Combination antimicrobial agent therapy has been advocated for treatment of gram-negative bacteremia, including that caused by KlebsielUa spp. We performed a prospective, observational, 10-hospital collaborative study to evaluate the efficacy of antibiotic combination therapy versus that of monotherapy for 230 consecutive patients with KiebsieUla bacteremia. The species involved were K. pneumoniae (82%), K. oxytoca (15%), and K. ozaenae (0.4%). Of the bacteremias, 26% were polymicrobial in nature. A total of 53% of cases were nosocomial infections. The most common portals were the urinary tract (28%), biliary tract (12%), lung (10%b), and abdomen (9%k). Some 49 and 51% of the patients had received monotherapy and antibiotic combination therapy (beta-lactam plus aminoglycoside), respectively; 14-day mortalities in the two groups were 20 and 18%, respectively. However, for the subgroup of patients who experienced hypotension within 72 h prior to or on the day of the positive blood culture, those patients who received combination therapy experienced significantly lower mortality (24%) than did those who received monotherapy (50%k). We conclude that monotherapy with an antibiotic that is active in vitro against KiebsieUla (beta-lactam or aminoglycoside) is sufficient therapy for less severely ill patients (immunocompetent, urinary tract portal, mentally alert, normal vital signs). On the other hand, for severel ill patients who experience hypotension, antibiotic combination therapy with a beta-lactam and an aminoglycoside agent is preferred.Klebsiella spp. are the second most frequent cause of gram-negative bacteremia (3,5,12,14). Combination therapy with a beta-lactam and an aminoglycoside has been advocated for treatment of Klebsiella bacteremia because of its notable mortality (1,11,15).Most studies of bacteremia have focused on Klebsiella spp. not as a single entity but, rather, have included it in the category of gram-negative bacteremias. This is problematic, given the inherent differences in antibiotic susceptibility and virulence among the aerobic gram-negative rods. Young (15) has also pointed out that failure to stratify patients by underlying disease category in most studies of therapy for gram-negative bacteremia has resulted in invalid comparisons of antibiotic efficacy.We performed a prospective, observational, multicenter collaborative study to evaluate the efficacy of antibiotic combination therapy versus monotherapy on the outcome of Klebsiella infections. We made a concerted effort to address those areas of weakness that have characterized previous studies, including a prospective rather than retrospective study design, adequate sample size for statistical evaluation, assessment for severity of illness, and requirement for bacteremia as an eligibility criterion. Furthermore, given the large sample size of 230 patients, analysis by subgroups including underlying disease was feasible. MATERIALS AND METHODSStudy design. From 1986 to 1987, 230 consecutive patients from whose blood Klebsiella spp. were ...

Streptococcus agalactiae (S. agalactiae), also referred as group B streptococcus (GBS), is an important pathogen in neonates and a rare cause of invasive infection in adults. It is well known that GBS endocarditis is a virulent infection that can cause serious complications. The overall mortality rate remains high despite surgical treatment. We describe a case of native mitral valve endocarditis caused by GBS in an 86-year-old woman treated medically.

Mycobacterium porcinum has been reported to cause a variety of illnesses including wound infections, respiratory tract infections, osteomyelitis and catheter-related bacteremias. We report the first case of M. porcinum peritonitis in a patient on continuous ambulatory peritoneal dialysis (CAPD). A 67-year-old woman on CAPD presented with three weeks of constitutional symptoms and abdominal pain. Peritoneal fluid cultures on day three grew acid-fast rods. Nocardiosis was suspected and the patient was empirically treated with amikacin and trimethoprim-sulfamethoxazole. The dialysis catheter was removed. Two weeks later final culture results revealed M. porcinum. Ciprofloxacin and trimethoprim-sulfamethoxazole were initiated with good clinical response.