Macrophage Activation Syndrome

Question 1

MAS is caused by excessive activation & expansion of what cells

Answer 1

Macrophages and T cells (predominantly CD8+)

Question 2

Pathognomonic feature of MAS

Answer 2

Pathological hemophagocytosis

Question 3

T/F Pathological hemophagocytosis is sensitive for overall diagnosis of MAS

Answer 3

F

Question 4

T/F Pathological hemophagocytosis is specific for MAS

Answer 4

F

Question 5

Rheumatic disease where MAS is seen most commonly

Answer 5

sJIA

Question 6

Other common rheumatic diseases associated with MAS other than sJIA

Answer 6

SLE and KD

Question 7

T/F MAS occurring at initial presentation of a rheumatic disease is not uncommon

Answer 7

T

Question 8

MC trigger of MAS in patients with rheumatic disease

Answer 8

Viral illnesses, particularly EBV and other members of the herpes family

Question 9

Drugs most commonly implicated as triggers for MAS in patients with rheumatic disease

Answer 9

Gold, MTX, sulfasalazine

Question 10

Cells with deficient function in MAS

Answer 10

NK cell
Cytotoxic T cell

Question 11

Cytokines implicated in MAS pathophysiology

Answer 11

IFN-γ and IL-18

Question 12

Cytokine implicated in MAS which is a well-known macrophage activator

Answer 12

IFN-γ

Question 13

Anti-IFN-γ monoclonal antibody approved in the US (2018) for treatment of pediatric HLH

Answer 13

Emapalumab

Question 14

T/F MAS is often associated with a flare of underlying sJIA rather than infection

Answer 14

T

Question 15

IL-18 is known for its ability to

Answer 15

Amplify lymphocyte production of IFN-γ

Question 16

Patients with sJIA and high levels of this cytokine more often have systemic manifestations rather than arthritis, and are also more likely to develop MAS

Answer 16

IL-18

Question 17

There is high expression of this scavenger receptor in hemophagocytic macrophages in MAS

Answer 17

CD163

Question 18

Receptor expressed by hemophagocytic macrophages in MAS whose best known function is related to its ability to bind hemoglobin-haptoglobin complexes and initiate pathways important for adaptation to oxidative stress induced by free heme and iron

Answer 18

CD163

Question 19

Receptor expressed by hemophagocytic macrophages in MAS associated with hyperferritinemia

Answer 19

CD163

Question 20

Decrease in this cell count is usually an early finding in MAS

Answer 20

Platelet

Question 21

T/F Cytopenias in MAS is due to decreased production

Answer 21

F, increased destruction peripherally

Question 22

T/F Liver involvement is not common in MAS

Answer 22

F, common

Question 23

T/F Significant hepatomegaly is frequently present in MAS

Answer 23

T