Blood samples, which were obtained from patients who lived in a rural area with approximately 500 acute-care hospital beds, were cultured from 1990 through 1997. We retrospectively reviewed the blood cultures that yielded Clostridium species (74 [0.12%] of 63,296 cultures). These were obtained from 46 different hospitalized patients (incidents per hospital, 0.03%). The source of the Clostridium species was a gastrointestinal site in 24 patients (52.2%). The most frequently identified Clostridium species was Clostridium perfringens (in 10 [21.7%] of patients), followed by Clostridium septicum (in 9 [19.6%]). Thirty-one patients (67.4%) were aged > or =65 years, 13 patients (28.3%) had diabetes mellitus, and underlying malignancy was present in 22 patients (47.8%). The mortality rate of patients whose condition had been managed surgically was 33%; for those patients whose conditions required medical management, the mortality rate was 58%. Clostridium bacteremia in these patients usually had a gastrointestinal source, it often occurred in patients with serious underlying medical conditions, and it rarely was the result of traumatic farm accidents.

The prevalence of Aeromonas hydrophila in stool specimens from patients with diarrhea was studied during 18 months. A. hydrophila was found in 1.1% of patients with diarrhea and in none of 533 control patients (P < 0.02). Cases were detected 1.5 times more often during the summer months than the winter months, and most occurred in children less than 2 years of age. Clinical features included fever greater than 38°C (55%), abdominal cramps (35%), vomiting (25%), and duration of illness greater than 10 days (50%). Detection of A. hydrophila in stools was facilitated by the use of sheep blood agar with 15 ,ug of ampicillin per ml which was flooded with oxidase reagent after growth. A cytotoxin was produced by 62% of the isolates, and the cytotoxic strains showed positive results in a hemolysin assay and a lysine decarboxylase reaction.

In patients with acute disseminated Lyme disease but without meningitis, oral doxycycline and parenterally administered ceftriaxone were equally effective in preventing the late manifestations of disease.

No abstract

Patients treated for 10 days with antibiotic therapy for early Lyme disease have long-term outcomes similar to those of patients treated with longer courses. Treatment failure after appropriately targeted short-course therapy, if it occurs, is exceedingly rare.