Microbiome is not linked to clinical disease severity of familial Mediterranean fever in an international cohort of children.

OBJECTIVES: The severity of familial Mediterranean fever (FMF) may vary in different areas, suggesting a role for environmental factors. We analysed the composition of gut microbiota among children with FMF and healthy controls from Turkey and the USA and determined its effect on disease severity. METHODS: Children with FMF with pathogenic MEFV mutations and healthy controls from Turkey and the USA were enrolled. FMF disease activity was evaluated with the Autoinflammatory Disease Activity Index (AIDAI). Gut bacterial diversity was assessed by sequencing 16S rRNA gene libraries. RESULTS: We included 36 children from Turkey (28 patients with FMF, 8 healthy controls), and 21 patients and 6 controls from the USA. In the Turkish group, 28.6% of patients had severe disease, while 13.3% of US group patients had severe disease. As expected, we observed substantial differences between the gut microbiota of children from the two geographic regions, with Turkish patients and controls exhibiting higher relative abundances of Bacteriodia, while US patients and controls exhibited higher relative abundances of Clostridia. Alpha- and betadiversity did not differ significantly between FMF patients and controls, and neither was predictive of disease severity within each geographic region. We observed differences between FMF patients and controls in the relative abundance of some bacterial taxa at the amplicon sequence variant (ASV) level, but these differences received mixed statistical support. CONCLUSIONS: Among an international cohort of children with FMF, we did not find a strong effect of gut microbiota composition on disease severity. Other environmental or epigenetic factors may be operative.

A Case Series of Smallpox Vaccination-Associated Myopericarditis: Effects on Safety and Readiness of the Active Duty Soldier.

Myopericarditis following smallpox vaccination is a documented side effect with increasing incidence since reestablishing mandatory vaccination for deploying military personnel. After the ACAM2000 smallpox vaccine replaced the Dryvax smallpox vaccine, the rate of myopericarditis increased 50-fold.We describe six case reports of active duty soldiers who presented to the emergency department complaining of chest pain shortly after receiving routine pre-deployment vaccinations to include smallpox. All were hospitalized and became non-deployable after developing smallpox vaccination-associated myopericarditis.Some cases of smallpox vaccination-associated myopericarditis are diagnosed in soldiers in austere environments, which have led to the soldier being removed from the mission for months at a time. This can be avoided by having all soldiers who receive the smallpox vaccine screened for clinical evidence of myopericarditis at 30 days after receiving the vaccine. Contributing to the increasing rate of myopericarditis as well as the negative impact on soldier medical readiness, the continued use of the current ACAM2000 smallpox vaccine should be monitored.