Ancillary Studies

Question 1

IF findings in Goodpasture Syndrome

Answer 1

Linear staining with IgG and anti-C3 along alveolar septal basement membrane

Question 2

IF findings in lung Antibody-mediated Rejection (AMR)

Answer 2

C4d deposition along vascular endothelium within capillaries of the alveolar septa

Question 3

Hans algorithm

Answer 3

Question 4

Answer 4

Twinning and is pathognomonic for Castleman disease

Question 5

diagnostic criteria for HLH

Answer 5

Pathologic mutation of PRF1, UNC13D, Munc18-2, Rab27-a, STX11, SH2D1A, or BIRC4

5 out of 8 criteria below:
–Fever 38.3°C
–Splenomegaly
–Cytopenias (at least 2 of 3 lineages in the peripheral blood)
Hemoglobin <9 g/dL
Platelets <100 x103/mL
Neutrophils <1 x 103/mL
–Hypertriglyceridemia (fasting, 265 mg/dL) and/or hypofibrinogenemia (≤150 gm/dL)
–Hemophagocytosis in bone marrow, spleen, lymph nodes, or liver
–Low/absent NK-cell activity
–Ferritin >500 ng/mL
–Elevated soluble CD25 (soluble IL-2 receptor alpha)