Colonization of nosocomial pathogens on computer keyboards in patient care areas.

Objective: Nosocomial infections are an important cause of morbidity and mortality in hospitalized patients. The role of the hospital environment as a reservoir of nosocomial pathogens is controversial and has not been thoroughly investigated. In the past years at our institution, computers have been widely used in patient care areas, including general wards and intensive care units. There are studies which show that inanimate objects in the hospital environment constitute reservoirs of nosocomial pathogens. Hence, the study is designed to determine whether computer keyboards in the patient care areas in the Department of Medicine, Siriraj Hospital were reservoirs of nosocomial pathogens. Methods: Twenty-six computer keyboards from general medical wards (20) and intensive care units (6) and 26 computer keyboards from secretarial offices were studied from August to September 2003. All the keyboards were cultured for aerobic pathogens by cotton swab technique. Results: The overall colonization rate of pathogens on the keyboards was 96.2% from patient care areas and 92.3% from the offices (p=1). The colonization rates of non-fermentative gram negative bacilli on the keyboards located in the patient care areas and the offices were 11.5% and 0%, respectively (p=0.24). However, if the fungal isolate was considered a potential pathogen, its colonization rate on the keyboard was 4.3% in the patient care areas compared with 1.5 % in the offices (p=0.03). Conclusion: There was a trend in finding potential pathogenic organisms more often from the computer keyboards located in the patient care areas than from those in the offices. The computer keyboards located in the patient care areas should be periodically cleaned.

Epidemiology of acinetobacter baumannii infections in Siriraj Hospital 2002.

A.baumannii is a pathogen causing hospital-acquired infections. A.baumanii infections are difficult to treat because this organism is usually multi-drug resistant. Objective: To determine the epidemiology of A. baumannii infections in Siriraj Hospital in 2002. Methods: From January to December 2002, we prospectively studied hospitalized patients in Siriraj Hospital who had A.baumannii isolated from their clinical specimens. Results: During the study period, A.baumannii was isolated from clinical specimens of 208 cases. Eighty-six patients (41.3%) had A. baumannii infections whereas 122 patients (58.7%) had A. baumannii colonization. Of the 86 patients with A.baumannii infections, 54.7% were males and 45.3% were females. The mean age of patients was 56.1 years. Ninety-eight percent of the infections were hospital-acquired. The patients developed infection after an average of 26 days of hospitalization. Fifty-two percent of the patients were in the general wards, whereas 48% of them were in ICU. The common sites of infection were respiratory tract and skin and soft tissues. Factors associated with A.baumannii infection were identified in 98.8% of the patients. The most common factors were prior use of antibiotics especially ceftazidime and indwelling medical devices. The susceptibility of A.baumannii to carbapenems, aminoglycosides, beta-lactam/ beta-lactamase inhibitors, co-trimoxazole, fluoroquinolone, 4th generation cephalosporins and 3rd generation cephalosporins was 32%, 16%, 12 %, 9%, 7%, 4% and 3%, respectively. Fifty-seven percent of A.baumannii isolates were resistant to all antimicrobials currently available in Thailand. The overall mortality rate of the patients infected with A.baumannii was 54.7%. Conclusion: Most A.baumannii infections in Siriraj were hospital-acquired. The most common site of infection was the respiratory tract. The majority of A.baumannii isolates was multi-drug resistant. The mortality rate of A.baumannii infections was high.

Comparison of outcomes and efficiency between drawing two blood samples and three blood samples for culture.

Objective: Since the Department of Microbiology, Faculty of Medicine Siriraj Hospital recommends that three blood samples or at least two blood samples should be sent to the laboratory for culture, the study is designed to determine the outcomes and efficiency between drawing two blood samples and three blood samples for culture. Methods: The results of all blood samples sent to the microbiology laboratory for culture from March 2002 to February 2003 were analyzed. Results: 782 blood cultures had three blood samples, and 10,264 had two blood samples. The overall positive culture rates of the two blood samples and three blood samples were 14.1% and 18.5%, respectively (p<0.001). The positive culture rates for pathogenic organisms of the two blood samples and three blood samples were 10.4% and 15%, respectively (p<0.001). The types of organisms recovered from both groups were similar. Drawing three blood samples was not relatively more efficient due to its higher cost with minimal significant benefit. Conclusion: For general patients suspected of having bacteremia, drawing two blood samples should be sufficient for culture, and it is more efficient than drawing three blood samples.

Epidemiology of extended-spectrum beta-lactamase producing gram-negative bacilli at Siriraj Hospital, Thailand, 2003.

A cross-sectional study was conducted from August to September, 2003 to determine the prevalence and risk factors in acquiring extended-spectrum beta-lactamase (ESBL) producing gram-negative bacilli (GNB) in patients admitted to Siriraj Hospital and the outcomes of these infections. Of 346 isolates of gram-negative bacteria in 249 patients, 102 isolates from 87 patients were colonization only, but 244 isolates from 162 patients were infections. The common GNB were Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii and Enterobacter cloacae. The overall prevalence of ESBL producers was 30.1%. K. pneumoniae had a very high prevalence of ESBL producers (56.9%). The urinary tract was the most common site for ESBL- producing GNB infections. Nosocomial infections, duration from admission to infection, peripheral line, urinary catheterization, nasogastric tube insertion and previous use of beta-lactams, cephalosporins and fluoroquinolones were associated with acquiring ESBL-producing GNB infections. ESBL-producing GNB were significantly more resistant to antimicrobial agents. More than 80% of ESBL-producing GNB were susceptible to carbapenems. Mortality in patients infected with ESBL-producing GNB (41.3%) was significantly higher than those infected with non- ESBL-producing GNB (19.8%).

Alveolar echinococcosis : An unusual liver mass in a Thai Patient.

We report herein the case of a 40-year-old Thai woman who developed a hepatic tumor like lesion suspected to be cholangiocarcinoma. The patient underwent hepatic surgery and the heptatic mass was sent for a histopathological examination. The gross section of the hepatic mass demonstrated alveolar echinococcosis, which showed the specfic rostellar hooks of Echinococcus multilocularis metacestodes. As our patient had been record, it was highly likely that this alveolar echinococcosis had been contacted foreign country. The laboratory tests showed no eosinophilia. After surgery, the patient was treated with albendazole which led to improvement of went of the disease. To our knowledge this is the first described case of alveolar echinococcosis (AE), as the diagnosis of this disease is usually found in the to chronic phase. This study also reviewed comparative echinococcosis and previously reported cases in Thailand. The alveolar echinococcosis is outlined with respect to this helminthic infection a long with recent contributions in areas of parasitology, pathology, diagnosis and transmission.

Eosinophilic meningitis due to Angiostrongylus cantonensis.

We report a 23 year old female who presented with a history of headache. She was admitted to a hospital in Nakornrachasrima province. Eosinophilic meningitis was diagnosed. However, releasing pressure of cerebrospinal fluid (CSF) by lumbar puncture, supportive and symptomatic treatment were performed resulting in appropriate treatment. The patient was referred to Siriraj Hospital due to the persisted headache. Multidisciplinary investigation such as imaging modalities, cytology and serological test for specific antibodies were carried out. Antibody against an A. cantonensis-specific 31-kDa antigen was detected in the serum sample obtained from this patient. In conclusion, A. cantonensis is the possible causative agent of headache in this patient.

Efficiency of the glutaraldehyde test strip for monitoring the concentration of glutaraldehyde in reused solutions for disinfecting endoscopes.

BACKGROUND: Glutaraldehyde has been widely used for low-temperature disinfection of endoscopes. The current practice at Siriraj Hospital is to change the glutaraldehyde solution every 21 days or when the solution appears turbid. The disadvantages of this practice include inadequate disinfection of endoscopes if the concentration of glutaraldehyde in a reused solution is insufficient or wasted if the discarded solution is still active. OBJECTIVE: To determine the efficiency of a glutaraldehyde test strip (GTS) in monitoring the amount of glutaraldehyde in a reused solution for disinfecting endoscopes. METHOD: Reused glutaraldehyde solutions for disinfecting bronchoscopes, gastroscopes and colonoscopes were tested for the concentration of glutaraldehyde with a GTS thrice weekly for the first week and then every working day up to 56 days. If the GTS indicated a concentration of glutaraldehyde > or = 1.8 per cent after 21 days, 5 ml of the solution was taken to the laboratory to determine its mycobactericidal activity. RESULTS: All samples of the reused glutaraldehyde solution up to 56 days with a concentration of > or = 1.8 per cent glutaraldehyde on GTS from testings showed mycobactericidal activity. If the glutaraldehyde solution was reused for up to 28, 42 or 56 days, it could save 9,603; 22,813 and 29,415 baht per year respectively for the gastroscopy and colonoscopy units. The corresponding figures were -949; 2,726 and 4,564 baht per year for the bronchoscopy unit. It is estimated that up to 400,000 baht per year could be saved by adopting the strategy of GTS monitoring in all endoscopy units at Siriraj Hospital. CONCLUSION: The current strategy of discarding reused glutaraldehyde solution in the gastroscopy, colonoscopy and bronchoscopy units at Siriraj Hospital may be inappropriate since the reused solution is still mycobactericidal for up to 56 days.