Once-daily ceftriaxone to complete therapy of uncomplicated group B streptococcal infection in neonates. A preliminary report.

Newborn infants minimally symptomatic with non-central nervous system (CNS) infections due to Streptococcus agalactiae (group B streptococcus [GBS]) and other pathogens may not require skilled nursing care during the entire course of parenteral antibiotic therapy. In 1985, treatment guidelines were made available to private practitioners in Oregon for therapy of newborn infants at low risk of complications from their infections. In 1988, patient data were collected and analyzed retrospectively. Outpatient management during convalescence of 51 infants (21 with culture-positive infections due to GBS) was accomplished with once-daily physician follow-up examinations and IM injection of ceftriaxone. Long-term (greater than or equal to two months) follow-up data were available for 67% of GBS-infected infants, with no complication of infection or significant complication of therapy reported. Outpatient parenteral antibiotic management of selected, low-risk infants may offer the clinician an alternative to hospitalization for a portion of the duration of parenteral antibiotic therapy.

Bacterial endocarditis at a small community hospital.

Clinical features, microbiology, and predisposing factors are described in 56 patients with bacterial endocarditis (BE) treated over a 12-year period at a small community hospital in Hawaii. The average age of patients was 52.0 years. The mean duration of symptoms was 28.8 days (range 1 to 240 days). Streptococci was the most frequently identified causative organism, present in 61% of the cases. Gram-negative bacilli were isolated from six patients (11%). Fourteen patients (25%) required cardiac surgery; the most common condition leading to surgery was severe valvular insufficiency, followed by congestive heart failure and recurrent embolism. Eighty-two percent of the patients in the series survived. The leading causes of death were congestive heart failure and cerebrovascular accidents.

Predominance of T cells that express CD45R in the CD4+ helper/inducer lymphocyte subset of neonates.

Neonates have an increased risk of severe infections. For several in vitro and in vivo immune responses, neonates have been shown to have significant differences when compared to normal adults. To indirectly study immune cellular defects, we compared cell surface markers on cord blood lymphocytes (CBL) from 58 term infants to peripheral blood lymphocytes (PBL) from 17 healthy adults using flow cytometry with standard as well as newly defined monoclonal antibodies (Mab) that distinguish regulatory T cells. CBL had significantly smaller percentages of lymphocytes that express the CD2 and CD8 markers (total T cells, and suppressor/cytotoxic T cells, respectively), although absolute numbers of CD2+ and CD8+ cells were comparable in neonates and adults. CBL and PBL were similar in terms of the percentage of CD4+ cells (helper/inducer T cells), although the absolute numbers of CD4+ cells were higher in CBL than in PBL. The CD4+ population was subdivided into cells bearing the virgin and memory T cell phenotypes using anti-2H4 and anti-4B4 Mab and dual parameter analysis with anti-CD4. Neonates were deficient in the percentage of CD4+, 4B4+ (3.8 +/- 2.8 vs 13.4 +/- 7.5, P less than 0.001), but equivalent to adults in the percentage of CD4+, 2H4+ T cells (21.4 +/- 9.8 vs 18.8 +/- 12.8). In absolute numbers, neonates had fewer CD4+, 4B4+ cells (178 +/- 173 vs 344 +/- 152 cells/microliters, P less than 0.001), but more CD4+,2H4+ cells (978 +/- 572 vs 542 +/- 518 cells/microliters, P less than 0.01) than adults. The predominance of 2H4+ virgin T cells in the CD4 population whose function is associated with that of the induction of suppression rather than the up-regulation of immune responses may contribute to the observed susceptibility of neonates to infection.