- This case series reports on 13 patients who had a rheumatic disease and PCR-confirmed COVID-19 and subsequently underwent SARS-CoV-2 antibody testing on at least one occasion
- Three patients had negative or variable SARS-CoV-2 antibodies; two of these patients had required ICU admission for treatment of COVID-19
- Ten patients (77%), including six using immunosuppressive medications, had detectable antibodies
- Eight of those 10 patients fully recovered, one had persistent fatigue and one with systemic lupus erythematosus (without prior hematologic involvement) had recurrent episodes of thrombotic thrombocytopenic purpura
How rheumatic diseases and immunosuppressive medications affect the SARS-CoV-2 antibody response after COVID-19 is unknown. Disease-modifying antirheumatic drugs(DMARDs) generally blunt the immune response to pathogens, but the immunosuppressive medications dexamethasone and baricitinib are used in the treatment of hospitalized COVID-19 patients. In this case series, the majority of patients (10, 77%) developed SARS-CoV-2 antibodies, which is reassuring. Further studies are needed to investigate the effects of specific rheumatic diseases and DMARDs on the efficacy and durability of the antibody response to SARS-CoV-2.
In a letter to the editor of Annals of the Rheumatic Diseases, Massachusetts General Hospital's Kristin M. D'Silva, MD, fellow in the Division of Rheumatology, Allergy and Immunology, and physician Zachary S. Wallace, MD, MSc, of the Division of Rheumatology, Allergy and Immunology, report reassuring data about this issue, but its generalizability may be limited.
The researchers identified 188 patients at the Mass General Brigham health system who had a rheumatic disease and PCR-confirmed COVID-19 (not all were hospitalized). Subsequent antibody testing was performed on 13 of these patients.
The median time between PCR testing and antibody testing was 91 days.
Antibodies were undetectable in two patients:
- One patient had psoriatic arthritis treated with leflunomide and prednisone and had an uncomplicated COVID-19 course
- The other patient had antineutrophil cytoplasmic antibody-associated vasculitis treated with rituximab, azathioprine and prednisone; she was hospitalized for COVID-19 and required ICU admission
Antibodies were detectable in 10 patients (77%):
- Six were using immunosuppressive medications (prednisone, methotrexate, azathioprine, etanercept, rituximab, belimumab)
- Eight patients fully recovered, one had persistent fatigue and one with systemic lupus erythematosus (without prior hematologic involvement) had recurrent episodes of thrombotic thrombocytopenic purpura
One patient with antiphospholipid syndrome treated with prednisone, cyclophosphamide, rituximab and eculizumab required ICU admission for COVID-19. Subsequently, he initially had detectable antibodies (28–87 days after infection). However, starting on day 107 he had a negative antibody response. PCR testing was persistently positive and there was a clinical concern for recurrent COVID-19. He died on day 154 from respiratory failure.
Caveats About Interpreting the Findings
The antibody tests reviewed were obtained as part of routine clinical care at a tertiary care center. Antibody titers and tests for neutralizing antibodies were not available to the researchers, and the timing of antibody testing relative to SARS-CoV-2 infection was variable.
Refer a patient to the Rheumatology Unit