Pediatric sarcoidosis comprises a spectrum of childhood granulomatous inflammatory conditions. Pathological hallmark of the disease is granuloma formation that is seen in the affected tissues and almost any organ or system can be involved. There are two forms of pediatric sarcoidosis. One is seen in older children and the clinical picture is very similar to that of adult sarcoidosis and the other one is seen in early childhood. Sarcoidosis in early childhood can be divided as Blau syndrome (familial form) and early onset sarcoidosis (sporadic form). In both of the diseases there is a defect in the NOD2/CARD15 gene. The typical triad of early onset sarcoidosis is polyarthritis, dermatitis and uveitis. Interferon-γ receptor 1 deficiency is caused by defects in the IFNγR1 gene and non-tuberculosis mycobacterial pathogens are the leading causes of infections that start in early childhood. Herein we report a patient who presented with the symptoms of early onset sarcoidosis and also had partial interferon-γ receptor 1 deficiency that presented with BCG-osis. In addition to anti-mycobacterial treatment, methotrexate and prednisolone were used in therapy.

Keywords: BCG-osis, early onset sarcoidosis, interferon-γ receptor 1 deficiency, macrophage activation syndrome, skeletal involvement