Israel Medical Association Journal

STING-associated vasculopathy with onset in infancy (SAVI) is a rare monogenic type I interferonopathy that may present with heterogeneous clinical manifestations and mimic common inflammatory disorders of childhood. We report the first familial case of SAVI in Israel, affecting a father and daughter carrying an identical pathogenic gain-of-function TMEM173 variant. The daughter initially presented with features fulfilling criteria for rheumatoid factor-positive juvenile idiopathic arthritis (JIA), later developing growth failure and progressive interstitial lung disease. In contrast, the father developed adolescent-onset inflammatory arthritis, subsequently lung disease, and a severe infectious neurological complication during treatment. This case highlights marked intrafamilial phenotypic variability, the diagnostic challenges posed by atypical inflammatory arthritis and the importance of genetic testing in treatment-refractory or systemic disease. Our findings underscore both the benefits and limitations of JAK inhibition in SAVI, particularly with respect to pulmonary disease and growth outcomes.

Background: Intra-articular corticosteroid injection (IACI), a common procedure in juvenile idiopathic arthritis, is usually associated with anxiety and pain. In a previous study, we concluded that nitrous oxide (NO₂) provides effective and safe sedation for such procedures. Following the introduction of medical clowns in our hospital, we added them as an integral part of the team performing IACI.

Objectives: To prospectively evaluate the effect of a medical clown on pain perception during intra-articular corticosteroid injection for juvenile idiopathic arthritis using NO₂ conscious sedation.

Methods: Patients scheduled for IACI first met and interacted with the medical clown. During the procedure, the rheumatologist and the medical clown worked in parallel to create distraction. NO₂ was administered. The patient, parent, physician, medical clown and nurse completed a visual analog scale (0–10) for pain. Change in heart rate ≥ 15% was recorded to evaluate physiologic response to pain and stress.

Results: A total of 46 procedures were performed in 32 children: 23 girls, 9 boys, with a mean age of 10.9 ± 3.6 years. The median visual analog scale pain score for the patients, parents, physicians, medical clown and nurses was 2, 2, 1, 1 and 1, respectively. Five patients had increased heart rate and experienced increased pain.

Conclusions: Active participation of a medical clown during IACI with nitrous oxide for juvenile idiopathic arthritis further decreases pain and stress and results in a positive patient experience.