Liver abscess complicated by diaphragm perforation and pleural empyema leads to the discovery of interleukin-1 receptor-associated kinase 4 deficiency.

Interleukin-1 receptor-associated kinase 4 (IRAK-4) deficiency predisposes to severe invasive bacterial infections in infancy and early childhood, often with a fatal course caused by a defect in Toll-like receptor and interleukin-1 receptor signaling. Despite severe invasive infections, acute phase responses are often diminished. We report the successful treatment of a child with multiple liver abscesses, diaphragm perforation and pleural empyema, accompanied by strong acute phase responses as a unique presentation of IRAK-4 deficiency.