Jeffrey D. Band

Laboratory-Acquired Infection with Pseudomonas pseudomallei (Melioidosis)

INFECTION with Pseudomonas pseudomallei acquired in the Western hemisphere is exceedingly rare. Careful questioning of patients with acute or chronic melioidosis will usually reveal a recent or rem...

EPIDEMIC OF MENINGOCOCCAL MENINGITIS IN BAMAKO, MALI: EPIDEMIOLOGICAL FEATURES AND ANALYSIS OF VACCINE EFFICACY

Many studies have demonstrated the efficacy of meningococcal vaccine in nonepidemic meningococcal meningitis, but few have examined its efficacy in epidemic conditions. The effects of the vaccine on the course of a meningococcal meningitis epidemic in Bamako, Mali, between January and April, 1981, were studied. The vaccine was effective in limiting further spread of the epidemic. The attack rate among those who received vaccine was lower than that in the unvaccinated (0.7/10 000 vs 4.7/10 000), and the case-fatality rate among vaccinees in whom meningitis developed was lower than that of the unvaccinated. Routine vaccination against meningococcal meningitis in Africa may be impracticable owing to the cost, the relatively short duration of effectiveness, and the irregular occurrence of epidemics. Vaccination early in the course of an epidemic, however, appears to be a useful and practicable method of limiting the spread of disease.

Pseudomonas aeruginosa serotype 0:9: New cause of whirlpool-associated dermatitis

In a five-day period, dermatitis developed in nearly one fourth of the guests staying at a large Georgia hotel. Dermatitis was associated with use of the hotels whirlpool (p less than 0.001) and indoor swimming pool (p less than 0.001). Attack rates were highest among persons more frequently exposed to the whirlpool, in persons under 10 years of age, and during periods of heaviest bather load. Pseudomonas aeruginosa was isolated from skin lesions of 13 of 20 patients from whom culture specimens were taken. Ten isolates were serotype 0:9. The whirlpools water grew P. aeruginosa serotype 0:9; however, the whirlpools automatic chlorinator was functioning properly, the pH of the water was 7.2, and the free chlorine level was 0.6 mg/liter. This is the first report of a whirlpool-associated outbreak caused by P. aeruginosa serotype 0:9. Our findings suggest that this strain may not be readily sensitive to recommended chlorine concentrations.

An outbreak of Pseudomonas aeruginosa respiratory tract infections associated with intrinsically contaminated ultrasound transmission gel.

We describe an outbreak of Pseudomonas aeruginosa respiratory tract infections related to intrinsically contaminated ultrasound gel used for intraoperative transesophageal echocardiograms in cardiovascular surgery patients. This investigation led to a product safety alert by the Food and Drug Administration and the development of guidelines for appropriate use of ultrasound gel.

Emergence of Vancomycin Resistance inStaphylococcus aureus

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.

A Creeping Suspicion

A 51-year-old woman was brought to the emergency room after the development of nonsensical speech, including confused word choices and difficulty with naming objects and counting. Her husband noted that she had reported headache, nausea, vomiting, and fatigue the previous day.