Immunosuppressants, Pulmonary Vasodilators Could Save Lives in Rare PAH Cases

Drugs that suppress the immune system should be used with drugs that dilate the arteries to treat pulmonary arterial hypertension (PAH) associated with adult-onset Still’s disease (AOSD), according to a new study published in the journal Respiratory Medicine Case Reports.

In the study “Pulmonary arterial hypertension secondary to adult-onset Still’s disease: Response to cyclosporine and sildenafil over 15 years of follow-up,” Dr. Doug Helmersen, a respirologist at the Division of Respirology, Department of Medicine, University of Calgary, in Canada and colleagues described the case of a 40-year-old woman who presented with PAH 19 months after AOSD diagnosis.

Although PAH has been associated with several rheumatic conditions and connective tissue diseases such as systemic sclerosis, systemic lupus, and mixed connective tissue disease, AOSD is rarely reported as a cause of PAH. In fact, only eight other cases of PAH associated with AOSD have been reported in literature since 1990 — and all had poor outcomes.

AOSD is a rare inflammatory autoimmune disease characterized by high fever, joint pains, a distinctive salmon-coloured bumpy rash, swollen lymph nodes, and an enlarged liver and spleen. In AOSD patients, the level of liver enzymes, number of white blood cells and iron levels in the blood are all higher than normal. The cause of AOSD is not known.

People with PAH and AOSD have high levels of inflammatory cytokines, including IL-1, IL-6, and tumor necrosis factor-alpha (TNF-α), but how inflammation and aberrant immune response are associated with the development of PAH is not fully understood.

The woman was treated with sildenafil, a PAH-specific pulmonary vasodilator, and cyclosporine, an immunosuppressant therapy. This treatment combination resulted in an excellent clinical improvement of the patient and long-term survival of 15 years.

It is the first reported case of PAH associated with AOSD with such long-term survival, and emphasizes the potential role of immunosuppressants in combination with pulmonary arterial vasodilators for treatment of the condition.