Monozygotic twins discordant for juvenile dermatomyositis: clinical, serological and gene expression studies

Table 1 JDM patient clinical and laboratory characteristics at the time of sample

	Reference Range	JDM Twin 1	JDM Twin 2	JDM Twin 3	JDM Twin 4	JDM Twin 5
Age at presentation		5.58	3.71	5.30	9.40	2.5
Sex		Male	Female	Male	Male	Female
Race		White	White	White	White	White
Duration of untreated disease (months)^a		1.87	3.94	17.02	2.4	7.5
MSA		MJ (NXP2)+^b	p155/140 (TIF1-γ)+^b	Negative^b	MJ (NXP2)+	p155/140 (TIF1-γ)+ & Mi-2 indeterminate
Age at assessment		9.30	7.31	13.63	9.85	5.69
Current medications^c		OS, MTX	IVIG	none	OS, MTX	None
DAS-T		2.5	7	0	9	0
DAS-S		0	1	0	5	0
DAS-M		2.5	6	0	4	0
CMAS		49	47	52	ND	50
ERL (#/mm) [non-JDM twin ERL]	≥ 7	6.17 [7.73]	7.05 [7.72]	7.04 [6.00]	7.42 [8.04]	6.24 [6.5]
ESR (mm/h)	0–20	11	135	4	ND	17
Neopterin (nmol/L)	< 10	5.7	8	6.1	6.6	6
vWF: Ag (%)	48-234^d	151	153	67	152	192
CK (IU/L)	29-268^e	93	377	87	ND	40
LDH (IU/L)	188-403^f	412	ND	275	286	321
AST (IU/L)	18–57	34	ND	25	26	33
Aldolase (U/L)	3.4–8.6	ND	3.9	6.4	9.1	4.1
Total T cells	1051–3031	2186	1629	1472	1668
T helper cells (CD3 + CD4+)	548–1720	1133	872	846	1115
T cytotoxic cells (CD3 + CD8+)	332–1307	992	692	583	466
B cells (CD19+)	203–1139	458	106	428	986
NK cells (CD16+/CD56+)	138–1027	461	237	205	244

^aduration of untreated disease refers to the period from the onset of symptoms to the initiation of medical therapy
^bMyositis Associated Antibody: Ro indeterminate
^cOS=oral steroid, MTX = methotrexate, IVIG = intravenous immunoglobulin
^dall patients are blood type A
^e reference range for CK by age: 6-9y; (age 6 m-5y = 81–279; 6-9y = 29–268;10-13y = 26–268)
^f reference range for LDH by age: 3-6y; (age 7-11y = 188–358, ≥ 12y = 14–355)

ISSN: 1546-0096