TABLE 2.

HSCT characteristics and C4d staining of kidney tissue

ID	Diagnosis	HSCT type	Conditioning regimen	Cause of death	Renal pathology findings	PTC C4d stain	Arteriolar C4d stain	Glomerular C4d stain	Tubular BM C4d stain
TA-TMA group
1	NB	Auto	MA	Alive at last follow-up	TMA	Rare	Diffuse	—	Focal
2	NB	Auto	MA	Alive at last follow-up	TMA	—	Diffuse	Diffuse	—
3	MB	Auto	MA	Alive at last follow-up	TMA	Rare	Focal	Rare	Rare
4	AMT	Allo	MA	Alive at last follow-up	TMA	—	Focal	—	—
5a	NB	Auto	MA	Relapsed NB	TMA	Rare	Diffuse	—	—
6	NB	Auto	MA	TA-TMA	TMA	—	—	Rare	—
7	HLH	Allo	RIC	TA-TMA	TMA	—	—	Focal	—
8	NB	Auto	MA	Alive at last follow-up	TMA	Rare	Diffuse	Focal	Focal
Control group
1	XLP	Allo	RIC	Necrotizing encephalopathy	GS/TA	—	—	Focal	—
2	FA	Allo	MA	ARDS/adenoviral infection	TN	—	—	Rare	—
3	HLH	Allo	RIC	Pulmonary hypertension	Normal	—	—	Focal	—
4	CID	Allo	RIC	Pseudomembranous colitis	↑ Vascular CT	—	—	Diffuse	—
5	WAS	Allo	RIC	ARDS	TA/IF	—	Focal	Diffuse	—
6	XLP	Allo	RIC	Adenoviral infection	GS/TA	—	—	Focal	—
7	HLH	Allo	RIC	Chronic GVHD	Abscesses	—	—	Focal	—
8	IPEX	Allo	RIC	Septic shock	Normal	—	—	Rare	—
9	HLH	Allo	RIC	Disseminated fungal infection	TN	—	—	Focal	—
10	HLH	Allo	MA	Adenoviral infection	TN	—	—	—	—
11	ALL	Allo	MA	Sepsis/relapsed leukemia	Normal	—	—	Rare	—
12	EWS	Auto	MA	ARDS/relapsed EWS	Infarcts	—	—	—	—

^aBoth biopsy and autopsy with similar findings.

Diffuse if >50% tissue staining, focal if 10% to 50% of tissue, rare if 1% to 10% of tissue, or negative (—) if 0%.

ALL, acute lymphoblastic leukemia; Allo, allogeneic HSCT; AMT, amegakaryocytic thrombocytopenia; ARDS, acute respiratory distress syndrome; Auto, autologous HSCT; BM, basement membrane; CID, combined immunodeficiency; CT, connective tissue; EWS, Ewing sarcoma; FA, Fanconi anemia; GS, glomerular sclerosis; GVHD, graft-versus-host disease; HLH, hemophagocytic lymphohistiocytosis; IF, interstitial fibrosis; IPEX, immunodysregulation polyendocrinopathy enteropathy X-linked syndrome; MA, myeloablative; MB, medulloblastoma; NB, neuroblastoma; PTC, peritubular capillary; RIC, reduced intensity conditioning; TA-TMA, transplant-associated thrombotic microangiopathy; TA, tubular atrophy; TN, tubular necrosis; WAS, Wiskott-Aldrich syndrome; XLP, X-linked lymphoproliferative disease.