High renal crisis, interstitial lung disease prevalence with systemic sclerosis sine scleroderma

Key takeaways:

• Nearly 10% of patients with systemic sclerosis had systemic sclerosis sine scleroderma, a subtype without skin fibrosis.
• The patients had a higher prevalence of interstitial lung disease and renal crisis.

Dermatologists should be aware of cutaneous findings in patients with systemic sclerosis sine scleroderma due to the association of internal organ dysfunction, according to a study.

“Systemic sclerosis (SSc) is a rare connective tissue disease characterized by the association of autoimmune features with vascular manifestations and, in the majority of patients, fibrosis of the skin and internal organs, predominately heart, lungs and kidneys,” Alain Lescoat, MD, PhD, of the department of internal medicine and clinical immunology at University of Rennes in Rennes, France, and colleagues wrote. “There is a high heterogeneity among patients with SSc regarding the presence and severity of skin and visceral involvement.”

Systemic sclerosis sine scleroderma (ssSSc), a subset of SSc, has visceral manifestations like other forms of SSc, but does not have skin fibrosis.

Researchers conducted a longitudinal observational cohort study using the EUSTAR database that included 4,263 patients with SSc, of which 376 (8.8%; mean age, 55.3 years; 91.8% women) had ssSSc.

Compared with patients with two other subtypes of SSc, limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc), patients with ssSSc had a lower prevalence of digital ulcers and puffy fingers; however, interstitial lung disease prevalence was similar in ssSSc and lcSSc and significantly higher compared with dcSSc.

More than 40% of those with ssSSc had lung fibrosis and renal crisis was prevalent in nearly 3% of patients with ssSSc, which was similar to the prevalence in dcSSc.

“Skin telangiectasias in patients with ssSSc were associated with important visceral manifestations, such as elevated systolic pulmonary arterial pressure on echocardiography in univariate analysis or intestinal symptoms and diastolic dysfunction in univariate and multivariate analysis,” the authors wrote.

This analysis suggests that this subset of SSc should not be neglected and dermatologists should be aware of the visceral manifestations of the disease.

“Acknowledging the specific prognosis and phenotype of ssSSc is among the necessary steps toward precision medicine and updated classification for SSc, and the term systemic sclerosis should be systematically preferred to scleroderma when designating this systemic autoimmune disease to reflect the risk of organ involvement even in patients without skin fibrosis, ie, sine (without) scleroderma,” the authors wrote.