Amelia Romano

Selective Depression of Interferon-γ and Granulysin Production with Increase of Proliferative Response by Vγ9/Vδ2 T Cells in Children with Tuberculosis

Vgamma9/Vdelta2 T cells can contribute to protective immune response against Mycobacterium tuberculosis, although the extent to which and mechanisms by which they could actually protect against human tuberculosis remain unclear. We have previously reported that Vgamma9/Vdelta2 T cells from tuberculin purified protein derivative (PPD)-positive children, either healthy or affected by different clinical forms of tuberculosis, strongly proliferate to different phosphoantigens in vitro, whereas Vgamma9/Vdelta2 T cells from PPD-negative healthy subjects proliferate very poorly. We report here that Vgamma9/Vdelta2 T cells from tuberculous children have an increased proliferative activity, but decreased interferon (IFN)-gamma production and granulysin expression. After successful chemotherapy, the Vgamma9/Vdelta2 T cell proliferative response strongly decreased, whereas IFN-gamma and granulysin production consistently increased. Disease-associated changes in Vgamma9/Vdelta2 T cell effector functions in patients with tuberculosis are consistent with the possibility that these T cells may play a protective role in immune response against M. tuberculosis infection.

Clinical and laboratory findings of boutonneuse fever in Sicilian children.

Abstract The spectrum of signs and symptoms of 645 consecutive children diagnosed from 1984 to 1996 with boutonneuse fever (BF), a mild rickettsial disease caused by Rickettsia conorii endemic in the Mediterranean basin, are reported. The major clinical features were fever (97.2%), exanthema (96.1%) and “tache noire” (71.8%). The large series examined permitted the authors to observe some rare or disregarded clinical features of the disease: cases with papulovesicular exanthema, reported previously only in adults who had been infected by R. conorii in Africa; and cases in which the only symptom was an isolated lymphadenopathy. ConclusionR. conorii infection should be considered in patients with lymphadenopathy who live in or have travelled to an endemic area, even when other, more specific features, are not present. Also pox-like vesicular lesions may be caused by this organism, awaiting confirmation by using culture techniques instead of serology. The serological confirmation of BF by immuno fluorescent antibody test is possible only late in the illness.

Ligand-Specific αβ and γδ T Cell Responses in Childhood Tuberculosis

The alphabeta and gammadelta T cell responses were analyzed in the peripheral blood of children affected by active tuberculosis (TB) and in healthy children who tested positive (PPD+) or negative (PPD-) for purified protein derivative. PPD+ healthy and diseased children responded equally well to PPD in vitro. In contrast, only 18% of PPD+ TB patients responded to peptide p38G derived from the 38-kDa protein of Mycobacterium tuberculosis. Analysis of the whole gammadelta T cell population and of its Vgamma9/Vdelta2 subset showed similar frequencies in PPD+ children with TB and in healthy PPD+ and PPD- children. Vgamma9/Vdelta2 cells from children with TB responded to 5 different phosphoantigens similarly to those from healthy PPD+ children, but healthy PPD- children responded very poorly. Chemotherapy had contrasting effects on the tested lymphocyte population, represented by increase of alphabeta and decline of Vgamma9/Vdelta2 T cell responses. T cell responses in childhood TB may be similar to those in adult TB.

Epidemiology of Toxoplasma and CMV serology and of GBS colonization in pregnancy and neonatal outcome in a Sicilian population.

BackgroundAim of our study is to analyze the immunological status in pregnancy for two main TORCH agents, Toxoplasma and Cytomegalovirus (CMV), and the results of group B streptococcus (GBS) screening, assessing the risk for congenital infection in a population from Palermo, Italy.MethodsWe retrospectively analyzed the medical records of all inborn live newborns who were born in our division during 2012, gathering information about the mother, the pregnancy and neonatal hospitalization at birth. Whenever data were available, we categorized the serologic status of the mothers for Toxoplasma and CMV. We also considered the results of rectal and vaginal swabs for GBS. We compared the results in Italian and immigrant mothers. The neonatal outcome was evaluated in all cases at risk.ResultsPrevalence of anti-Toxo IgG antibodies was 17.97%, and was significantly higher in immigrant women (30% vs 16.4% in Italian women; p = 0.0008). Prevalence of anti-CMV IgG antibodies was 65.87%. Again, it was significantly higher in immigrant women (91.4% vs 62.5%, p = 3.31e-08). We compared those data with a previous study performed in our hospital in 2005–2006, and found that the prevalence of anti-Toxoplasma and anti-CMV antibodies in our population has remained stable, both in the immigrant and in the local population. Seroconversion rates and neonatal infections were rare: no seroconversions were observed for Toxoplasma, 4 seroconversions for CMV. One neonatal Toxoplasma infection and two neonatal CMV infections were documented. In some cases with dubious patterns or probable persistence of IgM, we performed additional tests and follow-up. Vaginal and rectal swabs were positive for GBS in 7.98% of cases, with no significant difference between the Italian and the immigrant population. No GBS neonatal sepsis was documented.ConclusionsThe prevalence of Toxoplasma IgG antibodies in pregnant women was low in our population, if compared with European countries and with other parts of Italy, and is significantly higher in immigrant women. The prevalence of CMV IgG antibodies was intermediate if compared to other countries, and it was higher in immigrant women. GBS positivity was low, and comparable in Italian and immigrant mothers. Neonatal infection was rare for all these agents.

Epidemiological assessment of Respiratory Syncytial Virus infection in hospitalized infants, during the season 2005–2006 in Palermo, Italy

ObjectivesRespiratory Syncytial Virus (RSV) is the leading cause of hospitalization for lower respiratory tract infections (LRTI) in young children worldwide.We evaluate the epidemiological and clinical patterns of RSV infection in infants hospitalized for LRTI in in Palermo, South Italy, Sicily.MethodsWe collected the demographic details of infants hospitalized to G. Di Cristina Childrens Hospital in Palermo for LRTI between November 2005 and May 2006. We also included all cases occurred in newborns hospitalized in the Neonatal Intensive Care Unit (NICU) Of Palermo.ResultsDuring the studied period, 335/705 hospitalized infants for LRTI were enrolled in the study. The trend of hospitalization started in late winter and lasting until May 2006 with an epidemic peak in spring. 178/335 infants tested for viral infection showed RSV disease. Three cases occurred in preterm newborns hospitalized from birth in NICU. The likelihood to be RSV+, rather than RSV negative (RSV-) was higher for infants < 6 months and lower for infants with history of breast feeding (P < 0.05). RSV infection was associated with a higher likelihood to be admitted to intensive care unit and to a longer hospitalization and oxygen therapy.ConclusionThe study shows that, in Sicily, RSV is an important cause of LRTI in infants. The seasonal distribution shows that both LRTI and RSV infections peak in late spring, in contrast to Northern Italy. Our data could help to define the regional appropriate start of prophylactic interventions.

Anti-16-kilodalton mycobacterial protein immunoglobulin M levels in healthy but purified protein derivative-reactive children decrease after chemoprophylaxis

ABSTRACT Serum responses against Mycobacterium tuberculosis HSP16 were determined for children with tuberculosis (TB) and for healthy purified protein derivative (PPD)-positive and PPD-negative children. Immunoglobulin G (IgG) and IgM responses were higher for TB patients than for other groups. After chemotherapy, IgM and IgG responses decreased for TB patients and PPD-positive subjects. Monitoring of anti-M. tuberculosis HSP16 responses could assist in the management of pediatric TB.

Investigation and management of Toxoplasma gondii infection in pregnancy and infancy: a prospective study

Aim:Toxoplasma gondii infection during pregnancy poses a serious risk to the fetus, therefore timely and accurate diagnosis is essential. The aim of this study was to estimate the frequency of congenital infection via evaluating mothers immunological status and the possibility to improving the diagnostic and therapeutic approaches.Methods:Eighty five mothers with Toxoplasma seroconversion and their offspring were enrolled (among them, 2 spontaneous abortions were documented in the first trimester). Prenatal PCR diagnosis was carried out on 50 patients (60%), with 7 positive cases (14%). Morphological ultrasound scanning revealed anomalies in one fetus. Long-term follow-up included general physical examinations, serological status tested using Western blot, neuro-radiological, ophthalmologic and neurologic examinations, psychological and developmental tests, visual evoked potential tests and audiology tests, as well as anti-Toxoplasma treatment regimes.Results:Fourteen (17%) of the infants were infected at one-year serological follow-up. Chi-square for linear trend of vertical transmission from the first to the third trimester was significant (P=0.009). Western blot analysis showed IgM and IgA in half of the infected infants. In 69 uninfected infants, anti-Toxoplasma IgG immunoblot analysis excluded infection within the 3 months in 18 infants (26%) and in the others within 6 months of life. The most relevant instrumental findings are described.Conclusion:Western blot analysis may help to evaluate infection within the 6 months of life. The accuracy of ultrasound imaging to determine the brain damage in the fetus and newborns is doubtful, and should be combined with MR imaging. Multistep approaches can improve the timing of postnatal follow-up.

Children, parents and Respiratory Syncytial Virus in Palermo, Italy: prevention is primary

A study was conducted to describe the characteristics of the Respiratory Syncytial Virus (RSV) infection cases occurring in the season 2006—7 in Palermo, Italy, and to evaluate the parents’ knowledge and behaviours concerning prevention and control of acute respiratory infections (ARIs). All children aged between 0 and 2 years, admitted for a lower respiratory tract infection (LRTI) between October 2006 and May 2007, were enrolled in the study. Data were collected about demographic and household characteristics. Furthermore, their parents were asked to compile a structured questionnaire on transmission, prevention and management of ARIs in children. A total of 198 children with a diagnosis of LRTI were enrolled. Ninety-eight (62.0%) of 157 were positive for RSV. Parents were generally aware of transmission of ARIs through sneezing and/or coughing, but less through contaminated objects or hands. Nationality, age and education level of parents and also the age of the patients proved to be associated with some self-reported knowledge and behaviours. Only 24 (12.3%) of the 195 respondents had received advice from GPs or paediatricians about good hygiene practices. It seems essential to implement public health interventions promoting behavioural changes aimed at the primary prevention of ARIs at the community level.

Serum leptin and interleukin-6 levels in pediatric patients with HIV.

Recent therapeutic approaches have improved the prognosis of children with HIV. Many new efforts could be involved in their quality of life and therefore could need additional diagnostic strategies. Leptin regulates pubertal development; furthermore a continuous immune stimulus, as in chronic infectious diseases, can enhance leptins secretion by the action of cytokines such as interleukin (IL)-6. To clarify this role in patients infected with HIV, we assayed leptin and IL-6 and evaluated the influence of HIV severity on its secretion. IL-6 (380.5 +/- 257.6 pg/ml; range: 22-900 pg/ml) showed a significant correlation with leptinemia, HIV-1 RNA, and viremia related to the stage of HIV disease. The difference in leptinemia from a control group (3 +/- 3.2 ng/ml; range: 1-12 ng/ml in HIV patients; 6.72 +/- 8 ng/ml in the controls) did not reach statistical significance, nor did it correlate with pubertal stage, BMI, viremia, CD4 or anti-retroviral therapy. There was a statistically significant correlation between leptinemia and the stage of the HIV disease, and with IL-6 level. We want to stress the role of immunological factors in enhancing leptin secretion.

Lymphocyte apoptosis in children with central nervous system tuberculosis: a case control study

BackgroundStudies of the apoptosis mechanisms involved in the pathogenesis of tuberculosis have suggested that Mycobacterium tuberculosis can actively interfere with the apoptosis of infected cells. In vivo studies have been performed in adult populations but have not focused on this process in children. In the present study, we analyzed spontaneous T lymphocyte (PBT) apoptosis in the peripheral blood of children with central nervous system tuberculosis (CNS TB), before and after chemotherapy, and compared the results with healthy controls.MethodsA case-control study was conducted from January 2002 to June 2009. It included 18 children with CNS TB and 17 healthy controls. Spontaneous apoptosis of PBTs, including CD4+, CD8+ and CD8+/CD28+ T cells, was evaluated after 24 and 72 h of culture in complete medium, using the Annexin V detection test. Analysis was conducted before and after chemotherapy, and expression of the apoptotic markers CD95 (Fas) and Fas ligand (FasL) was evaluated.ResultsHigher percentages of apoptotic T cells and CD4 lymphocytes were isolated from children with acute phase CNS TB than from children in the control group (p < 0.05). This difference significantly decreased after 60 days of specific treatment. In children with CNS TB, high levels of Fas ligand expression were detected in lymphocyte populations, associated with a high percentage of Fas positive cells, before and after treatment. In contrast to the CD4+ apoptosis profile, we did not find any significant difference in total CD8+ cell apoptosis between children with acute phase disease and the control group. However, the percentage of apoptotic CD8+/CD28+ T cells was significantly higher in the children with acute phase disease than in the healthy controls.ConclusionsOur findings indicate that CNS TB in pediatric patients increases the sensitivity of CD4 and CD8+/CD28+ T cells to apoptosis, suggesting a hypoergic status of this infection. This could play a key role in the immunopathogenesis of this complicated form of TB. Interestingly, specific chemotherapy is able to normalize both apoptosis sensitivity and T-cell activation.