Primary cutaneous mucormycosis in trauma patients.

Primary cutaneous mucormycosis in trauma patients has been rarely reported. We describe three cases occurring in noncompromised hosts and review the literature. Prompt diagnosis and aggressive treatment with vigorous local care and appropriate antibiotics are recommended.

Progressive disseminated histoplasmosis in patients with the acquired immune deficiency syndrome: a report of 12 cases and a literature review.

Progressive disseminated histoplasmosis is an increasingly common cause of infection in patients with acquired immune deficiency syndrome (AIDS) from areas endemic for histoplasmosis. We report 12 cases of progressive disseminated histoplasmosis associated with AIDS and review 20 previously reported cases. The clinical presentation of progressive disseminated histoplasmosis is nonspecific with persistent fever, weight loss, and splenomegaly. Frequently progressive disseminated histoplasmosis was the initial clue to the presence of AIDS. Bone marrow culture is the best method for establishing a diagnosis. Relapses were common both with ketoconazole and after a 2.0 to 2.5 g course of amphotericin B. This suggests a 2.0 to 2.5 g course of amphotericin B followed by long term ketoconazole suppression may be the best therapeutic regimen in these patients.

Lack of correlation between known virulence properties of Aeromonas hydrophila and enteropathogenicity for humans.

Five strains of Aeromonas hydrophila were selected for use in volunteer challenge trials. All five strains produced cytotoxin, hemolysin enterotoxin, lysine decarboxylase, acetylmethylcarbinol, and DNase. Two strains hydrolyzed esculin. All strains produced purulent hemorrhagic fluid accumulation in rabbit ileal loops, but failed to induce keratoconjunctivitis in guinea pigs. None of the strains produced mannose-resistant hemagglutinins. In challenge studies, diarrhea was demonstrated in only 2 of 57 human volunteers with doses ranging from 10(4) to 10(10) CFU. One person experienced mild diarrhea with 10(9) CFU of strain 6Y. A second person developed moderate diarrhea with 10(7) CFU of strain 3647. At higher doses, no diarrhea was seen in any of the volunteers. The other three strains (B158, SSU, 3284) failed to cause diarrhea and were not recovered from stools of volunteers. Additional virulence properties of A. hydrophila need to be sought before enteropathogenicity for humans can be established.

Inactivation of Norwalk virus in drinking water by chlorine.

Norwalk virus in water was found to be more resistant to chlorine inactivation than poliovirus type 1 (LSc2Ab), human rotavirus (Wa), simian rotavirus (SA11), or f2 bacteriophage. A 3.75 mg/liter dose of chlorine was found to be effective against other viruses but failed to inactivate Norwalk virus. The Norwalk virus inoculum remained infectious for five of eight volunteers, despite the initial presence of free residual chlorine. Infectivity in volunteers was demonstrated by seroconversion to Norwalk virus. Fourteen of 16 subjects receiving untreated inoculum seroconverted to Norwalk virus. Illness was produced in four of the eight volunteers and in 11 of 16 control subjects. A similar Norwalk virus inoculum treated with a 10 mg/liter dose of chlorine produced illness in only one and failed to induce seroconversion in any of eight volunteers. Free chlorine (5 to 6 mg/liter) was measured in the reaction vessel after a 30-minute contact period. Norwalk virus appears to be very resistant to chlorine which may explain its importance in outbreaks of waterborne disease.

Use of trimethoprim-sulfamethoxazole for treatment of infections due to Nocardia.

Trimethoprim-sulfamethoxazole (TMP-SMZ) was used for treatment of 34 patients with pulmonary or cutaneous nocardiosis. Of nine patients with primary cutaneous disease, eight had rapid resolution of their infection after short-term therapy and none have relapsed after a follow-up of more than six months. The 25 patients with pulmonary nocardiosis had a good clinical response, but three of five (60%) who completed less than three months of therapy relapsed within four weeks. Of the 10 patients who completed four to six months of therapy, only one (10%) relapsed and this relapse was due to drug resistance. By the method of serial dilution in agar, 96% of 59 isolates of Nocardia had MICs of SMZ of less than 25 micrograms/ml. Fewer than 20% were susceptible to 2.5 micrograms of TMP/ml. Synergy between TMP and SMZ was usually present with ratios of TMP to SMZ of 1:5, 1:1, or 5:1, but was less common at a ratio of 1:20. Disk susceptibility testing was easy to perform and readily separated sensitive from resistant strains. TMP-SMZ is highly effective for the treatment of nocardiosis, but the question of whether it is more effective clinically than a sulfonamide alone remains unanswered.

Use of the pneumococcal vaccine.

High-risk patients who should receive the pneumococcal vaccine include asplenic patients, those with sickle cell anemia, nephrotic syndrome, congestive heart failure, pulmonary or renal disease, insulin-dependent diabetics, alcoholics with cirrhosis and immunocompromised patients. The vaccine should not be used in children under two years of age. It is safe, relatively inexpensive and effective when antibody response can be generated.

Cutaneous lesions due to Mycobacterium kansasii.

A recipient of a renal homograft had cutaneous lesions on the lower extremities that resembled pyogenic abscesses. Staphylococcus aureus consistently grew from cultures and despite appropriate antibiotics, the lesions did not completely resolve. When special cultures were done, Mycobacterium kansasii was discovered. In immunocompromised patients with infectious cutaneous lesions, skin biopsy using appropriate stains and cultures should be considered early in the course of the illness.

Primary cutaneous nocardiosis.

Seven patients with primary cutaneous nocardiosis were seen during a 20-month period. Six patients had a history of local trauma to an extremity or did frequent yard work. The spectrum of clinical disease included cellulitis, pustules,pyoderma, or lymphocutaneous syndrome mimicking sporotrichosis. Evidence of Nocardia infection elsewhere was absent, and no patient had a serious underlying disease. Nocardia brasiliensis was isolated from four cases, and N asteroides was identified in the other three patients. In two patients, disease resolved without chemotherapy, while a short course of a sulfonamide with or without trimethoprim therapy was successful in the remaining cases. The relatively benign nature of this disease, the usual failure to obtain cultures of superficial skin infections, and our accumulation of seven cases in less than two years suggest this disease is more common than previously recognized.

Rat bite fever misdiagnosed as Rocky Mountain spotted fever.

A patient who had been exposed to ticks and who had also been bitten by a laboratory rat developed fever, headache, and a rash. He was treated with chloramphenicol for Rocky Mountain spotted fever, and recovered. Blood cultures, however, grew Streptobacillus moniliformis, a causative agent of rat bite fever. The case report illustrates the clinical similarities between rat bite fever and Rocky Mountain spotted fever.

Role of Escherichia coli colonisation factor antigen in acute diarrhoea.

The role of colonisation factor antigen (C.F.A.) in diarrhoea was studied in volunteers who ingested either E. coli H-10407, which possessed C.F.A., or H-10407-P, which lacked C.F.A. In the first study the dose given was 10(6) C.F.A.+ or C.F.A.- E. coli; in the second study the dose was 10(8) of the same organisms. Diarrhoea, with or without other symptoms, occurred only in those who ingested 10(8) C.F.A.+ E. coli. Those volunteers taking the C.F.A.- strain shed the test organism in the stool for only 2 or 3 days whereas those ingesting the C.F.A+ strain shed the organism until the end of the study (7 days). Antibody responses in those ingesting the C.F.A.+ strain were: anti-C.F.A., 7 of 12 volunteers; antitoxin, 6 of 13; and anti-O78 somatic antigen, 11 of 13. No volunteer ingesting the C.F.A. organism seroconverted to any of the antigens. The study showed the importance of C.F.A. in the pathogenesis of human disease due to toxigenic E. coli.

Differences in serological responses and excretion patterns of volunteers challenged with enterotoxigenic Escherichia coli with and without the colonization factor antigen.

Double-blind studies were performed to compare the virulence of enterotoxigenic Escherichia coli with and without the fimbriate colonization factor antigen (CFA), using young healthy adults (mean age, 23 years) as volunteers. In the first study one group of volunteers ingested 1 X 10(6) E. coli H-10407, the CFA-positive strain, and another group ingested 1 X 10(6) E. coli H-10407-P, the CFA-negative spontaneous derivative of strain H-10407. The second study was similar except that the test strains were administered at a dose of 1 X 10(8) viable cells. Three parameters of infection were monitored: (i) diarrhea and associated symptoms; (ii) excretion pattern of test strains; and (iii) humoral antibody response to CFA, somatic antigen, and heat-labile enterotoxin. Significant signs of illness occurred only in six of seven volunteers who ingested E. coli H-10407 at a dose of 1 X 10(8). At both doses, E. coli H-10407-P appeared in the stool on day 1 postchallenge and disappeared by day 4. In contrast, strain H-10407 was persistently excreted from the first to the last day of the study. Also, only those volunteers in the H-10407 challenge groups (12 of 13 analyzed) responded with a fourfold antibody titer rise to CFA, somatic antigen, and/or heat-labile enterotoxin. No reversion of H-10407-P to H-10407 was detected.

Evaluation of spectinomycin and gentamicin in the treatment of hospitalized patients with resistant urinary tract infections.

Spectinomycin hydrochloride 140 mg/kg/day and gentamicin 3 mg/kg/day were evaluated in the treatment of 50 hospitalized patients with urinary tract infections. Seven patients (28%) in the spectinomycin group had positive urine cultures after 72 hours of therapy due to initial resistance of the organism (5 isolates) or development of resistance to spectinomycin (2 isolates). Response to gentamicin therapy was uniformly satisfactory. Complications of spectinomycin therapy included pain and induration at the injection site (11 patients) and elevated serum creatinine values (2 patients). Ototoxicity was noted in three patients given gentamicin. Peak serum concentrations of spectinomycin (range 55-157 microgram/ml) and gentamicin (range 2.8--8.5 microgram/ml) showed marked interpatient variation. Spectinomycin appears to be of limited value in the treatment of urinary tract infections caused by gram-negative bacilli.

Minocycline treatment failure in pneumonia caused by minocycline-sensitive Streptococcus pneumoniae.

A previously healthy 23-year-old white woman had fulminant pneumococcal pneumonia complicated by empyema and bilateral pneumothoraces. Despite early treatment with the recommended doses of minocycline, the disease progressed. The S pneumoniae isolate was resistant to a 30microgram tetracycline disk and showed an MIC of 3.13microgram/ml for minocycline and 12.5 microgram/ml for tetracycline; these levels are considered by the manufacturer to indicate sensitivity to minocycline and intermediate sensitivity to tetracycline. The tetracyclines, including minocycline, should not be used to treat bacterial pneumonia since resistant strains of pneumococci are not uncommon and inffective treatment can lead to rapid progression of the infection. This case suggests that the levels of minocycline considered to indicate sensitivity in vitro be reassessed.