Therapeutic plasma exchange, the removal of harmful components from plasma in blood, may be an effective therapy for patients with systemic sclerosis (SSc) who develop Raynaud’s phenomenon, according to a new study analysis.
The findings will be presented at the American College of Rheumatology (ACR/ARHP) Annual Meeting, Nov. 11-16 in Washington D.C., in the presentation “Therapeutic Plasma Exchange for the Treatment of Raynaud’s and Digital Ulcers in Systemic Sclerosis: A Systematic Review.”
Patients with SSc often develop Raynaud’s phenomenon. The disease can occur when cold temperatures or emotional stress causes blood vessels in the hands and feet to narrow for a period of time, decreasing blood flow to those limbs and leading to cell death. About 50 percent of patients develop digital ulcers due to impaired blood flow to the fingertips.
Current therapies target the blood vessels to improve blood flow and reduce the risk of digital ulcers. Therapies include three main approaches:
- Vasodilators are drugs that help relax and widen the blood vessels. Examples include Adalat, Ventavis and Viagra.
- Vasoconstrictor antagonists are drugs that help prevent blood vessels spams caused by sudden narrowing. Tracleer is an example.
- Other therapies that reduce blood vessel spams by blocking (Botox) or removing the nerves that trigger the spasms (digital sympathectomy).
Currently, none of the treatments are particularly effective.
Through the new report anaysis, researchers sought to understand whether therapeutic plasma exchange (TPE) could be a viable solution. They reviewed articles about TPE treatment for SSc published between 1978 and 2016. Of 40 papers reviewed, 13 reported effects of TPE on digital ulcers and Raynaud’s phenomenon.
A limited course of TPE treatment appeared to provide marked improvements in Raynaud’s and digital ulcers, blood flow, vessel widening, and certain characteristics of the blood flow for several months.
“Since TPE treatments have no known direct effects on blood vessels, these results suggest that TPE may have an entirely different mechanism of action,” the authors wrote in the report. “(But) a common finding was that a single course of a few weekly TPE treatments (typically four) had significant, long-lasting impact on both Raynaud’s symptoms as well as healing digital ulcers.”
The results caused additional questions among the researchers. For instance, how TPE exerts its beneficial effect, what is the nature of abnormal blood flow in SSc, and whether it could be a result of other disease processes.
“We recommend that a randomized, double blind, placebo-control study of TPE that includes measurements of blood rheology be conducted to better understand these effects,” the authors wrote.