Recurrent infection with genetically identical pneumococcal isolates in a patient with interleukin-1 receptor-associated kinase-4 deficiency.

Interleukin-1 receptor-associated kinase (IRAK)-4 deficiency is a rare primary immunodeficiency disorder characterized by severe, invasive infections with Streptococcus pneumoniae. Using the PFGE technique a genetic linkage was found between two S. pneumoniae serotype 14 isolates causing arthritis and meningitis at 3 and 5(1/2) years of age, respectively, in a boy with IRAK-4 deficiency. This finding suggested that patients with IRAK-4 deficiency may harbour persistent strains of pneumococci. Alternatively, reinfection with strains from close contacts of the patient might cause recurrent invasive disease. It is proposed that eradication of pneumococci from the nasopharynx, and immunization of household contacts may prevent recurrent infection in IRAK-4-deficient patients.