Objective:

To evaluate the effectiveness and safety of botulinum toxin (BTX) injections for refractory ischemic digital complications in systemic sclerosis.

Approach:

• Study Design: Systematic review and individual participant data meta-analysis of studies from MEDLINE, Embase, and Scopus.
• Participants: 119 patients with acute digital ischemia, ischemic digital ulcers, or gangrene, predominantly female (75%) with a mean age of 49 years.
• Outcomes: Primary outcome was complete response (CR) defined as resolution of ischemia or ulcer healing; secondary outcomes included adverse events and time to response.

Key Findings:

• BTX was associated with high CR rates: 93.1% for ischemia, 90.1% for ulcers, and 87.5% for gangrene.
• Adverse events were infrequent, with transient muscle weakness (7.6%) and injection site pain (5.9%) being the most common.
• Younger age and autoimmune etiology were associated with faster response.

Interpretation:

Limitations:

• No associated factors reached statistical significance in multivariable models.
• Further prospective trials are needed to confirm long-term effectiveness and standardize administration protocols.

Conclusion:

Sources:

• JAMA Dermatology Study