Secondary Hemophagocytic Lymphohistiocytosis: A Challenging Diagnosis in a Patient with Autoimmune Hepatitis

Table 1

HLH-2004 diagnostic guidelines[1].

Criteria
Fever	>38.5°C or more
Splenomegaly	Present
Cytopenias	2 cell lines
Hemoglobin	< 90 mmol/L
Thrombocytopenia	< 100 x 10^9/L
Neutropenia	< 1 x 10^9/L
Hyperferritinemia	> 1123.5 pmol/L
Hypertriglyceridemia(fasting) and/or hypofibrinogenemia	> 3 mmol/L and/or < 1.7 mmol/L
Hemophagocytosis	Pathologic evidence in the bone marrow, spleen, lymph nodes or liver
Soluble CD25 levels (alpha chain of the soluble interleukin 2 receptor)	Elevated
Natural-killer-cell activity	Low or absent
OR
Molecular Diagnosis consistent with HLH	Pathological mutations of PRF1, UNC13D, STXBP1, RAB27A, STX11, SH2D1A or XIAP