The relationship betweenJAK2(V617F) mutation and dermatomyositis-a case report and literature review

The JAK family (JAK1, JAK2, JAK3, and TYK2) have recently emerged as a potential therapeutic management in controlling severe and refractory dermatomyositis. Meanwhile, the progress in the discovery of JAK blockers is significant, with an increasing number of selective JAK inhibitors reported and some are in or prepare for clinical trials. However, the importance of each JAK in dermatomyositis is unclear, which is critical for a comprehensive understanding of dermatomyositis and significant for forming mechanism-based strategy. Here, we presented a case with clinically amyopathic dermatomyositis and essential thrombocytosis with a somatic constitutive active mutation ofJAK2(V617F). The coexistence of these two uncommon diseases attracted us to investigate their underlying relationship. To this end, we characterized the clinical course and laboratory findings of this patient. Particularly, we correlatedJAK2(V617F) mutation burden in affected peripheral blood subset with clinical activity score of dermatomyositis. Based on our observation, we concluded that these two diseases are independent disorders, andJAK2(V617F) mutation burden is irrelevant to the severity of dermatomyositis. Finally, we reviewed the literature and summarized them with a thorough discussion.

Automated summary

The study presented a case of clinically amyopathic dermatomyositis and essential thrombocytosis with a somatic constitutive active mutation of JAK2(V617F). The research investigated the relationship between these two rare diseases and concluded that they are independent disorders, with JAK2(V617F) mutation burden being irrelevant to the severity of dermatomyositis.