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Medline ® Abstracts for References 3-7

of 'Acinetobacter infection: Epidemiology, microbiology, pathogenesis, clinical features, and diagnosis'

3
TI
Fulminant community-acquired Acinetobacter baumannii pneumonia as a distinct clinical syndrome.
AU
Leung WS, Chu CM, Tsang KY, Lo FH, Lo KF, Ho PL
SO
Chest. 2006;129(1):102.
 
STUDY OBJECTIVES: Acinetobacter baumannii (AB) is an important cause of hospital-acquired pneumonia (HAP), and an uncommon but important cause of community-acquired pneumonia (CAP) with high mortality. To better characterize CAP-AB, we compared its clinical features and outcomes with a control group of HAP-AB patients.
METHODS: This is a retrospective case-control study comparing CAP-AB and HAP-AB patients, which was performed at United Christian Hospital between July 2000 and December 2003.
RESULTS: There were 19 cases of CAP-AB and 74 cases of HAP-AB. When compared with the HAP-AB group, the CAP-AB group had more ever-smokers (84.3% vs 55.4%, respectively; p = 0.031), more COPD patients (63.2% vs 29.7%, respectively; p = 0.014), and fewer median days of hospitalization (HAP-AB group, median, 0 days; CAP-AB group, 0 days [range, 0 to 30 days]; p = 0.049) in the previous year. The CAP-AB group had more patients with positive blood culture findings (31.6% vs 0%, respectively; p<0.001), a higher frequency of ARDS (84.2% vs 17.6%, respectively; p<0.001), and disseminated intravascular coagulation (DIC) (57.9% vs 8.1%, respectively; p<0.001). The median survival time was only 8 days in the CAP-AB group, vs 103 days in the HAP-AB group (p = 0.003). Factors associated with the higher mortality in the CAP-AB group included the presence of AB bacteremia (p = 0.040), platelet count of<120 x 10(9) cells/L (p = 0.026), pH<7.35 on presentation (p = 0.047), and the presence of DIC (p = 0.004).
CONCLUSIONS: CAP-AB appears to be a unique clinical entity with a high incidence of bacteremia, ARDS, DIC, and death, when compared to HAP-AB. Further studies are needed to investigate the mechanism of the fulminant nature of CAP-AB.
AD
Department of Medicine and Geriatrics, United Christian Hospital, Hong Kong SAR, Peoples Republic of China.
PMID
4
TI
Community-acquired bacteremic Acinetobacter pneumonia in tropical Australia is caused by diverse strains of Acinetobacter baumannii, with carriage in the throat in at-risk groups.
AU
Anstey NM, Currie BJ, Hassell M, Palmer D, Dwyer B, Seifert H
SO
J Clin Microbiol. 2002;40(2):685.
 
Acinetobacter isolates from eight subjects with community-acquired Acinetobacter pneumonia (CAAP), a major cause of fatal community-acquired pneumonia in tropical Australia, were phenotypically and genotypically confirmed by pulsed-field gel electrophoresis analysis to be broadly diverse Acinetobacter baumannii strains. Wet-season throat carriage of A. baumannii was found in 10% of community residents with excess levels of alcohol consumption, the major at-risk group for CAAP.
AD
Menzies School of Health Research, Royal Darwin Hospital, Northern Territory Clinical School, Darwin, Northern Territory, Australia. anstey@menzies.edu.au
PMID
5
TI
Epidemiology and infection control implications of Acinetobacter spp. in Hong Kong.
AU
Houang ET, Chu YW, Leung CM, Chu KY, Berlau J, Ng KC, Cheng AF
SO
J Clin Microbiol. 2001;39(1):228.
 
In a previous study, we showed that Acinetobacter genomic DNA group 3 was the most common species among blood culture isolates and was commonly found on superficial carriage sites of the healthy and the sick, which are different findings from those reported in Europe and North America. We used amplified ribosomal DNA restriction analysis and pulsed-field gel electrophoresis to study further the molecular epidemiology of acinetobacters in our region. Over a study period of 6 weeks with 136 consecutive routine clinical isolates (1.33% of all specimens), genomic DNA groups 2 (Acinetobacter baumannii), 3, and 13TU were obtained from 59 of 69 positive patients. There is a significant difference in the specimen sources of the three genomic DNA groups, with group 13TU being significantly associated with the respiratory tract (chi-square exact test, P = 0.0064). Settle plates showed a significantly heavier environmental load from the intensive care unit (ICU) than from the four surgical wards examined (22 of 70 versus 76 of 120 plates with<5 colonies; chi-square test, P<0. 0001). Genomic group 3 accounted for 6 of 12 clusters of possibly related strains among patients, between patients and the ICU environment, and in the ICU environment. Genomic groups 2 and 3 accounted for 21% of the 132 genomically identified isolates recovered from 21 of 41 local vegetables, 53 of 74 fish and meat samples, and 22 of 60 soil samples. Group 13TU was present only in patients' immediate surroundings. The role played by the environment and by human carriage should be evaluated in order to devise a cost-effective infection control program pertinent to our situation of acinetobacter endemicity.
AD
Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin NT, Hong Kong SAR, People's Republic of China. ehouang@cuhk.edu.hk
PMID
6
TI
Severe community-acquired pneumonia due to Acinetobacter baumannii.
AU
Chen MZ, Hsueh PR, Lee LN, Yu CJ, Yang PC, Luh KT
SO
Chest. 2001;120(4):1072.
 
STUDY OBJECTIVES: To investigate the clinical, epidemiologic, and microbiological characteristics of community-acquired pneumonia (CAP) due to Acinetobacter baumannii.
METHODS: Retrospective chart and radiographic reviews of all patients who were admitted to National Taiwan University Hospital from January 1993 to August 1999, fulfilled the criteria for CAP, and had an isolate of A. baumannii from blood or pleural fluid at hospital admission.
RESULTS: Thirteen patients (9 men and 4 women; age range, 37 to 85 years) met the criteria. Conditions associated with the infection included male gender, old age, alcoholism, malignancy, cerebrovascular disease, diabetes mellitus, renal disease, and liver cirrhosis. Eleven patients (85%) acquired the infection during the warmer months of April to October. Twelve patients (92%) had a fulminant course presenting with septic shock and respiratory failure, and 11 patients (85%) needed ventilator support and were treated in an ICU. Six patients (46%) had leukopenia. Lobar consolidations were found in 12 patients (92%), and pleural effusions were present in 4 patients (31%). All patients hadpositive blood culture results, two patients (15%) had positive pleural effusion culture findings, and nine patients (69%) positive sputum culture results. All the isolates were susceptible to imipenem, and most were susceptible to aminoglycosides, ceftazidime, ciprofloxacin, and extended-spectrum penicillins. Eight patients (62%) died. Four of the five survivors were initially treated with combination of a third-generation cephalosporin and an aminoglycoside.
CONCLUSION: A. baumannii should be considered as a possible etiologic agent in community-acquired lobar pneumonia when (1) patients with a fulminant course present during the warmer and more humid months of the year, and (2) patients are younger alcoholics. A good sputum smear, defined as a Gram stain smear of an adequate sputum specimen that comes from the lower respiratory tract and contains>25 leukocytes per high-power (100x) field on microscopic examination, can help early diagnosis and treatment. A combination of a third-generation cephalosporin and an aminoglycoside may be appropriate empirical therapy.
AD
Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
PMID
7
TI
Control of nosocomial infections in an intensive care unit in Guatemala City.
AU
Berg DE, Hershow RC, Ramirez CA, Weinstein RA
SO
Clin Infect Dis. 1995;21(3):588.
 
We tested the effectiveness of specific vs. general infection control interventions in a teaching hospital in Guatemala City. After 3 months of prospective surveillance, we implemented targeted interventions (i.e., modification of respiratory tract care and use of a closed urinary catheter drainage system), an educational program focused on respiratory intervention, and general interventions (i.e., aseptic technique). The rate of nosocomial pneumonia, the most common nosocomial infection, decreased from 33% (41 of 123 patients) before intervention to 16% (21 of 130 patients) after intervention (P = .001). Although the frequency of hand washing increased from 5% to 63% (P<.001), the rates of other types of nosocomial infections did not change significantly. The combination of targeted respiratory intervention and an intense, focused educational campaign reduced the rate of nosocomial pneumonia. General improvements in hygiene and hand washing rates, or even implementation of a closed urinary drainage system without focused education, may not be sufficient to reduce infection rates in intensive care units in developing countries.
AD
Michael Reese Hospital and Medical Center, University of Illinois Abraham Lincoln College of Medicine, Chicago, USA.
PMID