The COVID-19 outbreak and rheumatologic skin diseases.

Dear Editor

Global public health is currently challenged with the volcanic spread of coronavirus disease 2019 (COVID‐19). The American College of Rheumatology has announced that there are no current data on the COVID‐19 infection in patients with connective tissue diseases. Hence, extrapolation from the documented literature of other RNA viruses causing connective tissue diseases is our best estimate of how the COVID‐19 virus could affect the rheumatic system. Previous study evaluated the patterns of cross‐reaction of severe acute respiratory syndrome (SARS)‐CoV antigen and antibodies in connective tissue diseases. The patients with systemic lupus erythematosus, systemic sclerosis, mixed connective tissue disease, and rheumatoid arthritis, all showed cross reactions. False‐positive antibody tests were present in samples collected from patients with autoimmune diseases with rheumatic associations. Hence, it is reasonable to keep in mind that there may be a flare of the symptoms of these diseases, including the rheumatologic manifestations.

Genetically susceptible connective tissue diseases like rheumatoid arthritis (RA) have viruses that include coronavirus as triggers that lead to its onset. The mechanisms postulated for this are either posttranslational modification of peptides, “molecular mimicry” activating T cells or “epitope spreading,” due to direct or T‐cell associated damage by the virus leading to autoreactive T cells. Bystander activation of T cells due to inflammatory cytokines released by the virus may also occur. Numerous studies in the literature have shown the onset of new RA or reactivation of arthritis in patients known to be in remission, post a viral infection. The COVID‐19 infection may lead to the same. As with other single‐strand RNA viruses like HIV, polymyositis, and fibromyalgia may also occur with the COVID‐19 infection. Viral arthritis, a self‐limiting polyarthritis, may also occur with SARS‐CoV‐2 infection. Chronic, widespread musculoskeletal pain as occurs post SARS syndrome is a possibility with COVID‐19.

Currently, patients on disease‐modifying antirheumatic drugs, biologics, or other immunosuppressive medications are required to consult their rheumatologist and stop these drugs during an infection. Noninfected patients are, however, advised to continue their medication during the epidemic. It is also noteworthy to mention that patients with rheumatic disease are more susceptible to the COVID‐19 virus either because of the rheumatologic disease itself or the medications used to treat their underlying disease.

From the current available data, no definite association can be established between COVID‐19 and rheumatological disorders, but further studies are needed to reaffirm the same.