Study objective: To determine the outcome of outpatient treatment of febrile infants 28 to 89 days of age with intramuscular administration of ceftriaxone.
Design: Prospective consecutive cohort study.
Setting: Urban emergency department.
Patients: Five hundred three infants 28 to 89 days of age with temperatures greater than or equal to 38 degrees C who did not appear ill, had no source of fever detected on physical examination, had a peripheral leukocyte count less than 20 x 10(9) cells/L, had a cerebrospinal fluid leukocyte count less than 10 x 10(6)/L, did not have measurable urinary leukocyte esterase, and had a caretaker available by telephone. Follow-up was obtained for all but one patient (99.8%).
Intervention: After blood, urine, and cerebrospinal fluid cultures had been obtained, the infants received 50 mg/kg intramuscularly administered ceftriaxone and were discharged home. The infants returned for evaluation and further intramuscular administration of ceftriaxone 24 hours later; telephone follow-up was conducted 2 and 7 days later.
Results: Twenty-seven patients (5.4%) had a serious bacterial infection identified during follow-up; 476 (94.6%) did not. Of the 27 infants with serious bacterial infections, 9 (1.8%) had bacteremia (8 of these had occult bacteremia and 1 had bacteremia with a urinary tract infection), 8 (1.6%) had urinary tract infections without bacteremia, and 10 (2.0%) had bacterial gastroenteritis without bacteremia. Clinical screening criteria did not enable discrimination between infants with and those without serious bacterial infections. All infants with serious bacterial infections received an appropriate course of antimicrobial therapy and were well at follow-up. One infant had osteomyelitis diagnosed 1 week after entry into the study, received an appropriate course of intravenous antimicrobial therapy, and recovered fully.
Conclusions: After a full evaluation for sepsis, outpatient treatment of febrile infants with intramuscular administration of ceftriaxone pending culture results and adherence to a strict follow-up protocol is a successful alternative to hospital admission.