A 7‐year‐old previously healthy male initially presented with neck pain and myalgias. Subsequently he developed a constellation of fever, abdominal pain, and intermittent rash. He received doxycycline for presumed tick‐borne illness with no clinical improvement. On transfer to a tertiary‐care hospital, exam was notable for an acutely ill, febrile child with a diffuse erythematous macular rash including palms and soles as well as migratory arthralgias and small‐joint arthritis with significant tenderness to palpation along the C‐ and L‐spine. A thorough workup was undertaken to evaluate potential infectious, oncologic, or rheumatologic etiologies. Blood and urine cultures, HIV, as well as titers for brucellosis, EBV, toxoplasma, RMSF, erlichiosis, Bartonella, and parvovirus were negative. CSF cultures and enterovirus PCR were also negative. CT and MR imaging was unrevealing. A bone marrow aspirate and biopsies were unremarkable. Rheumatologic labs were notable for negative ANA, ANCA, extractable nuclear antigen, RF, and HLA‐B27; ASO, C3, and C4 were also normal. CRP and ferritin were significantly elevated at 24.17 and 2728, respectively. The patient acutely decompensated with progressive pericardial effusion and hemodynamic compromise. Because of his clinical status, empiric high‐dose corticosteroids were initiated for a systemic inflammatory process of unclear etiology. He subsequently defervesced and had significant improvement in pain, arthritis, and serositis. Although there was high suspicion of systemic juvenile idiopathic arthritis (JIA), he did not meet criteria for such a diagnosis. He was discharged on NSAIDs and close follow‐up. At follow‐up, his fever and symptoms had recurred. Because of his pattern of quotidian fevers for greater than 2 weeks' duration, evanescent rash, polyarthritis, and serositis, the diagnosis of systemic‐onset JIA was ultimately made. Repeat lab evaluation showed elevated inflammatory markers and rising ferritin. He was readmitted and initiated on disease‐specific therapy with anakinra, with clinical improvement.
Systemic‐onset JIA is a rare condition that can have variable clinical manifestations and may even lack the classic hallmarks of fever and arthritis at the time of initial presentation. Often, children are acutely ill, leading clinicians to consider more common etiologies such as infection or malignancy. Although specific diagnostic criteria have been established, only 30% of patients meet these criteria at presentation. Thorough workup is essential to exclude other processes prior to treatment with steroids or disease‐specific agents. Making the diagnosis of systemic‐onset JIA allows for safe and effective treatment with recombinant IL‐1β receptor antagonists.
When workup for other etiologies is unrevealing after comprehensive evaluation of children with fever and arthritis, hospitalists must maintain a high‐index of suspicion for systemic onset JIA, even when initially lacking the diagnostic criteria.
To cite this abstract:Melvin J, Livingston J, Stephany A. When Failure to Meet Diagnostic Criteria Is Not a Diagnostic Failure. Abstract published at Hospital Medicine 2013, May 16-19, National Harbor, Md. Abstract 279. Journal of Hospital Medicine. 2013; 8 (suppl 2). https://www.shmabstracts.com/abstract/when-failure-to-meet-diagnostic-criteria-is-not-a-diagnostic-failure/. Accessed November 18, 2019.