Macrorestriction analysis of Pseudomonas aeruginosa in colonized burn patients.

The colonization of hospitalized patients by Pseudomonas aeruginosa at an intensive care unit for burn victims was studied over a one-year period. A total of 231 isolates from 12 patients were analyzed by macrorestriction analysis. The results revealed that most patients were infected with only one to three different strains. In several patients Pseudomonas aeruginosa isolates of the same clonal lineage exhibited considerable differences in their macrorestriction fragment pattern. Digestion with further restriction enzymes, however, allowed differentiation between clonal variants due to a high genetic drift and superinfection with a different Pseudomonas aeruginosa strain. Isolates of the same clonal lineage could be isolated from several patients as well as from the patients' environment. Notably, Pseudomonas aeruginosa could be isolated from sedimentation plates. Thus, patients may have been extensively cross-infected on the ward. These data underline the importance of strict infection control measures and of regular surveillance for Pseudomonas aeruginosa by an appropriate typing method, i.e. one that can differentiate strains with high genomic variability.

Risk of bacteremia induced by transesophageal echocardiography: analysis of 100 consecutive procedures.

The incidence of bacteremia induced by transesophageal echocardiography (TEE) and, consequently, the need for an antibiotic prophylaxis before TEE is still controversial. Therefore, we studied the incidence of bacteremia associated with TEE prospectively in 100 consecutive patients without clinical or laboratory signs of bacterial infection. Blood samples were drawn immediately before and at 0, 5, and 15 minutes after TEE. In addition, swabs were taken from the pharyngeal region before TEE and from the distal part of the TEE-probe before and after TEE. All blood cultures taken before TEE remained sterile. After TEE, three positive blood cultures were found in two patients: the first patient had two different species of coagulase-negative staphylococci in cultures taken at 0 minutes (Staphylococcus capitis) and 15 minutes (Staphylococcus cohnii) after TEE, whereas the sample taken after 5 minutes remained sterile. In the second patient, Propionibacterium species appeared after 7 days of processing in a culture taken immediately after TEE, but not in the samples taken after 5 and 15 minutes. None of the three microorganisms found in the blood were simultaneously isolated in pharyngeal specimens or TEE-probe specimens of the same patient. Thus positive blood cultures in both patients were considered contaminated. This study demonstrates that TEE, when performed by an experienced investigator, is not associated with an increased risk of bacteremia. Accordingly, it is justified to perform TEE examinations (also in high-risk patients) without antibiotic prophylaxis.

[Infection management in surgical intensive care patients]. / Infektiologisches Management bei chirurgischen Intensivpatienten.

Achieving significant reductions in the rate of infections contracted in hospital requires an integrated approach. Such an approach is comprised of standardized procedures in the areas of prevention, diagnosis, therapy, and tracking. Prevention must begin by differentiating between exogeneous and primary or secondary endogenous infections. For infections already contracted, diagnosis and therapy must be standardized to the greatest possible extent, thereby discouraging recourse to a polypragmatic approach. Finally, tracking provides important information about the type, number, and origin of infections, as well as about the resistance of pathogens and the success of infection-control techniques. Standardization should not be limited to a single ward or hospital, but should extend to the national and even international level.

Antibacterial activity of sucralfate in human gastric juice.

A series of experiments was conducted to determine the rate of bacterial growth in human gastric juice at various pH values in relation to the addition of sucralfate and antacid. Whereas the addition of antacid resulted in bacterial growth in gastric juice, sucralfate showed an antibacterial effect. This may account for the decreased rate of pneumonia among intensive-care patients who are receiving artificial ventilation and being treated with sucralfate for the prevention of stress-induced gastrointestinal bleeding compared with the rate in patients receiving conventional prophylaxis with histamine (H2)-antagonists or antacids.