Histiocytic disorders

Question 1

LCH

Name high risk organs

Name CNS risk lesions

Answer 1

High risk organs: liver, bone marrow, spleen
-mortality 10%

CNS risk lesions: front of face, skull base and pituitary
- Single agent/no treatment has 40% risk. 20% if treated with systemic therapy

Question 2

Clinical manifestations that are suggestive of LCH

Answer 2

• vertebral plana
• floating teeth
• otitis externa with purulent drainage
• interstitial pattern with cysts and nodules with spontaneous pneumothorax
• diabetes insipidus
• hypoalbuminemia

Question 3

Immunophenotype

• LCH
• ECD
• RDD

Answer 3

LCH: CD1a+ CD 207+ birbeck granules

ECD: CD 68+ CD163+ CD1a-

RDD: Emperipolesis, S100+ fascin+ CD68++ CD14+ CD163+ CD1a/207-

Question 4

HLH Diagnostic criteria

Answer 4

5 out of 8
- fever
- splenomegaly
- cytopenias (2 lines)
- hypertriglyceridemias and/or hypofibrinogenemia
- hemophagocytosis
- ferritin > 500
- Elevated IL-2 R > 2400
-Decreased NK cell activity 
OR 
Gene mutation

Question 5

Major genetic mutations in HLH and associated syndromes

Answer 5

Perforin
Munc 13.4
Syntaxin 11 (STX11)
Syntaxin binding protein 2 (STXBP2)

LYST - Chediak Higashi
Rab27a - Griscelli
AP3B1 - Hermansky Pudlak2

XLP1 - SAP
XLP2 - BIRC4