For over thirty years, researchers at the University of Pittsburgh (UPMC) have been observing cases of limited scleroderma, a connective tissue disorder that causes thick hard patches of skin. Scleroderma is also known as systemic sclerosis.
A recent article in MedPageToday reported that a 1990 study of 371 UPMC patients diagnosed with scleroderma tested positive for anti-Th antibodies.
More recently, and most importantly, a study found that thirty-eight percent of patients diagnosed with limited cutaneous scleroderma and anti-Th/To antibodies had pulmonary hypertension. This compares to fifteen percent of comparable patients who did not have the antibodies. In addition, antibody-positive patients had a higher mortality rate.
The disorder consists of a group of rare diseases involving tightening and hardening of the skin. Problems with internal organs, blood vessels, and the digestive system may also develop.
The term localized or “limited” scleroderma refers only to the area of skin involvement. Both scleroderma and limited scleroderma may also affect other organs. Treatments are available to mitigate symptoms, yet there is currently no cure for the disorder.
About Long Term Results
The researchers discovered that long-term results for scleroderma patients had not been determined. The UPMC team referred back to records generated for patients at their referral center between 1980 and 2015. They reviewed the patients’ history during that time period. Out of 3,613 patients tested, 204 were positive for the anti-Th/To antibody.
The team generated 408 controls by pulling the two negative records immediately following a positive case.
Almost ninety-seven percent of antibody-positive cases that were reviewed came under the category of limited scleroderma, compared to fifty-six percent of the antibody-negative controls.
The researchers discovered that there was a significant change in pulmonary hypertension cases during the review.
At the onset of the review, the baseline, there was a total of twenty-six percent of pulmonary hypertension cases. At the same time, nine percent of controls had pulmonary hypertension.
Yet the final follow-up showed an increase of twelve percent in pulmonary hypertension cases and a six percent increase in the control group. Patients with pulmonary hypertension represented two-thirds of both groups.
Cause of Death
Interstitial lung disease (scarring/fibrosis) and pulmonary hypertension accounted for most scleroderma-related deaths.
Dr. Robyn Domsic of UPMC and colleagues viewed the thirty-eight percent pulmonary hypertension rate of antibody-positive patients as extremely significant. The group noted that anti-Th/To testing is currently commercially available.
In conclusion, Dr. Domsic emphasized that patients with limited scleroderma should undergo tests for Th/To antibodies. If found, then monitoring is warranted in order to identify patients who are at high risk of pulmonary hypertension.