Streptococcal necrotizing fasciitis ("flesh-eating strep infection").

Streptococcal necrotizing fasciitis, popularized in the lay literature as the "flesh-eating infection" has gained great notoriety. Necrotizing fasciitis may be lethal not only due to its severity, but also because of difficulty in diagnosis during its early stages. Absence of immunity against certain streptococcal proteins increases the severity of infection. Necrotizing fasciitis may be distinguished from other streptococcal skin and soft tissue infections by clinical examination, imaging studies, and biopsy. Treatment requires a combined medical-surgical approach.

Spontaneous regression of lymphosarcoma in a dog.

Lymphosarcoma in a dog regressed without chemotherapy or radiotherapy. The drugs administered to the dog before the regression were not sufficient to influence the neoplastic disease. During the next 12 months, the dog was evaluated periodically for signs of recurrence of the lymphosarcoma. The disease remained in clinical regression during this period. Spontaneous regression of lymphosarcoma in dogs is extraordinarily unusual. A variety of factors may affect remission in, and survival times of dogs with lymphosarcoma.

Treatment of septicemic patients with cefoxitin: pharmacokinetics in renal insufficiency.

Experience with cefoxitin in the treatment of septicemia of diverse etiologies in 11 patients is reviewed. Results of a small study of the pharmacokinetics of cefoxitin in patients with renal insufficiency, which was used as a guideline for determining the dosage of cefoxitin for severely ill patients with renal insufficiency, are included. In addition, a summary of data on file at Merck Sharp and Dohme Research Laboratories (Rahway, New Jersey) that concern 135 bacteremic patients who were treated with cefoxitin and evaluated is presented. Although information derived from septicemic patients is among the most difficult to interpret in regard to the efficacy of an investigational antibiotic, both our experience and the summary of data confirm that cefoxitin is a potent antibiotic suitable for use in septicemic patients when the etiologic agent is susceptible; the data also demonstrate that cefoxitin has a significantly expanded spectrum of activity as compared with that of cephalothin.

A controlled investigation of the pharmacokinetics of gentamicin and tobramycin in obese subjects.

For determination of the best basis on which to calculate dosages of gentamicin or tobramycin to be administered to obese patients, the pharmacokinetics of these drugs were studied in 13 obese subjects and 13 subjects of a normal weight following intravenous infusion of 1 mg/kg. Half-lives, elimination constants, and absolute and relative volumes of distribution were calculated. Concentrations of drug in serum were significantly higher and relative volumes of distribution were significantly lower in obese subjects as compared with controls. However, relative volumes of distribution based on lean body mass of obese subjects were significantly greater than those of normal-weight subjects. These results indicate that gentamicin and tobramycin are distributed less to adipose tissue than to other tissues, but partial distribution to adipose tissue does occur. The mean relative volume of distribution in obese subjects closely approximated that in normal subjects when normalized body mass plus 40% of the adipose mass was used as the total weight in obese subjects.

Sources of gram-negative bacilli colonizing the tracheae of intubated patients.

Twenty acutely ill patients requiring prolonged orotracheal intubation were studied to determine the source and progression of gram-negative bacilli colonizing the trachea. Organisms recovered from daily tracheal, hypopharyngeal, and rectal cultures were typed and speciated to identify identical strains at the three sites. All patients acquired gram-negative bacilli in the trachea by day 3 after intubation. Thirty organisms that were not recovered from the tracheal aspirate immediately following intubation were isolated for at least two days some time thereafter. Nine of the 30 colonizing bacteria were Enterobacteriaceae, and all were found in another culture site, usually the hypopharynx, before isolation from the trachea. In contrast, only four of the 21 non-Enterobacteriaceae that colonized the trachea were recovered previously from either the hypopharynx or rectum, a finding which represents a significant difference (P = 0.0002). Quantitation of isolates from the hypopharynx was of no value in predicting subsequent acquisition in the trachea, and the numbers of bacteria recovered from the first positive tracheal specimen were not predictive of subsequent persistence in the trachea.

Antifungal properties of polymyxin B and its potentiation of tetracycline as an antifungal agent.

High concentrations of polymyxin B inhibited the growth of Candida albicans and Saccharomyces cerevisiae. When these yeasts were incubated with concentrations of polymyxin B too low to affect growth, and were then exposed to tetracycline, protein synthesis was inhibited and at least 99% of the organisms were killed. Neither inhibition of protein synthesis nor cell death occurred in cultures treated with high concentrations of tetracycline alone. We conclude that polymyxin B at high concentrations affects the cell membrane of yeasts, which results in inhibition of growth. At low concentrations, it increases the permeability of the yeast cell membrane to tetracycline, which then inhibits protein synthesis and leads to cell death.