Case Report: Immune Response Against SARS-CoV-2 Potential Trigger for Adult-Onset Still Disease

Woman looking at thermometer
Ill woman looking at thermometer at home.
Authors of a case study reported severe adult-onset Still disease manifestations in a patient with long-term sequelae of COVID-19.

A misdirected immune response against SARS-CoV-2 may have led to the development of adult-onset Still disease (AOSD), according to findings from a case report published in Lancet Rheumatology. Authors of the case report described the occurrence of AOSD in a patient with long-term sequelae of COVID-19 for 6 months, with the first manifestation of AOSD after infection with SARS-CoV-2.

Systemic inflammation, fever, increased serum ferritin, and the potentially life-threatening cytokine release syndrome are common features of both COVID-19 and AOSD. Previous studies have shown that the cytokine interleukin (IL)-1 has a key role in the pathogenesis of AOSD and COVID-19, and it has been suggested that the same mechanisms may trigger AOSD and the severe immune over-reaction reported in some patients with COVID-19.

The patient was a 29-year-old White woman, with no notable medical history, who developed mild symptoms of COVID-19 and seemed to have recovered after 24 days, with no need for therapy or hospitalization. However, 4 days later, she developed fever, transient maculopapular rashes, arthralgia, headache, sore throat, and night sweats. Repeat oropharyngeal swab test was positive for SARS-CoV-2 and there was evidence for antibodies against nucleocapsid protein, but no evidence for IgM and IgG against Spike protein.

Six months after the diagnosis of COVID-19, the patient developed fever, sore throat, myalgia, arthralgia, and lymphadenopathy with elevated serum inflammatory markers, liver enzymes, NT-pro-BNP, and troponin T levels. Testing for SARS-CoV-2 was negative.

The patient was hospitalized, and during her admission developed salmon-colored rashes, hypotension, and tachycardia, followed by pericarditis, pleural and pericardial effusions, and pulmonary infiltrates. The positron emission tomography computed tomography (PET-CT) scan ruled out vasculitis, and bronchoscopy with bronchoalveolar lavage revealed acute bronchitis with nonpurulent secretion. Peripheral blood samples showed no evidence of viral or bacterial pathogens. The patient fulfilled the criteria for AOSD and treatment with high-dose prednisolone was introduced.

Because there was further clinical deterioration, with extension of pericardial effusion, hypotension, and vena cava congestion, treatment with anakinra was added with a significant improvement of clinical symptoms, and the patient was discharged 5 days later.

The use of an IL-1 antagonist has been very effective for AOSD and studies have suggested it may improve outcomes in patients with severe COVID-19.

“The case of this patient shows that long [COVID-19] can mimic AOSD and delay the time point of diagnosis. This finding is important, because the number of patients with long-term sequelae of COVID-19 is continuously rising and early treatment of AOSD might prevent complications and reduce mortality,” the authors of the case report concluded.


Bamidis AD, Koehler P, di Cristanziano V, et al. First manifestation of adult-onset Still’s disease after COVID-19. Lancet Rheumatol. Published online March 26, 2021. doi:10.1016/S2665-9913(21)00072-2