Scleroderma (systemic sclerosis)

Systemic sclerosis is a condition in which the immune system and connective tissue interact in a way that leads to thickening and hardening of the skin, and in its systemic form, involvement of internal organs including the lungs, heart, kidneys, and digestive tract. Current understanding describes both an inflammatory autoimmune process and an overgrowth of collagen, the protein that gives connective tissue its structure, driving the fibrosis seen in affected organs.

A 2023 analysis of global data estimated the worldwide incidence at roughly 8.6 per 100,000 person-years and prevalence around 19 per 100,000 people, translating to an estimated 1.47 million people affected globally, though rates vary widely by region and are notably higher in North America and Europe than in East Asia. Systemic sclerosis is markedly more common in women and typically diagnosed in mid-adulthood.

Common signs

Thickening and tightening of the skin, often starting in the fingers and hands, along with Raynaud's (fingers turning white or blue in the cold). People may notice puffy or stiff fingers, heartburn and swallowing trouble, and, depending on organ involvement, shortness of breath or other signs.

This is a plain-language summary for orientation, not a diagnosis. Mechanisms are described as current understanding, not settled fact. Work with your own clinician for your care.