Abstract
Immunodeficiency-related vaccine-derived rubella virus cutaneous granulomatous disease as the initial manifestation of an inborn error of immunity is rare. We present a case of a 17-month-old girl with a skin eruption, which started three weeks after a routine measles, mumps, and rubella vaccination. Immunofluorescence staining and PCR and sequencing confirmed the presence of rubella virus (vaccine strain). Whole exome-based primary immunodeficiency panel revealed a homozygous UNC13D 12-bp deletion, associated with familial hemophagocytic lymphohistiocytosis.