HLH

Question 1

Test characteristics of hemophagocytosis for HLH diagnosis

Answer 1

Not pathognomonic or specific for HLH. A review of 78 bone marrow aspirates that showed hemophagocytosis included 40 that were associated with diagnosis of HLH and 38 without an associated diagnosis of HLH;

Question 2

HLH clinical course

Answer 2

The natural history of untreated HLH syndrome is almost uniformly fatal.

Question 3

Lab features

Answer 3

Very high ferritin (median 2950) (high sensitivity + specificity) + anemia (92%) + thrombocytopenia (over 80%, median 69k) + elevated liver enzymes (3x) and bilirubin (nearly all) + Hypertriglyceridemia or hypofibrinogenemia (90%) + LDH/GGT elevated + coag abnormalities + renal dysfunction + hemophagocytosis on BMB aspirate (25-100%)

Question 4

Signs/symptoms

Answer 4

Persistent fever (95%) + splenomegaly (89%) + dyspnea (unknown) + severe hypotension + possibly rash + highly variable neurologic abnormalities (30%) + pulmonary involvement (40%)

Question 5

Diagnosis

Answer 5

• No single clinical or laboratory feature has sensitivity and specificity to unequivocally diagnose HLH in adults.
• 1 scoring system is available
• Basically treat if clinical suspicion is high enough because mortality is so high.

Question 6

Treatment in general

Answer 6

HLH-94 protocol

Question 7

What does HLH-94 protocol consist of?

Answer 7

IF triggered by infection or rheumatologic condition –> treat trigger (eliminate stimulus)
Etoposide, dexamethasone
IF CNS disease –> intrathecal MTX and hydrocortisone
IF no improvement –> continue therapy as bridge to HCT

Question 8

Triggers for HLH

Answer 8

Infection
Rheumatologic conditions
Lymphoid malignancies

Question 9

treatment of EBV if associated with HLH

Answer 9

rituximab

Question 10

What are you looking for in bone marrow biopsy of suspected HLH patient?

Answer 10

hemophagocytosis