Clinical characteristics of pediatric synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome: the first Chinese case series from a single center.

INTRODUCTION

Pediatric SAPHO syndrome is regarded as the equivalent of chronic recurrent multifocal osteomyelitis or chronic non-bacterial osteomyelitis. This study aimed to evaluate the clinical features and treatment options for Chinese pediatric patients with SAPHO syndrome.

METHOD

We conducted a single-center, retrospective study on a sample of 24 pediatric patients with SAPHO syndrome who were diagnosed at Peking Union Medical College Hospital from April 2014 to August 2018. The demographic, clinical, laboratory, imaging, histological, and therapeutic data were collected and analyzed.

RESULTS

A total of 15 boys and 9 girls were included. The mean age of onset of bone and skin symptoms was 11.7 ± 3.8 and 14.4 ± 2.7 years, respectively. The mean follow-up period was 39.2 months. Seventeen patients had skin manifestations (46% had severe acne, 100% were boys; 21% had palmoplantar pustulosis, 100% were girls). Bone lesions were localized in four of the following major regions: anterior chest wall (42%), mandible (29%), peripheral bones (50%), and spine and sacroiliac joints (21%). Six patients had been treated with non-steroidal anti-inflammatory drugs, 10 with bisphosphonate, 10 with a tumor necrosis factor-α antagonist, and 1 with glucocorticoids, with variable responses. A total of 70% of the patients had complete remission after bisphosphonate or TNF-α antagonist therapy.

CONCLUSION

Pediatric patients with SAPHO syndrome have different characteristics from other cohorts in the sex ratio, frequency of mandibular involvement, and sex distribution of skin lesions. Bisphosphonate and TNF-α antagonists show a favorable response in pediatric SAPHO syndrome treatment. Key points •Being the first study that describes an Asian pediatric SAPHO case series. •Chinese pediatric patients with SAPHO syndrome have different characteristics from Chinese adult patients and Caucasian pediatric patients.