INTRODUCTION: Adult Onset Still's Disease (AOSD) is a rare systemic inflammatory disorder of unknown etiology. It classically presents as fever or unknown origin (FUO) with a constellation of symptoms and signs. The diagnosis requires high index of suspicion after excluding other diseases. We are presenting a case of fulminant AOSD with pleuropericarditis and pulmonary capillaritis which is not common.
CASE PRESENTATION: A 60-year-old Japanese man was admitted with a 2 week history of fevers, sore throat, fatigue, myalgia, right knee arthralgia and a 10-pound weight loss. He had a fever of 104.5°F, heart rate of 130/min, respiratory rate of 32/min and blood pressure of 150/70 mmHg. Physical examination revealed pericardial friction rubs, bibasilar lung crackles and right knee tenderness without effusion. There was no hepatosplenomegaly. The white blood cell (WBC) count was 37 × 103 cells/mm3 (88% neutrophils and 7% bands). The hemoglobin, hematocrit and platelet counts were normal. Blood urea nitrogen, serum creatinine, urinalysis and liver function tests were normal. C-reactive protein (CRP) was 26.20 mg/dl (< 0.80 mg/dl) and erythrocyte sedimentation rate (ESR) was 65 mm/hr (0–10 mm). All infectious work up was negative. Antinuclear antibody (ANA) profiles, antineutrophilic cytoplasmic antibodies (ANCAs), rheumatoid factor (RF) and angiotensin converting enzyme (ACE) level were all normal. The serum ferritin level was above 8000 ng/ml (22–322 ng/ml). The first chest CT (fig 1A) showed an infiltration of the posterior segment of the right upper lobe. However, the repeated chest CT for clinical worsening showed an interval development of pericardial and bilateral pleural effusions (fig 1B). A thoracoscopic biopsy of right lung demonstrated focal capillaritis and hemosiderin-laden macrophages which suggested an alveolar hemorrhage.
DISCUSSIONS: After exclusion of infectious etiologies, common connective tissue diseases or vasculitides and malignancies, the diagnosis of an Adult Onset Still's Disease (AOSD) was the most likely especially with markedly elevated serum ferritin. AOSD is a rare systemic inflammatory disorder of unknown etiology and classically characterized by “quotidian or double-quotidian” fever, arthritis/arthralgia, and a salmon-pink evanescent rash. Estimated incidence of AOSD is 0.16 cases per 100,000 persons per year. The disease tends to affect younger people; the onset is between 16- 35 years of age. Manifestations include fever (94–100%), arthralgia or arthritis (64–100%), myalgia (56–84%), rash (51–94%), sore throat (35–92%), splenomegaly (14–65%), lymphadenopathy (32–74%), pleuritis (12–53%), and pericarditis (10–37%). Laboratory study usually reveals marked leukocytosis. A serum ferritin level above 1000 ng/ml has been used to suggest AOSD, although a reduction of its glycosylated fraction (<20%) is more specific. Treatments include NSAIDs, steroids, disease modifying antirheumatic drugs (DMARDs) such as methotrexate, intravenous immunoglobulin, anti-tumor necrotic factor agents (eg infliximab or etanercept), anakinra (IL-1 receptor inhibitor) and rituximab (CD20- antibody).Our patient met three major (fever, arthralgia and leukocytosis) and two minor (sore throat, negative ANA and RF) diagnostic criteria. He had a fulminant course with pleuropericarditis which required a pericardiocentesis and a focal pulmonary capillaritis. After trials of multiple agents, ultimately, his disease was in remission with a combination of high dose prednisone and subcutaneous anakinra.
CONCLUSION: The AOSD is a very rare cause of FUO that should be considered as a diagnosis of exclusion in patients for whom extensive evaluation has ruled out infections, common autoimmune diseases or vasculitides and malignancy. Pulmonary capillaritis is a rare presentation. Treatments include multiple immunomodulating agents.
DISCLOSURE: Atikun Limsukon, No Financial Disclosure Information; No Product/Research Disclosure Information