Hexavalent vaccines for immunization in paediatric age.

Despite the potential for protection against a broad spectrum of pathogens, the availability of an increased number of effective vaccines could lead to a significant reduction in vaccination coverage as the result of issues with implementation of new vaccines within existing protocols. To overcome these problems, the development of combined vaccines has been promoted. The use of combined vaccines offers a number of potential benefits, including a reduction in the number of patient visits, reduced complications associated with multiple intramuscular injections, decreased costs of stocking and administering separate vaccines, and a lowering of the risk of delayed or missed vaccinations. The hexavalent vaccine includes antigens against diphtheria, tetanus, acellular pertussis (DTaP), hepatitis B (HBsAg), poliomyelitis (P1, P2, P3) and Haemophilus influenzae type B (Hib) infections. The primary goal of this review is to discuss the immunogenicity, efficacy, safety and tolerability of several hexavalent preparations that are either commercially available or still under development.

Assessment of activity of Crohn's disease of the ileum and large bowel: proposal for a new multiparameter MR enterography score.

PURPOSE: We evaluated the diagnostic accuracy of magnetic resonance enterography (MR-E) in assessing Crohn's disease (CD) activity by differentiating acute, chronic and remission stages of disease through a quantitative MR-E assessment. MATERIALS AND METHODS: One hundred patients with a histological diagnosis of CD were studied with MR-E. Intestinal distension was obtained by oral administration of approximately 2 L of a polyethylene glycol solution (PEG). In all cases, the ileum and large bowel were imaged with morphological sequences (heavily T2-weighted single-shot, dual fast-field echo, balanced fast-field echo) and a postcontrast dynamic sequence (T1-weighted high-resolution isotropic volume excitation). Disease activity was assessed according to a multiparameter score (0-8) based on lesion morphology, signal intensity and contrast enhancement. MR-E findings were compared with clinical-laboratory data and disease activity indices [Crohn's Disease Activity Index (CDAI); Inflammatory Bowel Disease Questionnaire (IBDQ)]. Multiple regression analysis was performed by correlating MR-E score, CDAI and IBDQ. Frequencies were then compared using the χ (2) test. RESULTS: MR-E identified inactive disease in 9% of cases, chronic disease in 57% and active disease in the remaining 34%. The most frequently involved bowel segment was the terminal ileum (52%). A statistically significant correlation was found between MR-E score and CDAI (R=0.86; p<0.001) and between MR-E score and IBDQ (R=-0.83; p<0.001). The most suggestive parameter for disease activity was layered bowel-wall enhancement, a finding predominantly present in patients with increased CDAI (≥ 150) and/or local complications (χ (2)=7.13; p<0.01). CONCLUSIONS: MR-E is a noninvasive and diagnostic imaging modality for CD study and follow-up. The MR-E score proposed in this study proved to be useful in assessing disease severity and monitoring response to treatment.