Dysthrophic calcification in Systemic Sclerosis – Intralesional Injections of Sodium Thiosulfate may have significant Positive Effects on your patients

Abstract

Purpose
To describe our three year experience with intralesional injection of sodium thiosulphate as treatment for dystrophic calcification (DC) in patients suffering from Systemic Sclerosis (SSc), overlap syndrome and dermatomyositis.

Methods
Between September 2016 and October 2019, selected SSc, overlap syndrome, and dermatomyositis patients with problematic DC were systematically and prospectively recruited to treatment once a week for four weeks and follow up after 12-16 weeks. During each visit, data concerning DC size, ulceration, inflammation, and both patient and physician global score (1-10) (PtGA and PhGA) were collected on customized data sheets. The DC lesions were injected with sodium thiosulfate 150mg/ml on top or in the upper part of the lesion by the same clinician. After treatment, the lesion was covered up with a pressure distributing plaster for at least 24 hours.

Results
Among 43 patients offered treatment, 38 patients, 33 women and 5 men, had one or more problematic DC treated with intralesional sodium thiosulfate. The total number of treatments was 463. The patients had between 1 and >200 DC lesions and at each session between 1 and 22 lesions were treated.

A total of 36 series consisting of 4 treatments were performed in 29 patients, 26 women and 3 men. Among these patients, 18 had systemic sclerosis of limited cutaneous type (lcSSc), 8, 2, and 1 patient had systemic sclerosis of diffuse cutaneous type (dcSSc), overlap syndrome, and dermatomyositis respectively.

The average PtGA and PhGA before treatment was 6.4 and 6.1 respectively. A significantly decrease of the average PtGA and PhGA score was observed week by week and after the third treatment the average decrease in PtGA and PhGA was 2.7 and 2.5 respectively (p<<0.001). Almost all patients experienced intense pain during and after injection (up to several minutes), but otherwise side effects were few and not serious.

Conclusions
We find that intralesional sodium thiosulfate injections have positive effect with limited side effects on selected SSc patients with problematic DC. We recognize the limitations of the study design leaving plenty of questions to be addressed. It is our clinical impression that both patient, lesion, and clinician related factors may influence the outcome of the treatment. We hope that our treatment regimen may inspire physicians to consider sodium thiosulfate injections as a possible treatment for troublesome DC before referring to surgical interventions.