HLH Diagnosis

By William Aird

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening hyperinflammatory syndrome of intense immune activation associated with fever, hepatosplenomegaly, cytopenias, hyperferritinemia, and presence of activated macrophages in hemopoietic organs.

HLH in adults is usually initiated by external causative factors such as drugs and infections or in the context of certain underlying diseases including cancer or autoimmune disease.

Diagnosis of HLH relies on clinical scoring systems since there no single laboratory finding has the sensitivity and specificity to definitively detect HLH. There are two commonly employed scoring systems:

  • HLH-2004 criteria
  • HScore

A recent study showed that both HLH-2004 criteria and HScore “demonstrated excellent discriminatory power in identifying HLH” (Eur J Haematol. 2022;109:129).

I recently saw a patient with adult-onset Still’s disease who presented with an HLH-like picture. Indeed, her clinical scores were virtually diagnostic of HLH (see graphics). She was treated with high-dose pulse methylprednisone, 1 g/day for 3-5 days) with good response.