Bottom line: Out of all adult patients with a least 1 serum ferritin level >1,000μg/L from 2008-2010 (n=627), 153 had a malignancy, and 136 had iron-overload syndromes. Average ferritin level for the 6 patients with either adult-onset Still’s disease, systemic juvenile idiopathic arthritis, or hemophagocytic lyphohistiocytosis/macrophage activation syndrome was 14,242μg/L.
Source: Moore, Charles, MichelleOrmseth, and HowardFuchs. “Causes and significance of markedly elevated serum ferritin levels in an academic medical center.” Journal of clinical rheumatology 19.6 (2013):324-8.
The Bottom Line 