Efficacy of an acellular pertussis vaccine in Japan

To assess the efficacy of an acellular pertussis vaccine that has been used in Japan since 1981, 283 patients with pertussis were selected among patients with suspected pertussis seen at hospitals located around the Tokyo Metropolitan area from 1981 to 1983. The survey of secondary cases in household contacts showed that attack rates in children 0 to 6 years of age were 73.1% in unimmunized children, 15.0% in those fully immunized by whole-cell vaccines, and 15.4% in those given acellular vaccines. The efficacy of Japanese acellular pertussis vaccines was 79% and was not different from that of whole cell vaccines.     

Oral hydration solutions: experimental optimization of water and sodium absorption

Eight solutions of potential efficacy for hydration orally, which differed in composition, osmolality, and pH, were tested in an in vivo perfusion system on rat jejunum to assess the rate of water and sodium absorption or secretion. Optimal results were obtained with a preparation of the type recommended by the World Health Organization, containing 60 mEq/L sodium and 111 mM glucose; there was a maximum influx of both water and sodium, which may be ideal for rehydration. It appeared that the critical factor was the molar relationship between glucose and sodium at a 2:1 ratio. Sodium absorption was inversely correlated with glucose concentration in the perfusates. Osmolality and pH may also have a role in the regulation of fluxes across the mucosa. Citrate at concentrations up to 30 mEq/L did not interfere with water absorption. The data presented may thus contribute to a better rationale for the use of orally administered hydration solutions and guidelines for the preparation of more effective ready-to-use solutions.     

Cardiopulmonary abnormalities in severe acute respiratory failure

Serial cardiopulmonary variables were recorded over 4 days in 23 children with severe acute respiratory failure. In all patients, pulmonary artery catheters were inserted within 24 hours of the diagnosis of respiratory failure, and all required greater than 10 cm H2O positive end-expiratory pressure to achieve adequate oxygenation. Eight patients died (35% mortality). Evaluation of systemic hemodynamic variables indicated that survivors had higher blood pressures than nonsurvivors, although neither group was in the hypotensive range. Systemic vascular resistance was lower in the nonsurvivors. Cardiac function as evaluated by cardiac index, right ventricular stroke work index, and left ventricular stroke work index was similar in both groups. Survivors demonstrated elevations in mean pulmonary artery pressure and pulmonary vascular resistance during the first 36 hours, with gradual improvement thereafter. In contrast, pulmonary artery pressure and resistance increased progressively in patients who died. Intrapulmonary shunt fractions remained high in the nonsurvivors despite the use of up to 25 cm H2O PEEP. Cardiac function and oxygen delivery were well maintained in both groups despite the high levels of PEEP.     

Localized intestinal perforations after enteral administration of indomethacin in premature infants

Four very-low-birth-weight infants developed localized intestinal perforations after enteral administration of indomethacin. The clinical picture and histologic findings were unlike those seen in necrotizing enterocolitis.     

Postconceptional age and gentamicin elimination half-life

We examined the correlation between the elimination half-life of gentamicin and postnatal or postconceptional age in 104 infants greater than 24 weeks to less than or equal to 48 weeks postconceptional age. A weak correlation was observed between half-life and postnatal age (R = -0.353). A better correlation existed between postconceptional age and half-life (R = -0.572). A plot of the log of the mean half-life against postconceptional age was virtually linear. We conclude that postconceptional age is a major determinant of an infant's ability to excrete gentamicin, and speculate that the relationship between half-life and decreasing postconceptional age is exponential.     

Impaired granulocyte chemotaxis and increased circulating immune complexes in Kawasaki disease

Our study was carried out to clarify the changes in granulocyte functions and circulating immune complexes in 32 children with Kawasaki disease. Patients were divided into two groups, those with or without coronary aneurysm. In the group with coronary aneurysm, impairment of both granulocyte chemotaxis and phagocytosis was found, together with higher circulating immune complexes and normal intracellular killing activity. In the group without coronary aneurysm, impaired phagocytosis was observed, with normal granulocyte chemotaxis, circulating immune complexes, and intracellular killing activity. No correlation was observed between granulocyte chemotaxis and circulating immune complexes. Impairment of granulocyte chemotaxis and circulating immune complexes may yield pertinent information as to the degree of severity of vasculitis in Kawasaki disease.     

Myopathy and growth failure in debrancher enzyme deficiency: improvement with high-protein nocturnal enteral therapy

Seven patients with debrancher enzyme deficiency and childhood or adolescent onset myopathy, four of whom also had growth failure, received long-term treatment consisting of high-protein enteral infusion overnight and high-protein feeds during the day for periods varying from 8 to 42 months. All patients demonstrated improvement in physical activity and endurance. Improvement in muscle strength was documented in five patients, with reversal of myopathic EMG patterns to normal in two patients and reversal of abnormal ECG findings to normal in one patient. All four patients with growth failure showed dramatic improvement in growth rates. This positive response to high-protein enteral therapy supports the concept that myopathy in debrancher enzyme deficiency is at least partly the result of reversible muscle amino acid depletion.