Allergies, body mass, and hospitalization due to arbovirus infection: A prospective surveillance study in Machala, Ecuador.

Dengue, chikungunya, and Zika are arboviruses that cause 390 million infections annually. Risk factors for hospitalization are poorly understood. Communities affected by these diseases have an escalating prevalence of allergies and obesity, which are linked to immune dysfunction. We assessed the association of allergies or body mass with hospitalization for an arbovirus infection. From 2014 to 2017, we recruited participants with a clinical diagnosis of arbovirus infection. Arbovirus infections were laboratory-confirmed and allergies were self-reported. Mid-upper arm circumference (MUAC), weight, and height were measured. We used two logistic regression models to assess the relationships between hospitalization and allergies and between hospitalization and body mass (MUAC for participants <20 years old and body mass index (BMI) for adults ≥20 years old). Models were stratified by age group and adjusted for confounders. For allergies, 41 of 265 were hospitalized. There was no association between allergies and hospitalization. For body mass, 34 of 251 were hospitalized. There was a 43% decrease in hospitalization odds for each additional centimetre MUAC among children (aOR 0.566, 95% CI 0.252-1.019) and a 12% decrease in hospitalization odds for each additional BMI unit among adults (aOR 0.877, 95% CI 0.752-0.998). Our work encourages the exploration of the underlying mechanisms.

Evaluation of immunogenicity of the T cell costimulation modulator abatacept in patients treated for rheumatoid arthritis.

OBJECTIVE: The immunogenicity of abatacept, a selective costimulation modulator, administered intravenously, was assessed across Phase II and III trials in patients with rheumatoid arthritis (RA). METHODS: Two direct-format enzyme-linked immunosorbent assays evaluated antibody responses [whole abatacept molecule (CTLA-4 and Ig portion) and CTLA-4 portion only (Assay A)] in the Phase II trials. During the Phase III trials and 2-year open-label periods, a similar, but more sensitive, Assay B was employed. Serum samples collected prestudy, during treatment, and 56 and/or 85 days following the last dose were evaluated. Seropositive samples with anti-CTLA-4 reactivity and sufficiently low drug levels were further characterized for neutralizing activity (cell-based bioassay). RESULTS: A total of 2237 patients with both pre- and post-baseline serum samples were eligible for assessment. Of these, 62 (2.8%) patients demonstrated an anti-abatacept or anti-CTLA-4 response, determined using either Assay A or B. Using the more sensitive Assay B, 60 of 1990 patients (3.0%) demonstrated an antibody response to the whole abatacept molecule (n = 41, 2.1%) or the CTLA-4 portion (n = 19, 1.0%). Of the 1764 RA patients evaluated in the Phase III studies, 203 discontinued therapy and had sera collected 56 and/or 85 days after discontinuation. Patients who discontinued had a higher incidence of immunogenicity versus patients who did not discontinue (7.4% vs 2.6%, respectively). Of 20 patients positive for anti-CTLA-4 reactivity, 13 were eligible for assessment with the neutralization bioassay. Of these, 8 patients exhibited neutralizing activity. Seroconversion occurred with no adverse safety outcomes or effect on pharmacokinetic parameters. No consistent pattern was observed between antibody response and loss of efficacy (American College of Rheumatology 20 and Health Assessment Questionnaire responses). CONCLUSION: Abatacept was associated with a low incidence of immunogenicity in patients with RA and lacked any adverse sequelae.