Measles-specific antibodies loss after a single dose of MMR vaccine in children with oligo-articular JIA on methotrexate treatment: a single-center case-controlled study.

Novel treatments have revolutionized the care and outcome of patients with juvenile idiopathic arthritis (JIA). Patients with rheumatic diseases are susceptible to infections, including vaccine preventable ones, due to waning immunity, failing immune system and immunosuppressive treatment received. However, data regarding long-term immunological memory and response to specific vaccines are limited. Assessment of the impact of methotrexate (MTX) treatment on measles-specific-IgG titers, in children with oligo-JIA previously vaccinated with Measles Mumps Rubella (MMR) vaccine (1 dose); by evaluating the persistence of antibodies produced after measles vaccination while on immunomodulating treatment at 0, 12 and 24 months. Single-center controlled study including 54 oligo-JIA patients and 26 healthy controls. Seroprotection rates and measles-specific-IgG titers were measured by ELISA and were expressed as GMCs (Geometric Mean Concentrations).The two groups had similar demographic characteristics, vaccination history and immunization status. Seroprotection rates were adequate for both groups. Nonetheless, measles GMCs were significantly lower in the oligo-JIA compared to the control group at one (p = 0.039) and two years' follow-up (p = 0.021). Children with oligo-JIA on MTX treatment appeared to have lower measles-specific-IgG titers. Further studies are required to assess the long-term immunity conveyed by immunizations given at an early stage in children with rheumatic diseases on synthetic Disease Modifying Antirheumatic Drugs (sDMARDs) and to assess the need for booster doses to subjects at risk.

Quantiferon-Cytomegalovirus assay: A potentially useful tool in the evaluation of CMV-specific CD8+ T-cell reconstitution in pediatric hematopoietic stem cell transplant patients.

Pediatric HSCT recipients are at high risk for CMV reactivation due to their immature immune system and therapy following transplantation. Reconstitution of CMV-specific T-cell immunity is associated with control and protection against CMV. The clinical utility of monitoring CMV-specific CMI to predict CMV viremia in pediatric HSCT patients using the Quantiferon-CMV (QIAGEN® ) test was investigated prospectively. Thirty-seven pediatric allogeneic HSCT recipients were enrolled from 3/2010-6/2012. CMV viremia was detected via weekly real-time PCR. The Quantiferon-CMV test was conducted pretransplant, early after transplantation, 30, 90, 180, 270, and 360 days post-transplantation. The incidence of CMV viremia was 51% (19/37) with half of the episodes within ≤30 days post-transplant. Fifteen patients showed CMV-specific immunity (average of 82 days). The cumulative incidence of CMV reactivation in patients who developed CMV-specific immunity was lower than those who did not (15% vs 53%; P = .023). The ROC statistical analysis showed that the AUC was 0.725 in predicting viremia, for Quantiferon-CMV test. In this cohort, the Quantiferon-CMV assay was a valuable method for identifying pediatric HSCT patients at high risk for CMV viremia, suggesting potential clinical utility to individualize patient's management post-transplant.