Increased Toll-like receptor 4 expression in infants with respiratory syncytial virus bronchiolitis.

The fusion protein of the respiratory syncytial virus (RSV) binds to the pattern recognition receptors, TLR4 and CD14, and initiates innate immunity response to the virus. The aim of the study was to investigate the expression of TLR4 on peripheral blood lymphocytes and monocytes in peripheral blood of infants in both acute and convalescent phase of RSV bronchiolitis (n = 26). In addition, TNF-alpha expression in lipopolysaccharide-stimulated monocytes was also assessed. The results showed TLR4 to be expressed predominantly by monocytes in both sick infants and controls. During the acute phase of infection monocytes up-regulated TLR4 in eight infants, which returned to the levels recorded in controls 4-6 weeks from infection. There was no difference in the percentage of TNF-alpha secreting monocytes. Of the clinical parameters tested, minimal oxygen saturation was found to correlate negatively with this expression in the group of infants with increased TLR4. Additional studies are under way to correlate this finding with the outcome of the immune response to RSV.

Predominant type-2 response in infants with respiratory syncytial virus (RSV) infection demonstrated by cytokine flow cytometry.

Acute RSV infection in infancy may produce some asthma-like symptoms and may be followed by a recurrent wheeze later in childhood. It has been proposed that RSV infection stimulates type-2 cytokine responses, resembling those found in atopy and asthma. Peripheral blood cells were obtained from RSV-infected infants (n = 30) and healthy controls (n = 10). After in vitro restimulation of the cells, intracellular IL-4 and interferon-gamma (IFN-gamma) were measured by flow cytometry. The cells from RSV-infected infants produced more IL-4 and less IFN-gamma than those from healthy controls. IL-4 production was more frequent in CD8 than in CD4 cells, and the bias toward IL-4 production was greatest in infants with mild infections, whereas IFN-gamma production increased with disease severity. Our conclusions are that RSV infection is associated with IL-4 production in peripheral T cells, and that peripheral blood in infants with severe disease may be depleted of cytokine-producing cells.

Clinical and epidemiological aspects of respiratory syncytial virus lower respiratory tract infections.

This paper has analyzed respiratory syncytial virus lower respiratory tract infections in 201 hospitalized children. In children with wheezing, erythrocyte sedimentation rate (ESR) was significantly higher in those with pneumonia than with syndroma pertussis, while the white blood cell (WBC) count was significantly lower in patients with bronchitis than in those with bronchiolitis and syndroma pertussis. Bronchodilatators were applied in 75.6% and corticosteroids in 20% of patients. Ten patients were ventilated. Fatal disease outcome was observed in one infant. Twelve consecutive-year study of respiratory syncytial virus (RSV) infections showed that 27.3% of these diseases were bronchiolitis and pneumonia.

Short-term treatment of pertussis with azithromycin in infants and young children.

A prospective, open, noncomparative study was conducted to assess the efficacy and safety of azithromycin given once daily for 3 or 5 days to eradicate Bordetella pertussis from the upper respiratory tract of infants and young children. Seventeen children received azithromycin in a dose of 10 mg/kg on day 1 followed by 5 mg/kg once daily for four consecutive days, and 20 were given 10 mg/kg once daily for 3 days. Seven days after the initiation of therapy, 33 of 35 (94.3%) patients had negative cultures for Bordetella pertussis. On day 14, cultures from all 34 evaluable patients were negative. These findings suggest that a controlled, comparative study of erythromycin versus short-term administration of azithromycin is justified.

Antigenic and genomic diversity of central European respiratory syncytial virus strains.

Thirty-two RSV strains recovered during the winter months of 1987/88 to 1993/94 from hospitalized children in Vienna, Austria and Zagreb, Croatia were analysed for antigenic and genetic variations. Twenty-nine of the 32 isolates investigated belonged to group A and 3 to group B, with the majority of infections caused by subgroup A1 (21 of 29). Restriction endonuclease mapping of PCR products derived from parts of the N and G gene of 18 group A strains identified 3 distinct lineages, very similar to those defined by analysis of recurrent epidemics in Birmingham, United Kingdom during the same period. Results of this study provide further information on the global pattern of RSV and show that very similar viruses are present simultaneously in widely separated areas.

Lactate and glucose in cerebrospinal fluid heavily contaminated with blood.

To simulate a traumatic lumbar puncture, blood was added to 33 normal cerebrospinal fluid (CSF) specimens. A hypothesis was tested if the CSF glucose and CSF lactate were unchanged after contamination with blood. Lactate and glucose here measured in both normal and blood-stained CSF. The estimated contamination of the normal CSF with red cells ranged from 84000 to 676500 cells per cubic millimeter. CSF lactate was unchanged by the addition of blood (P = 0.8), whereas CSF glucose was significantly higher in the blood-stained CSF (P = 0.0005). Therefore, the determination of lactate levels in the CSF heavily contaminated with blood could be useful in differentiating viral from bacterial meningitis.

[Review of the present status of prevention, prophylaxis and therapy of pertussis and parapertussis]. / Osvrt na danasnje postavke prevencije, profilakse i terapije pertusisa i parapertusisa.

Whooping cough is endemic throughout the world. It becomes epidemic every 4-5 years (Yugoslavia 3-4 yrs). In Europe its incidence ranges from 0.4 (Hungary) to even 59/100.000 inhabitants (Rumania; Yugoslavia 28), with a general letality of 0.1% (infants: 1%; 75% children who die are younger than one yr). Only 5-10% cases are supposed to be registered. A low socioeconomic status is more and more emphasized as the principal risk factor. Its transmission rate is high (home contacts: 80-100%); infectivity lasts five weeks, disease from the beginning of incubation to the sanation lasts 50-60 days. Female children are more frequently affected. The term "Pertussis syndrome" is more end more used because a similar disease can be caused by various agents (B. pertussis; B. parapertussis: 5%-20%-30% cases; B. bronchiseptica rarely; adenoviruses, RS virus, parainfluenza virus, influenza A and B virus, HSV, CMV, EBV, entero-, adeno-, corona-, rota-viruses; chlamydiae and mycoplasmae). Prior to introducing vaccination, 95% of population have had a typical or atypical form of pertussis. Its differential diagnosis includes pneumonias of various etiology, bronchitis, bronchiolitis during an acute respiratory infection, bronchial asthma, cystic fibrosis, tuberculosis and lymphadenopathy. Morbidity in USA was reduced by vaccination from 157 to 0,5-1,5/100,000 inhabitants; in SR Croatia it was six times reduced in period 1959-1970. According to the official sources 81% of children in Croatia and Yugoslavia get primovaccinated; the 80% level is generally accepted as a rational goal. Immunization schedules differ from country to country. Local and general reactions after combined vaccines are mostly caused by pertussis component.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of antibodies to hepatitis A virus among urban children aged 0-7 years in Yugoslavia.

In a study of the prevalence of hepatitis A virus antibody in urban Yugoslav children aged 0-7 years, 18.2% were positive; most of them were only a few months old. The maternal origin of antibody in these very young children could be inferred from the rapid decrease of antibody during the first 5-7 months of life, following which period until the age of 7 years, there was no significant increase in the proportion with antibody. It was concluded that the age range included in this study (0-7 years) does not represent a time of life when most urban Yugoslav children come into contact with hepatitis A virus.