BCGitis in IPEX syndrome

We present the case of a male infant diagnosed with IPEX (immune dysregulation, polyendocrinopathy, enteropathy, and X-linked) syndrome who presented a generalized rash with a BCG site reaction several months after vaccination. Erythema and induration at BCG site might be due to BCG which is a known complication of inborn errors of immunity with susceptibility to mycobacterial infection. However, in our patient this dermatological manifestation might be secondary to immune dysregulation, given the important role of Tregs and Th17 cells in mycobacterial immunity, similar to that observed in Kawasaki disease patients.