Clinical Features Associated with Blood Cultures According to the Use of Antimicrobial Agents Prior to Blood Collection / 대한임상미생물학회지

BACKGROUND: Previous antibiotic exposure may inhibit the growth of microorganisms in blood culture bottles. The authors investigated the frequency of previous antibiotic usage and analyzed the relationships among antibiotic usage, microbiological culture results and mortality of sepsis patients. METHODS: From April to May 2011, all blood cultures requested from inpatients were analyzed according to the admitted ward and antibiotic prescription records. The BacT/Alert 3D system (bioMerieux Inc.) was used with a standard bottle (SA, SN) for blood culture. RESULTS: Of 900 inpatients, 48% had been receiving antimicrobial agents when blood cultures were ordered. This group had a significantly higher mortality rate (36.2%) compared to the patients who had not received antibiotics (11.1%). Gram-negative rod bacteremia (37.1%) and candidemia (100%) resulted in a significantly higher mortality rate compared to Gram-positive cocci bacteremia (16.4%). In the analysis of 21 cases resulting in death, 15 (71.4%) patients died before or on the date when blood culture results were reported. CONCLUSION: Patients who receive antibiotics prior to blood collection may be at a higher risk for mortality. In the present study, Gram-negative rod bacteremia and candidemia cases showed a rapid progression of sepsis as indicated by Gram staining and thus should be regarded seriously.

A Case of Peritonitis Due to Achromobacter xylosoxidans subsp. xylosoxidans in a Patient Undergoing Continuous Ambulatory Peritoneal Dialysis (CAPD) / 대한신장학회지

Bacterial peritonitis is a well-recognized complication of continuous ambulatory peritoneal dialysis (CAPD) in patients with end-stage renal failure. Achromobacter xylosoxidans subsp. xylosoxidans is a catalase and oxidase positive, motile, nonfermentative and gram-negative rod bacterium that is a rare pathogen in humans and has rarely been reported as an opportunistic human pathogen. We present a case of peritonitis due to unusual pathogens, Achromobacter xylosoxidans subsp. xylosoxidans. A 49-year-old diabetic man undergoing CAPD for 90 days developed the first peritonitis due to Achromobacter xylosoxidans subsp. xylosoxidans. A. xylosoxidans was detected from a culture of peritoneal fluid. Susceptible antibiotic treatment was provided.

Two Cases of Pulmonary Infection due to A. xylosoxidans Infection in an Immunocompentent Patient / 결핵및호흡기질환

lcaligenes xylosoxidans is a catalase and oxidase positive, motile, nonfermentative and gram-negative rod bacterium. A. xylosoxidans infection is a rare cause of pulmonary infection and little information concerning treatment is available. The majority of patients that develop A. xylosoxidans infection belong to a high-risk group due to an immunocompromised condition or due to pulmonary cystic fibrosis. We report two rare cases of immunocompentent patients that developed a pulmonary infection due to A. xylosoxidans. A 77-year-old man was admitted with a lung abscess. The patient denied having any prior medical illness. A culture of bronchial washing fluid showed the presence of A. xylosoxidans. Despite appropriate antibiotic treatment, the patient died from acute respiratory distress syndrome (ARDS). Another patient, a 61-year-old man without an underlying disease, was admitted with empyema. Under the condition of a closed thoracostomy, a high fever persisted and the empyema was also aggravated. A. xylosoxidans was detected from a culture of pleural fluid. Susceptible antibiotic treatment was provided and surgical intervention was performed. We report these cases with a review of the literature.