Molecular typing of multiresistant Klebsiella pneumoniae isolated from children from northern Jordan.

Twenty-nine clinical isolates of community acquired Klebsiella pneumoniae obtained from 17 children with malnutrition were characterized by antibiotic susceptibility, plasmid analysis, and random amplified polymorphic DNA (RAPD) techniques. Disc diffusion methodology was used to test the susceptibility of the isolates to 13 antibiotics: amoxycillin, cephapirin, ceftazidime, cefoxitin, cefotaxime, aztreonam, gentamicin, ciprofloxacin, chloramphenicol, erythromycin, nalidixic acid, trimethoprim and amoxycillin-clavulanic acid. All the isolates showed multiresistance patterns (15 patterns) ranging from resistance to two antibiotics to resistance to 10 antibiotics. All isolates were resistant to amoxycillin and erythromycin. Ten K. pneumoniae isolates producing extended-spectrum beta-lactamases (ESBLs) as evidenced by the double-disc diffusion synergy test were isolated sporadically from six patients. Six of these 10 isolates were hyperproducers of ESBL, which resulted in increased resistance to the beta-lactam-beta-lactamase inhibitor combination amoxycillin-clavulanic acid. Plasmid analysis showed plasmid ranging in size from 48 kilobases (kb) to 1.4 kb. All the 29 isolates shared the same plasmid 26 kb. There was a consistent relationship between antibiotype and plasmid profiles for each pair of isolates obtained from five individual patients. RAPD analysis using a single (10-mer) primer demonstrated that the isolates that have the same antibiotype and the same plasmid profile had different RAPD fingerprint patterns. These results demonstrate that the RAPD technique is better than antibiotype characterization and a plasmid analysis profile for typing K. pneumoniae as well as for revealing strain differences.

Bacterial translocation and gram-negative bacteremia in patients with hematological malignancies.

Between 1976 and 1982, Enterobacteriaceae and Pseudomonas aeruginosa were prospectively counted in fecal specimens from leukemic patients with gram-negative bacteremia. The strains isolated from the blood and feces of 55 patients were compared. Translocation of the dominant fecal strain of Enterobacteriaceae or P. aeruginosa was observed in 45 cases (82%) and was strongly associated with granulocytopenia of less than 10(2) cells/microliter (P less than .0001). Thirteen (81%) of 16 patients with bacteremia caused by P. aeruginosa were intestinal carriers of the same strain, whereas only 2 (5%) of 39 patients with bacteremia caused by Enterobacteriaceae were carriers of P. aeruginosa. Bacterial translocation of Enterobacteriaceae was not associated with an abnormally high fecal population of the translocating strain. Prospective quantitative and qualitative analyses of fecal flora were useful in forecasting the most probable translocating gram-negative organism in neutropenic leukemic patients with clinical signs of bacteremia.

Epidemiology of enterobacteria resistant to cefotaxime in hospital.

Cefotaxime treatment eliminates normally susceptible strains of enterobacteria from the digestive tract, and increases intestinal carriage of resistant enterobacteria in individuals. However the global rate of such carriage remains low in hospitalized patients and resistant strains are exceptionally isolated from bacteraemia in spite of an intensive use of this antibiotic. The epidemiology of resistant strains of enterobacteria has to be carefully monitored. The results obtained by the control of faecal carriage shows that this technique is a means of surveying evolution in this area.