 263 out of 459 cases (57.3%), among those cases, non-infectious complication and infectious complication were 173 cases (37.7%) and 90 cases (19.6%), respectively. Totally, catheter A group showed higher complication than catheter B group [62.0% (160/258) vs 51.2% (103/201), P=.021]. Analysis on the incidence rate of complication according to the products did not show significant differences in the noninfectious complication in every gage groups. However the infectious complication occurred higher in the domestic-made catheter A group than among the foreign-made catheter B group [(24G: 6% vs 0%, P=.026), (22G: 25.6% vs 9.6%, P=.001), (18G: 36.8% vs 13.4%, P=.002)]. Duration of catheter life did not show the difference between catheter A group and catheter B group [48.5hrs vs 50.3hrs, P=.474]. The analysis on risk factors for complication showed that catheter A group is highly related (odd ratio 1.85). The morphologic analysis of the catheter by using electron microscopy showed that the angles in the tip of the introducing needle of catheter Aand catheter Bare 60degrees and 45degrees , respectively, and the bevel between introducing needle and catheter sheath are 50degrees and 27degrees, respectively. CONCLUSION: There was a higher incidence rate of complication related to domestic-made catheter usage, which might influence increasing the period of the hospitalization and the expenses due to the complication. The study of cost effectiveness analysis needs to be performed regarding intravenous catheter-related complication. Morphologically, catheter A showed more blunt angle in the tip and transition area of the introducing needle than the angle of catheter B, which is considered to influence the higher complication incidence. It needs to improve the quality of domestic-made intravenous catheter.

Rectal Surveillance Culture of Vancomycin-resistant Enterococci (VRE) Colonization among Patients Hospitalized in the Intensive Care Unit (ICU) / 감염

BACKGROUND: VRE (vancomycin-resistant enterococci) have been an important nosocomial pathogen in the United States in the 1990s. VRE are usually multidrug-resistant and currently there is no effective antimicrobial agent for the treatment of such organisms. Recently, VRE have become an emerging nosocomial pathogen in Korea, but there have been few studies on the epidemiologic investigation of the infection or colonization of VRE among hospitalized patients with high risk factors. The purpose of this study was to determine the prevalence of rectal colonization of VRE among patients hospitalized in the intensive care unit (ICU), to study the risk factors for nosocomial acquisition of VRE, and to obtain the baseline data for controlling the spread of VRE infection within the hospital. METHODS: Between August 1 and October 12 (10 weeks) 1998, a prospective surveillance study was conducted in the ICU at Korea University, Guro Hospital. Surveillance rectal swab cultures for detecting VRE were obtained at weekly intervals among 93 patients admitted to the ICU during the study period. To obtain the VRE, rectal swab cultures were performed on Enterococcosel agar (BBL Microbiology Systems, Cockeysville, Md., USA) containing 6 microgram/mL of vancomycin. Minimal inhibitory concentrations (MICs) of vancomycin and teicoplanin were determined by agar dilution method. For the genotyping of isolated VRE, detection of vanA, vanB, vanC1 and vanC2 gene by polymerase chain reaction was done. Patients harboring VRE were compared to patients who were not colonized with this organism to identify the risk factors associated with rectal colonization. RESULTS: The rectal colonization rate of VRE was 23.7% (22/93 patients), but no patients had VRE infection during the study period. Twenty-six strains of VRE, which were isolated from 22 patients, included 2 E. faecium, 18 E. gallinarum and 6 E. casseliflavus isolates. Two vancomycin-resistant E. faecium (VREF) isolates were vanA genotype. All E. gallinarum, and all E. casseliflavus isolates demonstrated vanC1 and vanC2 genotype, respectively. Risk factors for rectal colonization of VRE included diabetes, catheterization of arterial and central venous lines, and vancomycin usage. CONCLUSION: This study demonstrated the low rectal colonization rate of clinically significant VREF (2.2%:2/93 patients) isolates among patients admitted to the ICU. This study suggests that maintaining HICPAC guidelines, restricted vancomycin usage and periodic surveillance in patients with high risk factors are important in preventing the emergence and spread of VRE infection among ICU patients in a university- affiliated hospital.

Infection Control Activity in Hallym University Medical Center / 병원감염관리

No Abstract available.

Detection of Mycobacterium tuberculosis from Peripheral Blood of Patients with Tuberculosis by Polymerase Chain Reaction / 감염

BACKGROUND: Conventional diagnostic methods of pulmonary tuberculosis, such as acid-fast bacilli staining and culture of sputum, have the disadvantages of low sensitivity and long incubation period, respectively. The diagnosis of extrapulmonary tuberculosis needs invasive procedures. We investigated the value of PCR-based detection of Mycobacterium tuberculosis from peripheral blood mononuclear cells for diagnosis of pulmonary or extrapulmonary tuberculosis. METHODS: The peripheral blood mononuclear cells were collected from 23 patients with pulmonary tuber-culosis( n=10) and extrapulmonary tuberculosis(n=13), in-cluding miliary tuberculosis(n=5), and 10 healthy indi-viduals as negative controls. A pair of primers was used to produce a 314 bp amplification product from the insertion element IS6110, which is specific for M. tuberculosis. PCR products were detected by agarose gel electrophoresis and southern hybridization using a IS6110 specific oligoprobe. RESULTS: Eight out of ten with pulmonary tuberculo-sis and 9 out of 13 patients with extrapulmonary tuber-culosis showed positive results, yielding 73.9%(17/23) positivity on PCR assay. All five patients with miliary tuberculosis were positive. None of the healthy indivi-duals showed positive results. CONCLUSION: The PCR assay for M. tuberculosis from peripheral blood seems to be useful for diagnosis of tuberculosis, especially miliary tuberculosis. Further studies about the value of the PCR assay in monitoring treatment response are needed.