The role of Acinetobacter baumannii in infections in ventilated preterm infants was evaluated in 15 colonized infants (11 male, 4 female) in a pediatric intensive care unit. These cases were randomly matched by birth weight and gestational age with ventilated non-colonized controls (8 male, 7 female). Case records were reviewed for signs and symptoms of infection. Colonized infants were ventilated significantly longer (p < 0.05) than controls, and had body temperatures of > 37 degrees C for a significantly longer period of time (p < 0.05). No other parameter of infection differed significantly between the groups. The duration of intensive care treatment did not differ between cases and controls, nor did the weight gain during intensive care treatment. No fatalities occurred in either group.

Acinetobacter↗

PubMed1996

Efficacy of acellular pertussis vaccine in early childhood after household exposure.

OBJECTIVE: To evaluate the efficacy of a three-dose primary vaccination with a diphtheria-tetanus tricomponent acellular pertussis vaccine against "typical" pertussis, defined as a spasmodic cough of 21 days or longer with confirmation of Bordetella pertussis infection by culture or serology. DESIGN: Passive monitoring for suspected first household (index) cases of typical pertussis in six areas in Germany comprising 22,505 children vaccinated with study vaccine at 3, 4, and 5 months of age. Blinded, prospective follow-up of household contacts of index cases for incidence and progression of pertussis. SETTING: Six areas in Germany with a high incidence of pertussis. SUBJECTS: Four hundred fifty-three households with index cases comprising 360 evaluable contacts eligible for analysis of vaccine efficacy. MAIN OUTCOME MEASURE: Vaccine efficacy from attack rates of pertussis in household contacts classified by vaccination status. RESULTS: Of the 173 nonvaccinated household contacts, 96 developed typical pertussis, compared with seven of 112 contacts vaccinated with acellular pertussis vaccine. Vaccine efficacy was consequently calculated to be 88.7% (95% confidence interval, 76.6% to 94.6%). Protection did not wane until at least the time recommended for booster vaccination. None of the analyzed potential confounding factors--age, socioeconomic status, erythromycin treatment, household composition, center effect, and selection bias--influenced study results in favor of the vaccine. CONCLUSIONS: Under conditions of intense household exposure, primary vaccination with acellular vaccine protected against pertussis until at least the time recommended for booster vaccination. The vaccine can be expected to be equally or more effective in settings with lower infectious pressure.

Bordetella pertussis↗

PubMed1996

Host defense within the urinary tract. I. Bacterial adhesion initiates an uroepithelial defense mechanism.

Uroepithelial defense has ben suggested to contribute to the local host resistance against ascending urinary tract infection. The cellular mechanism, however, is not known. In this study, bacterial growth was measured under the direct and indirect influence of uroepithelial cells. To study if a specific ligand-receptor interaction is required for uroepithelial cell (UEC) activation, isogenic Escherichia coli mutants expressing either mannose-sensitive, mannose-resistant (p), or mannose resistant (s) pili were tested for their capacity to induce the UEC defense mechanism. The antibacterial effect of UEC was abolished either by performing coculture in chambers with a fluid-permeable membrane which separates UEC from bacteria or by inhibiting membrane contact using the antiadherence factor pentosane polysulfate. No difference between the various types of pili could be shown. All E. coli strains adhered comparably to the UEC and were subsequently suppressed in their growth. Even a "naked" mutant without expression of common pili showed a similar behavior. In conclusion, bacterial growth suppression depends on direct contact between the UEC and bacteria, but is independent of common pili expressed on E. coli.

Adolescent↗

PubMed1996

Host defense within the urinary tract. II. Signal transducing events activate the uroepithelial defense.

It has been shown previously that the interaction between uroepithelial cells (UEC) from healthy donors and adherent. Escherichia coli suppresses bacterial growth in vitro. The following study was performed to investigate the nature of membrane signal transduction mechanisms involved in this process. UEC/E. coli cocultures were established in the presence of substances known to modulate transmembranous signals. Inhibition of calcium flux, either by calcium channel-blocking substances or by a calmodulin antagonist, depressed the antibacterial UEC function of "healthy" UEC. In contrast, receptor/ligand-induced stimulation of G-proteins, activation of the adenylate cyclase, and the increase of intracellular cyclic AMP levels by cytoplasmatic phosphodiesterase did not increase the antibacterial capacity of healthy UEC. However, the antibacterial function of defense-deficient UEC from patients with recurrent idiopathic urinary tract infection could be reconstituted by this treatment to almost normal levels. In conclusion, the antibacterial UEC defense function is activated by transmembranous signals from bacteria attached to the host cell surface. Activation involves the adenylate cyclase pathway. Activation of the phosphoinositol pathway may contribute to intracellular calcium fluxes.

Bacterial Adhesion↗

PubMed1996

Clinical experience of a tricomponent acellular pertussis vaccine combined with diphtheria and tetanus toxoids for primary vaccination in 22,505 infants.

OBJECTIVES: To assess the safety and tolerability of 12 lots of SmithKline Beecham Biologicals' diphtheria-tetanus-tricomponent acellular pertussis vaccine (DTaP) in a large cohort of 22,000 vaccinees, with detailed analyses of reactivity, immunogenicity, and immune response to pertussis toxin in subsets. METHODS: In a prospective, double-blind, multicenter trial in Germany, 22,505 healthy infants received three vaccinations of DTaP at age 3, 4, and 5 months. Serious adverse events were followed for 1 month after each vaccination, and neurologic events for 1 year or longer. Serum IgG antibodies were assayed before vaccination and 1 month after vaccination. RESULTS: After 67,000 doses, 153 serious adverse events (0.23%) were reported, 8 considered possibly related, and 5 related to vaccination, including 1 hypotonic-hyporesponsive episode. Incidence rates of sudden infant death syndrome (7; 0.01%) or acute neurologic events (20; 0.030%) were no higher than expected and not considered to be related to vaccination. Redness and swelling of 20 mm or greater occurred after 44 (0.6%) and 40 (0.6%) of the 7270 doses, respectively, and high fever (> 39.5 degrees C) in 6 (0.08%) subjects within 48 hours of vaccination. In the immunogenicity analysis of 580 infants, 98% responded to pertussis toxin, 96% to filamentous hemagglutinin, and 98% to pertactin. In an additional 5712 infants, the response rate to pertussis toxin was 99%. CONCLUSIONS: In a large cohort of 22,505 infants vaccinated, SmithKline Beecham Biologicals' tricomponent DTaP vaccine was shown to be safe, well-tolerated, and immunogenic for all component antigens.

Diphtheria-Tetanus-Pertussis Vaccine↗

PubMed1992