Serum proteomics reveals hemophagocytic lymphohistiocytosis-like phenotype in a subset of patients with multisystem inflammatory syndrome in children.

Children with Multisystem Inflammatory Syndrome in Children (MIS-C) can present with thrombocytopenia, which is a key feature of hemophagocytic lymphohistiocytosis (HLH). We hypothesized that thrombocytopenic MIS-C patients have more features of HLH. Clinical characteristics and routine laboratory parameters were collected from 228 MIS-C patients, of whom 85 (37%) were thrombocytopenic.

Introduction of Heated Cow's Milk Protein in Challenge-Proven Cow's Milk Allergic Children: The iAGE Study.

The introduction of baked milk products in cow's milk (CM) allergic children has previously been shown to accelerate induction tolerance in a selected group of children. However, there is no standardized baked milk product on the market. Recently, a new standardized, heated and glycated cow's milk protein (HP) product was developed.

[When is a tall child too tall?].

3 children presented with tall stature. A 14-year-old girl of 179.6 cm was found to be within her target height range and was treated with oestrogen.

Complement dependency of splenic localization of pneumococcal polysaccharide and conjugate vaccines.

The immune response to polysaccharides is initiated when polysaccharides bind complement factor C3d, and these polysaccharide-C3d complexes subsequently localize on splenic marginal zone B cells strongly expressing CD21 (complement receptor 2). Infants and children under the age of 2 years have low or absent expression of CD21 on their marginal zone B cells, and consequently do not adequately respond to polysaccharides. In contrast, polysaccharide-protein conjugate vaccines are able to induce antibodies at this young age.

[Four infants with congenital cystic malformation of the lung: different routes of diagnosis and forms of management].

In four neonates, two boys and two girls, congenital cystic malformation of the lung was diagnosed. Two cases were diagnosed during prenatal ultrasound investigation. One of the patients recovered by a wait-and-see policy, one after antibiotic treatment and two following surgical removal of the diseased lung sections.

After chemotherapy, functional humoral response capacity is restored before complete restoration of lymphoid compartments.

Chemotherapy has, besides the beneficial effects, several adverse effects. Suppression of the immune system is one of the most important problems. Infections caused by encapsulated bacteria like Streptococcus pneumoniae are responsible for a major part of infectious problems during and after treatment.

Breath holding spells in a 3-day-old neonate: an unusual early presentation in a family with a history of breath holding spells.

Breath holding spells are common in childhood. They peak about 2 years of age and abate by 5 years of age; they are rare before 6 months of age. We report a case of cyanotic breath holding spells starting at the age of 3 days.

Concentration and avidity of anti-Haemophilus influenzae type b (Hib) antibodies in serum samples obtained from patients for whom Hib vaccination failed.

Haemophilus influenzae type b (Hib) conjugate vaccines are extremely effective in protecting infants and children from invasive Hib infections; however, vaccine failures do occur. The anti-Hib antibody production was studied both quantitatively and qualitatively in 12 patients who experienced Hib failure, all of whom had normal serum immunoglobulin concentrations and all of whom were without clinical risk factors for invasive Hib disease. Both anti-Hib antibody concentration and immunoglobulin-G2 anti-Hib antibody avidity were significantly lower in patients who experienced Hib failure, at onset of disease and after reconvalescence, when compared with controls.

Pneumococcal conjugate vaccines overcome splenic dependency of antibody response to pneumococcal polysaccharides.

Protection against infections with Streptococcus pneumoniae depends on the presence of antibodies against capsular polysaccharides that facilitate phagocytosis. Asplenic patients are at increased risk for pneumococcal infections, since both phagocytosis and the initiation of the antibody response to polysaccharides take place in the spleen. Therefore, vaccination with pneumococcal polysaccharide vaccines is recommended prior to splenectomy, which, as in the case of trauma, is not always feasible.

Immunological characterization of conjugated Haemophilus influenzae type b vaccine failure in infants.

Infant vaccination with conjugated Haemophilus influenzae type b (Hib) vaccine is highly effective in protecting against invasive Hib infections, but vaccine failures do occur. Twenty-one vaccine failures are reported since the introduction of the Hib conjugate vaccine in The Netherlands. Of the 14 evaluable patients, 6 children showed no antibody response to Hib polysaccharide in convalescent-phase serum (immunoglobulin [Ig] G anti-Hib level <1.

Fcgamma receptor polymorphisms determine the magnitude of in vitro phagocytosis of Streptococcus pneumoniae mediated by pneumococcal conjugate sera.

Fcgamma receptors show two genetically determined polymorphisms: the biallelic FcgammaRIIa-R131 and -H131 polymorphism and the NA1/NA2 FcgammaIIIb polymorphism. Using 10 pre- and postconjugate vaccination sera from adults, we analyzed in vitro phagocytic capacities of three different combinations of polymorphonuclear leukocyte FcgammaR allotypes: those homozygous for the H131 and NA1 allotype, those homozygous for the R131 and NA2 allotype, and those heterozygous for both receptors. For pre- and postvaccination sera, mean phagocytosis levels for the homozygous H131/NA1 allotype were 4 -fold higher than for the homozygous R131/NA2 allotype.

[[Immunology in medical practice. XVIII [correction of XVII]. Children with recurrent airway problems: asthma is not always the cause].

Three children, two boys aged 16 and 11 years and a girl aged 16 years, with symptoms resembling asthma had been treated for years with inhaled corticosteroids and beta 2-sympathicomimetics without satisfactory results. It was found that the antibody production after vaccination with 23-valent pneumococcal vaccine was impaired. The symptoms diminished during maintenance treatment with antibiotics in two children and with intravenous immunoglobulins in one.

Pneumococcal conjugate vaccine primes for polysaccharide-inducible IgG2 antibody response in children with recurrent otitis media acuta.

Children with frequent recurrent episodes of otitis media may have a deficient IgG2 antibody response to polysaccharide antigens. Five otitis-prone children were vaccinated with heptavalent pneumococcal conjugate vaccine. While all had an IgG1 antibody response to all pneumococcal serotypes included in the conjugate vaccine, the IgG2 response, especially to serotypes 6B, 9V, 19F, and 23F, was poor.

Regulatory T cells in the antibody response to Haemophilus influenzae type b polysaccharide.

An in vitro culture system for the induction of an antipolysaccharide response was used to study the cellular interactions which determine the magnitude and nature of this B-lymphocyte response. Healthy adult volunteers were vaccinated with the Haemophilus influenzae type b polysaccharide (PRP)-tetanus toxoid (TT) conjugate vaccine. Optimal in vitro anti-PRP and anti-TT antibody responses were obtained when B cells were cultured with equal amounts of T cells.

Infant B cell responses to polysaccharide determinants.

Newborns and infants up to the age of 1.5-2 years of age are unable to produce antibodies to bacterial capsular polysaccharides. As a consequence, children up to the age of 2 years have an increased susceptibility for infections with encapsulated bacteria.

[Invasive infection with Haemophilus influenzae type b in spite of complete vaccination].

Five patients, 4 boys and 1 girl aged 13-41 months, developed invasive Haemophilus influenzae type b (Hib) disease (2 epiglottitis, 3 meningitis) despite full (or at least 3 times) vaccination. At admission as well during convalescence, 3 out of 5 had IgG anti Hib antibody levels < or = 5 U/ml. Serum immunoglobulin levels, including IgG subclasses, as well as complement were normal in all cases.

Properties of human anti-group B streptococcal type III capsular IgG antibody.

The group B streptococcus is the commonest cause of bacterial infection in the newborn. In an attempt to prevent these infections, various vaccines are in development, most of which contain at least one of the capsular carbohydrates of the bacterium. We present new detailed data on the natural human antibody response to the type III capsular carbohydrate as we believe it is important to ascertain equivalent data for any new candidate vaccine in order to predict efficacy.

Solid-phase antigen density and avidity of antibodies detected in anti-group B streptococcal type III IgG enzyme immunoassays.

Two enzyme immunoassays which measure anti-group B streptococcal type III capsular carbohydrate IgG antibodies were compared. One utilised poly-L-lysine conjugated coating antigen while the other used tyraminated coating antigen. Both carbohydrate antigens appeared to be antigenically identical but the poly-L-lysine based assay gave significantly lower values for some sera.