Mononuclear cell reactivity to food allergens in neonates, children and adults.

A model of antigen-specific T-cell proliferative responses based on reciprocal patterns of responses to dietary and inhalant allergens has been suggested, the former being frequent in infancy but rare in adults, whereas the latter are preserved and expand between infancy and adulthood. We have evaluated the age-related variations of mononuclear cell reactivity to food allergens. The cord blood mononuclear cells (CBMC) of 30 neonates without family history of atopy and the peripheral blood mononuclear cells (PBMC) of 20 healthy children and of 40 healthy adults were stimulated in vitro with beta-lactoglobulin (BLG) or ovalbumin (OVA) and the cultures were harvested after 7 days. Neonates, children and adults were compared for the percentages of positive responses and for the magnitude of response. Adult subjects showed significantly lower percentages of positive responses and reduced magnitude of response than those observed in neonates and children either in BLG or in OVA cultures. We have not observed a decrease of food allergen mononuclear cell reactivity between neonates and children for the frequency of positive responses. The magnitude of response of neonates was significantly lower than that of children in BLG cultures. Our results seem to confirm the loss of mononuclear cell reactivity to food allergens in adult age. However, other reports show conflicting data. We suggest that a rigorous standardization of the methodological steps of in vitro mononuclear cell stimulation with allergen is necessary.

In vitro IgE synthesis in neonates with different family history of atopy.

In this study we want to correlate family history of atopy and in vitro synthesis of IgE, IL4 and IFN gamma in 5 neonates with biparental (group A), 5 with uniparental (group B) and 5 with absent family history of atopy (group C). An aliquot of neonatal blood mononuclear cells (NBMC) was incubated in presence of PHA in combination with the phorbol ester acetate (TPA). The supernatants of cultures were harvested after 48-72 hours of incubation and stored at -20 degrees C until testing for lymphokine production by ELISA kits. Only one neonate of group B showed detectable in vitro synthesis of IL4 (45 pg/ml) after PHA + TPA stimulation. All the others failed to produce detectable levels either of IL4 or IFN gamma. Another aliquot of NBMC was cultured in the presence of saturating concentrations of rhIL4 for 48 h. After this pre-incubation step, the non-adherent cells were cultured in the presence of: 1) rhIL4; 2) rhIL4 + anti-IL4 antibody (Ab); 3) rhIL4 + anti-IFN gamma Ab; 4) rhIFN gamma, 5) rhIFN gamma + anti-IFN gamma Ab + rhIL4; 6) PWM + rhIL4; 7) unstimulated culture. The supernatants of these cultures were tested for their IgE content. In general, spontaneous IgE production by NBMC was very low, rhIL4 did not induce a significant increase of IgE synthesis. The other modalities of stimulations did not produce significative changes. We did not observe significative differences among the three groups of neonates. On the basis of our results, we conclude that NBMC aren't able to produce significative amounts of IgE in vitro either spontaneously or after IL4 stimulation. This test and the evaluation of IL4 and IFN gamma in vitro production aren't useful markers of atopy predisposition.

[Intracranial hemorrhage in congenital factor II deficiency]. / Emorragia endocranica nel deficit congenito del fattore II.

A case of congenital defect of factor II is reported. It concerns a newborn with a not traumatic haematoma due to congenital hypoprothrombinaemia, which is rarely described in scientific literature.

Interleukin 2 proliferative response by cord blood mononuclear cells of term and preterm neonates.

The results of previous studies on the proliferative response of resting cord blood mononuclear cells (CBMC) of term neonates to human recombinant interleukin 2 (hrIL-2) are contrasting. Some authors have reported a good and others a poor response. In our study we have obtained a significant reactivity, compared with the response of resting peripheral blood mononuclear cells (PBMC) of adult subjects, of resting CBMC to varying quantities of hrIL-2 in the absence of any known mitogenic or antigenic stimuli. Most responding cells was CD3 positive. Both CD4-positive and CD8-positive cells responded. However, we observed a more marked increase of the percentage of the CD4-positive T cells and a clear reduction of the percentage of the CD21-positive cells (B-lymphocytes) testing CBMC rather than PBMC of the adult subjects. The percentage of the NK cells was reduced in both the categories of subjects. Moreover, we have examined the reactivity to hrIL-2 of CBMC of preterm neonates. The results showed that this response is low. The peculiar level and kinetic of CBMC proliferative response to hrIL-2 are discussed.

Immunodeficiency and plasma zinc levels in children with Down's syndrome: a long-term follow-up of oral zinc supplementation.

To evaluate the possible effect of zinc treatment on immune disorders in children with Down's syndrome (DS), 38 noninstitutionalized DS children were investigated. Twenty-four patients (63.2%) had plasmatic zinc levels lower than 0.70 microgram/dl ("hypozinkemic," LZn) and 14 patients (36.8%) had levels higher than 0.75 microgram/dl ("normozinkemic," NZn). No correlation was found between the zinc deficiency and recurrence and/or intensity of infections. The absolute numbers of peripheral lymphocytes, the percentages of B lymphocytes, total T cells, and serum IgG, IgA, and IgM levels did not differ between the DS children and the controls. Eight (21%) patients had CD4+ T cell counts below the lowest value for the controls. Seventeen (44%) DS patients had increased levels of CD8+ T cells. The mean percentage of Leu 7+ cells in DS subjects (22.8 +/- 12.9%) was significantly higher than that in controls (15.8 +/- 4.8%) (P less than 0.01). Notably, Ig levels and numbers of lymphocytes in each subset did not show any significant difference in NZn and LZn trisomic subjects. On the contrary the peripheral blood mononuclear cells (PBMCs) from LZn DS children showed a significantly lower proliferative response to phytohemagglutinin (PHA) (S.I. = 23.4 +/- 22.4) than that of PBMCs from NZn DS children (S.I. = 46.1 +/- 21.5, P less than 0.01). A significant increase in DNA synthesis was obtained after oral administration of zinc sulfate (20 mg/kg/day, for 2 months). The lymphocyte response to PHA appeared to be normal in all patients up to 6 months after the end of the zinc treatment and it became low in half of the patients 22 months after therapy.

Intravenous immunoglobulin in Diamond-Blackfan anaemia.

Since immunological disorders have been demonstrated in patients with Diamond-Blackfan anaemia (DBA), intravenous immunoglobulins (IVIG) were administered to a 14-year-old girl with DBA and congenital malformations, previously treated with corticosteroids and blood transfusions. No therapeutic effect was observed.

Intravenous immunoglobulin for prophylaxis of neonatal sepsis in premature infants.

The incidence of sepsis, mortality due to sepsis, total mortality, and minor infections was evaluated in a group of 46 premature newborn infants who were treated with intravenous immunoglobulins. They were compared with an untreated control group. No significant differences were observed between the two groups.

Effective high-dose intravenous gammaglobulin therapy for passive immune thrombocytopenia in the neonate.

The second child of a mother with idiopathic thrombocytopenic purpura was given 400 mg/kg per day polyethylenglycol-treated gammaglobulins during the first 5 days of life. Thrombocytes increased from 15 X 10(9)/l to 200 X 10(9)/l within 10 days and remained at this level afterwards.

Varicella arthritis. Report of a case.

A rare case of varicella with bilateral acute arthritis of the knee is described. Clinical features and laboratory results of the patient are briefly compared with those of other sixteen cases previously published. The study of immune response shows a decrease of helper T cells (OKT4+) and an increase of suppressor/cytotoxic T cells (OKT8+) with a normal response of lymphocytes to PHA.

[Neonatal sepsis and perinatal risk factors]. / Sepsi neonatale e fattori di rischio perinatali.

Numerous studies have identified perinatal risk factors of neonatal sepsis. Some authors have attempted to develop a score system and have shown that babies with septicemia usually had a significantly higher score than healthy newborns and infants with other diseases. The aim of our study is to verify the validity of a scoring method based on the following items: maternal disease; e.g. diabetes, severe toxemia, infection; rupture of the membranes more than 24 hours before the delivery; foul-smelling amniotic fluid; complicated delivery; Apgar score less than 7; umbilical catheterization; respiratory distress and other neonatal diagnoses leading to operative procedures. We have evaluated four groups of babies, full-term AGA and SGA and preterm AGA and SGA, 84 with septicemia, 105 with other diseases and 210 healthy newborn infants. None of the perinatal risk factors or neonatal diseases was sufficiently predictive of neonatal septicemia. Only the incidence of umbilical catheterization was significantly higher (p less than 0.01) in preterm AGA (37.1%) and SGA (64.7%) babies with septicemia than in preterm healthy AGA (2.8%) and SGA (7.7%) babies; on the contrary, no statistical differences were found between preterm AGA (37.1%) and SGA (64.7%) infants with septicemia and preterm AGA (42.8%) and SGA (66.6%) infants with other neonatal diseases. A score of 1 was assigned for each of the considered items. In the full-term infants a score of 1 or less was found in 100% of the healthy infants. A score of 2-3 was found in 26% of the septicemic infants and in 42% of the infants with other diseases.(ABSTRACT TRUNCATED AT 250 WORDS)

[Neonatal sepsis caused by coagulase-negative staphylococci]. / Sepsi neonatale da stafilococchi coagulasi-negativi.

All cases of neonatal bacteremia occurring at Neonatal Department of Pediatric Clinic, Catholic University of Rome, from January 1976 to December 1983 were examined retrospectively. Twenty-seven (30%) newborn infants with positive blood cultures for coagulase-negative staphylococcus were identified. Seven (25.9%) of the 27 infants were born at term, 4 AGA and 3 SGA; mean birth weight was 2,804 gm (range 2,280-3,670). All of these neonates had clinical evidence and laboratory signs of sepsis, and one had the cerebrospinal-fluid culture positive for coagulase-negative staphylococcus. In the remaining 20 infants (74.1%) the mean birth weight was 1,445 gm (range 810 - 2,400) and mean gestational age was 32 weeks (range 27 - 36). In 15 of the 20 preterm infants clinical signs of septicemia were associated with positive blood culture, and sixty percent of these had received an umbilical artery catheter. An half of coagulase-negative staphylococci isolated from our neonatal sepsis were DNAse-positive and/or phosphatase-positive and/or mannitol-positive. Two full-term infants, one with Down syndrome and one with cardiac malformation, died at 9 days and at 2 weeks of age, respectively. Three of 15 preterm infants with coagulas-negative staphylococcal septicemia died; deaths were among infants of very low birth weights and immature gestations who had severe respiratory syndrome. These data show that coagulase-negative staphylococcus can be important cause of septicemia in patients with compromised host defenses as newborn infants, and especially in the premature babies receiving invasive procedures.