Aztreonam in the prevention and treatment of infection in neutropenic cancer patients

Piperacillin/tazobactam plus ceftazidime versus sulbactam/ampicillin plus aztreonam as empirical therapy for fever in severely neutropenic pediatric patients

BACKGROUND

The efficacy and safety of piperacillin/tazobactam plus ceftazidime (PIPC/TAZ+CAZ) versus sulbactam/ampicillin plus aztreonam (SBT/ABPC+AZT) as empirical therapy for febrile neutropenia were assessed in children with hematologic disease and solid tumor.

PROCEDURE

A prospective randomized study was performed to evaluate the clinical response of 70 febrile episodes in the PIPC/TAZ+CAZ arm and 64 evaluable febrile episodes in the SBT/ABPC+AZT arm of the study. Clinical efficacy was evaluated at 120 hours, with treatment outcome criteria defined as follows. Success was defined as disappearance of fever, clinical improvement, eradication of the infecting organism, and maintenance of a response for at least 7 days after discontinuation of treatment.

RESULTS

An infection was documented microbiologically in 14 episodes (20%) in the PIPC/TAZ+CAZ arm and in 8 episodes (13%) in the SBT/ABPC+AZT arm. The success rate was 57.1% in the PIPC/TAZ+CAZ arm and 62.5% in the SBT/ABPC+AZT arm (P>0.05). No major adverse effects were observed in the study.

CONCLUSIONS

PIPC/TAZ+CAZ and SBT/ABPC+AZT are effective and safe for initial empirical treatment of febrile episodes in neutropenic pediatric patients. The clinical efficacy of SBT/ABPC+AZT is equivalent or superior to that of PIPC/TAZ+CAZ, the effect of which is already proven against febrile neutropenia. Therefore, SBT/ABPC+AZT may be a treatment of choice for febrile neutropenia in pediatric cancer patients.

Piperacillin plus aztreonam for treatment of neutropenic fever

BACKGROUND

A combination of beta-lactam plus an aminoglycoside is the most frequently used regimen for febrile episodes in neutropenic cancer patients. However, aminoglycoside-related toxicity occasionally makes this regimen difficult to use as the first-line drug therapy. In the present study, we chose aztreonam as the alternative to aminoglycoside in combination with piperacillin for neutropenic fever in pediatric patients and we evaluated its effectiveness.

METHODS

A total of 31 febrile episodes in 16 patients with malignant neoplasms were evaluted. Piperacillin (200 mg/kg per day) plus aztreonam (150 mg/kg per day) were administered intravenously following a routine fever work-up.

RESULTS

The overall response rate was 67%. The response rate when neutrophil count was less than 100/mm3 was 63%. The side effects were mild and rare. In three patients, all of the microbiologically documented infections were caused by alpha-streptococcus, which required a change in the regimen.

CONCLUSIONS

A combination of piperacillin and aztreonam provides an effective and non-toxic regimen for first-line therapy in febrile patients with neutropenia. In contrast, the results of the present study suggest the need for caution with regard to alpha-streptococcus infections.

Evaluation of aztreonam in the treatment of serious gram-negative infections in a university hospital in Saudi Arabia

The efficacy and safety of aztreonam were evaluated in an open trial at King Khalid University Hospital, Riyadh, Saudi Arabia. A total of 45 critically-ill adult patients were enrolled in the study. All patients with documented Gram-negative infection were treated with aztreonam as monotherapy. Antibiotics active against only Gram-positive and/or anaerobic organisms were allowed. Twenty cases were clinically evaluable. Eleven had lower respiratory tract infections (pneumonia), 3 had urinary tract infections, and 6 had septicemia. Clinical signs and symptoms, cultures and other laboratory profiles were assessed prior to treatment, at 4-6 days during treatment and within 2-3 days of the end of therapy (usually 7-15 days). Nineteen out of 20 (95%) had a satisfactory clinical response. All cases with septicemia and urinary tract infections were microbiologically cured. The overall microbiological response rate was 90%. Fifty-five percent of all infections were caused by Pseudomonas aeruginosa. Two patients with Gram-negative pneumonia due to P. aeruginosa did not respond microbiologically to aztreonam therapy. No serious adverse events requiring discontinuation of aztreonam therapy were reported. No mortality occurred.

Platelet-activating factor induces intestinal necrosis, but not septic shock, in germ-free and specific-pathogen-free rodents

Platelet-activating factor (PAF) was injected into conventional mice, endotoxin-resistant mice (C3H/HEJ), conventional rats, germ-free rats and specific-pathogen-free (SPF) mice. The PAF resulted in significant necrosis and damage to the small intestines of all the animals tested. In general, the frequency and severity of the lesions were similar in all groups. All the conventional rats and mice, as well as the endotoxin-resistant HEJ mice, were dead 18 h after the injection of the PAF, while all the germ-free rats and the SPF mice survived. These data demonstrate that development of massive intestinal lesions, in the absence of aerobic bacteria, is not sufficient to cause the death of the host from septic shock and endotoxaemia.