1/1318. Emergence of vancomycin resistance in Staphylococcus aureus. Glycopeptide-Intermediate Staphylococcus aureus Working Group. BACKGROUND: Since the emergence of methicillin-resistant staphylococcus aureus, the glycopeptide vancomycin has been the only uniformly effective treatment for staphylococcal infections. In 1997, two infections due to S. aureus with reduced susceptibility to vancomycin were identified in the united states. methods: We investigated the two patients with infections due to S. aureus with intermediate resistance to glycopeptides, as defined by a minimal inhibitory concentration of vancomycin of 8 to 16 microg per milliliter. To assess the carriage and transmission of these strains of S. aureus, we cultured samples from the patients and their contacts and evaluated the isolates. RESULTS: The first patient was a 59-year-old man in michigan with diabetes mellitus and chronic renal failure. peritonitis due to S. aureus with intermediate resistance to glycopeptides developed after 18 weeks of vancomycin treatment for recurrent methicillin-resistant S. aureus peritonitis associated with dialysis. The removal of the peritoneal catheter plus treatment with rifampin and trimethoprim-sulfamethoxazole eradicated the infection. The second patient was a 66-year-old man with diabetes in new jersey. A bloodstream infection due to S. aureus with intermediate resistance to glycopeptides developed after 18 weeks of vancomycin treatment for recurrent methicillin-resistant S. aureus bacteremia. This infection was eradicated with vancomycin, gentamicin, and rifampin. Both patients died. The glycopeptide-intermediate S. aureus isolates differed by two bands on pulsed-field gel electrophoresis. On electron microscopy, the isolates from the infected patients had thicker extracellular matrixes than control methicillin-resistant S. aureus isolates. No carriage was documented among 177 contacts of the two patients. CONCLUSIONS: The emergence of S. aureus with intermediate resistance to glycopeptides emphasizes the importance of the prudent use of antibiotics, the laboratory capacity to identify resistant strains, and the use of infection-control precautions to prevent transmission. ( info) |
| Miliary tuberculosis is a rare form of tuberculosis in industrialized countries. We report on a 69-year-old woman presenting a sepsis syndrome caused by cryptic miliary tuberculosis clinically mimicking a case of cholecystitis with sepsis. The patient died of a multi-organ failure on day 6 of her hospital stay. ( info) |
3/1318. flavobacterium meningosepticum sepsis in an infant with a diarrheal prodrome. A full term, previously normal 2 1/2-month-old black boy was transferred to our hospital from an outlying facility on hospital day 5 for failure to thrive. Three weeks before transfer, the infant was hospitalized for a diarrheal illness with fever. The baby received 3 days of ceftriaxone empirically and was discharged home after the sepsis evaluation was negative. Mild diarrhea and steady weight loss continued and the baby was readmitted. blood culture done on admission grew flavobacterium meningosepticum, an organism previously described as an uncommon cause of sepsis in neonates and immunocompromised individuals. As it is water-borne, it has been associated with infection via contaminated water. This organism is usually resistant to antibiotics commonly used for empiric treatment. To our knowledge, this is the first reported case of flavobacterium bacteremia associated with a prodromal and concurrent diarrheal illness. ( info) |
4/1318. Central line sepsis in a child due to a previously unidentified mycobacterium. A rapidly growing mycobacterium similar to strains in the present mycobacterium fortuitum complex (M. fortuitum, M. peregrinum, and M. fortuitum third biovariant complex [sorbitol positive and sorbitol negative]) was isolated from a surgically placed central venous catheter tip and three cultures of blood from a 2-year-old child diagnosed with metastatic hepatoblastoma. The organism's unique phenotypic profile and ribotype patterns differed from those of the type and reference strains of the M. fortuitum complex and indicate that this organism may represent a new pathogenic taxon. ( info) |
| ochrobactrum anthropi (O. anthropi ), formerly known as achromobacter CDC group Vd, is a gram-negative bacillus that is aerobic, oxidase producing, and nonlactose fermenting. This organism has been found in environmental and hospital water sources and has pathogenic potential in humans. Most reports in the literature of O. anthropi bacteremia are associated with intravenous line infections. We describe a case of bacteremia with O. anthropi in a 33-month-old boy with acute osteomyelitis. O. anthropi bacteremia also has been reported in immunocompromised hosts. Rarely, O. anthropi has been a cause of soft tissue or bone infection. ( info) |
6/1318. Staphylococcus aureus with reduced susceptibility to vancomycin isolated from a patient with fatal bacteremia. A Staphylococcus aureus isolate with reduced susceptibility to vancomycin was obtained from a dialysis patient with a fatal case of bacteremia. Comparison of the isolate with two methicillin-resistant S. aureus (MRSA) isolated obtained from the same patient 4 months earlier suggests that the S. aureus with reduced susceptibility to vancomycin emerged from the MRSA strain with which the patient was infected. Atypical phenotypic characteristics, including weak or negative latex-agglutination test results, weak or negative-slide coagulase test results, heterogeneous morphologic features, slow rate of growth, and vancomycin susceptibility (by disk diffusion test) were observed. ( info) |
| mycoplasma penetrans, a rare bacterium so far only found in hiv-infected persons, was isolated in the blood and throat of a non-hiv-infected patient with primary antiphospholipid syndrome (whose etiology and pathogenesis are unknown). ( info) |
| Systemic infection caused by arcanobacterium haemolyticum is uncommon. We report a case of empyema and bacteraemia caused by this organism concomitant with mycoplasma pneumoniae infection. ( info) |
9/1318. The emergence of decreased susceptibility to vancomycin in staphylococcus epidermidis. BACKGROUND: coagulase-negative staphylococci (CNS) are the major cause of nosocomial bloodstream infection. Emergence of vancomycin resistance among CNS is a serious public health concern, because CNS usually are multidrug-resistant, and glycopeptide antibiotics, among which only vancomycin is available in the United States, are the only remaining effective therapy. In this report, we describe the first bloodstream infection in the united states associated with a staphylococcus epidermidis strain with decreased susceptibility to vancomycin. methods: We reviewed the hospital's microbiology records for all CNS strains, reviewed the patient's medical and laboratory records, and obtained all available CNS isolates with decreased susceptibility to vancomycin. blood cultures were processed and CNS isolates identified by using standard methods; antimicrobial susceptibility was determined by using minimum inhibitory concentration (MIC) and disk-diffusion methods. Nares cultures were obtained from exposed healthcare workers (HCWs) to identify possible colonization by CNS with decreased susceptibility to vancomycin. RESULTS: The bloodstream infection by an S. epidermidis strain with decreased susceptibility to vancomycin occurred in a 49-year-old woman with carcinoma. She had two blood cultures positive for CNS; both isolates were S. epidermidis. Although susceptible to vancomycin by the disk-diffusion method (16-17 mm), the isolates were intermediate by MIC (8-6 microg/mL). The patient had received an extended course of vancomycin therapy; she died of her underlying disease. No HCW was colonized by CNS with decreased susceptibility to vancomycin. CONCLUSIONS: This is the first report in the united states of bloodstream infection due to S. epidermidis with decreased susceptibility to vancomycin. Contact precautions likely played a role in preventing nosocomial transmission of this strain, and disk-diffusion methods may be inadequate to detect CNS with decreased susceptibility to vancomycin. ( info) |
10/1318. Rapid and definitive diagnosis of infectious diseases using peripheral blood smears. A timely diagnosis is essential in the management of septicemia and septic shock. Three patients are described, all of whom presented with fever and one of whom was hypotensive at the time of admission. In each patient, rapid diagnosis of the cause of fever was possible because microorganisms were identified on a peripheral blood smear obtained at the time of admission. This identification permitted prompt initiation of appropriate antimicrobial therapy. In addition, a literature review of use of peripheral blood smears in the diagnosis of bacterial, fungal, and parasitic infections is provided. ( info) |