Pseudallescheria boydii brain abscess: association with near-drowning and efficacy of high-dose, prolonged miconazole therapy in patients with multiple abscesses.

Brain abscess caused by Pseudallescheria boydii is a highly lethal infection, usually seen in immunosuppressed patients. Five patients with P. boydii brain abscesses are described. Four of these patients acquired their infection after near-drowning; 1 patient developed an abscess after penetrating head trauma. Two patients survived their infections, which included involvement of other body sites (lung, eye, bone) as well as multiple undrained brain abscesses, after prolonged courses of high-dose parenteral miconazole (80-90 mg/kg/d). Progressive increases in miconazole dosage during the treatment periods were required to produce serum levels above the minimum inhibitory concentrations of the fungal isolates.

Co-infection with Legionella pneumophila and Pneumocystis carinii in a patient with chronic lymphocytic leukemia.

A patient with chronic lymphocytic leukemia was found to have pneumonitis caused by a simultaneous Pneumocystis carinii and Legionella pneumophila infection. Although both microorganisms frequently cause pulmonary infections in immunocompromised patients, co-infection has not been reported. This patient responded to antimicrobial therapy, but superinfection with Candida albicans led to his death. As there are numerous infective and noninfective causes of pneumonia in such patients, this case illustrates that the identification of a single etiologic agent does not obviate the search for other potential causes.

Evaluation of single-dose ciprofloxacin in the eradication of Neisseria meningitidis from nasopharyngeal carriers.

The ability of a single oral 750-mg dose of ciprofloxacin to eradicate Neisseria meningitidis from persistent nasopharyngeal carriers was prospectively evaluated in a placebo-controlled, randomized, double-blinded study. Cultures of specimens taken from all 23 ciprofloxacin-dosed subjects 1 day postdose were negative; cultures from 96% of these subjects were negative at 7 and 21 days postdose, including a specimen from a subject colonized with a minocycline-resistant strain. Of 22 placebo recipients, 20 (91%) remained culture positive. Single-dose ciprofloxacin appears efficacious for meningococcal prophylaxis.

New causes of pneumonia, meningitis, and disseminated infections associated with immersion.

Immersion in water increases the risk of infection by certain microorganisms, including bacteria, fungi, and parasites. Physicians should be aware of this relationship because many of these infections are not normally encountered except in association with water exposure. The morbidity and mortality associated with these infections may be substantial. Clinical features of pneumonia, disseminated infection, and central nervous system infections are detailed.

Emergence of resistance in gram-negative bacteria during therapy with expanded-spectrum cephalosporins.

To assess the clinical importance of emergence of beta-lactam resistance caused by stable derepression of chromosomal beta-lactamases, sequential cultures from patients treated with expanded-spectrum cephalosporins were monitored for the persistence of bacteria possessing these enzymes. Antibiotic susceptibilities and beta-lactamase production before and after cefoxitin induction were determined in sequential isolates of individual bacterial strains. Of 49 strains isolated from 44 patients, 25 strains (51%) were eradicated by cephalosporin therapy, 17 strains (35%) persisted with unchanged susceptibility in sequential cultures, and 7 strains (14%) from 7 patients developed multiple beta-lactam resistance during cephalosporin therapy. In 6 of the 7 strains, resistance was associated with stable derepression of beta-lactamases. In the patient group whose strains developed resistance, subsequent use of non-beta-lactam antibiotics was more frequent and mortality was higher.

Emergence of resistance in gram-negative bacteria: a risk of broad-spectrum beta-lactam use.

A number of new beta-lactam antibiotics have been developed to overcome bacterial resistance to older agents. Such resistance usually is caused by plasmid-mediated, constituently produced beta-lactamases. Second- and third-generation cephalosporins, ureidopenicillins, acylamino penicillins, and monobactams generally are resistant to hydrolysis by these enzymes. However, inducible beta-lactamases may confer resistance to these antibiotics. This induction may occur spontaneously or in response to cefoxitin or other beta-lactam agents. The mechanisms by which inducible enzymes produce this resistance are reviewed and implications for the prophylactic and therapeutic use of newer beta-lactams are considered.

Encephalitis associated with Rocky Mountain spotted fever.

We present a fatal case of Rocky Mountain spotted fever. Despite the presence of clinical and laboratory evidence suggesting widespread vasculitis, pathologic lesions were found only in the central nervous system.

Actinomycosis of the prostate.

We report a case of actinomycosis of the prostate with symptoms of acute prostatitis. Laparotomy was required to establish an etiological diagnosis. Long-term therapy with erythromycin resulted in a clinical cure.

Evaluation of Sch 29,482 in the eradication of Neisseria meningitidis from nasopharyngeal carriers.

Fifty-eight chronic carriers of Neisseria meningitidis were given 250 mg of Sch 29,482 or placebo orally every 6 h for 4 days. Although 22 of 29 subjects taking Sch 29,482 became culture negative while taking the drug, only five were culture negative 2 weeks posttherapy. There were no significant adverse reactions.

Ceftriaxone therapy of serious bacterial infections in adults.

We evaluated the efficacy and safety of ceftriaxone in 50 adults with serious infections, usually giving 1 g every 12 h. Of the 35 patients who could be evaluated for clinical efficacy, 15 had failed on previous therapy, 15 had nosocomial infections, and all but 1 had underlying diseases. One patient had three sites of infection. Favorable responses were seen in 34 of 37 infections, including 11 of 13 respiratory tract infections, all 7 urinary tract infections, all 12 skin and soft tissue infections, 1 of 2 bone and joint infections, a catheter-related septicemia, a liver abscess, and an otitis media and externa. Favorable bacteriological responses were seen for 48 of 58 organisms. This included 6 of 7 Staphylococcus aureus strains, 14 of 16 other aerobic gram-positive cocci, 18 of 20 Enterobacteriaceae, 6 of 9 Pseudomonas aeruginosa, and 1 of 2 anaerobes. Peak plasma ceftriaxone levels on day 1 were 152 micrograms/ml by bioassay and 78 micrograms/ml by high-pressure liquid chromatography. Four of the 31 initial isolates of aerobic gram-negative rods developed resistance to ceftriaxone on disk diffusion testing. Diarrhea occurred in 3 of 50 patients. All three had received a higher than usual dose. Drug administration was stopped twice, once for a thrombocytopenia and once for a thrombocytopenia with leukopenia. Neither problem could be attributed exclusively to ceftriaxone. Other adverse reactions were eosinophilia, abdominal pain, inguinal candidiasis, and nonsuppurative phlebitis. Even among debilitated adults, ceftriaxone was safe and effective in a twice daily regimen.

Gram-negative bacteremias. Analysis of factors for clinical assessment of gentamicin resistance.

We reviewed the charts of 163 patients with 183 episodes of Gram-negative bacillary bacteremia to determine a clinical profile that would select patients at high risk for experiencing gentamicin-sulfate-resistant Gram-negative bacillary bacteremia at our hospital. Gentamicin-resistant Gram-negative bacilli were only associated with institution-acquired bacteremia. Among institution-acquired episodes, urinary tract infection, diagnostic or therapeutic procedures of the lower respiratory tract or urinary tract, presence of pneumonic infiltrate on chest roentgenogram, prior therapy with gentamicin, and prior therapy with other antibiotics were significant risk factors. Because only two of the 29 gentamicin-resistant bacteria that were tested against amikacin base were resistant to amikacin, we advocate initial treatment with amikacin for patients with evidence of an institution-acquired Gram-negative bacteremic episode. Gentamicin is still our initial choice for a community-acquired episode.

Chemical injury of the spinal cord of the rabbit after intracisternal injection of gentamicin.

A single intracisternal injection of 0.4 ml of 1.25 and 2.5 percent gentamicin sulfate with preservative to healthy adult rabbits caused acute respiratory paralysis and severe seizure activity initially and paralysis of the limbs subsequently. In the white matter of the upper cervical spinal cord, multiple, minute, disseminated, spongy lesions were observed. They consisted of lysis of axis cylinders, edematous dilatation of myelin sheaths, and loss of astroglia and interfascicular oligodendroglia. Axonal end-bulbs formed at the periphery of the lesions. Clinically and morphologically, 0.025 and 0.25 percent gentamicin sulfate solution did not produce myelopathy. The spinal lesions were distributed differently from those of other chemical myelopathies in that they developed in the deeper white matter with sparing of marginal myelinated fibers. Circumscribed high concentrations and gentamicin, and vulnerability of myelinated axis cylinders and interfascicular oligondendroglia to gentamicin may be the main factors causing these lesions. When gentamicin sulfate without preservative was injected, neutrophil leukocyte infiltration occurred actively in the spongy lesions. In the cervical spinal ganglia some nerve cells underwent cytoplasmic vacuolation. In control animals a single intracisternal injection of saline or preservative did not result in the production of these lesions.

Group B streptococcal infections in adult males.

A 19-month study of group B streptococcal infection was performed to investigate the spectrum of such infections in adult males, the relation of serotypes to clinical illnesses, the effects of previous antibiotic therapy on infection and colonization, and the antibiotic susceptibility pattern of these organisms. Twenty-four patients had definite or possible infections while 41 patients were colonized with group B streptococci. The most frequent infections encountered were pneumonia (ten cases) and soft tissue infections (nine cases). Five infections (21%) were nosocomial in origin. The most frequent serotypes were Ia and II. No correlation of serotype and type of infection was observed. Patients receiving previous antibiotic therapy were significantly more likely to be colonized than infected with group B streptococci. Penicillin was the antibiotic to which these organisms were most susceptible; tetracycline and gentamicin showed the least activity.