Table 3.

Similarities to and differences between the presentation of systemic juvenile idiopathic arthritis and inflammatory bowel disease in children

	Juvenile Idiopathic Arthritis	Inflammatory Bowel Disease
Onset of the disease	Acute onset with high, quotidian fevers,	Typically subacute illness with fatigue, anemia, and weight loss. Occasionally more fulminant presentation.
Gastrointestinal symptoms	Frequently abdominal pain, also nausea and anorexia	Loose stools and/or bloody diarrhea, abdominal pain, tenesmus
Muskuloskeletal symptoms	Initially, mild oligoarticular arthritis, frequently severe polyarthritis over the course of the disease	Nonerosive, asymmetric arthritis, affecting the large joints, parallel to intestinal involvement
Skin manifestations	Initial presentation with evanescent, salmon-colored, cutaneous eruption	Erythema nodosum, pyoderma gangrenosum
Laboratory abnormalities	Anemia, reactive thrombocytosis, markedly elevated erythrocyte sedimentation rate and C-reactive protein. Significantly elevated ferritin. Typically negative antinuclear antibodies and rheumatoid factor.	Anemia, elevated erythrocyte sedimentation rate and C-reactive protein, depressed albumin level, occult blood in the stool, elevated fecal calprotectin. Ferritin typically low or normal. Typically negative antinuclear antibodies and rheumatoid factor.