Immune-mediated thrombotic thrombocytopenic purpura in patients with and without systemic lupus erythematosus: a retrospective study

Table 1 Baseline characteristics of patients with immune-mediated thrombotic thrombocytopenic purpura.

	Primary iTTP (n = 18)^a	SLE-TTP (n = 10)^a	p values
Demographic data
Age, yr	48.6 ± 10.8	32.6 ± 16.9	0.02
Female, n	7 (38.9)	10 (100.0)	< 0.01
New-onset TTP, n	18 (100.0)	10 (100.0)	1.00
Comorbidities	1 (5.6)	0 (0.0)	1.0
Haematological abnormalities
Platelet count, × 10⁹/L	17.4 ± 14.4	14.7 ± 12.5	0.62
Haemoglobin, g/L	83.5 ± 23.3	78.8 ± 16.6	0.58
Lactate dehydrogenase, U/L	2015.5 ± 2016.9	1272.4 ± 652.1	0.27
Severe ADAMTS13 deficiency	18 (100.0)	10 (100.0)	1.00
ADAMTS13 inhibitor	18 (100.0)	10 (100.0)	1.00
Immunological parameters
Complement C3 (g/L)	0.88 ± 0.24	0.76 ± 0.16	0.09
Complement C4 (g/L)	0.17 ± 0.07	0.12 ± 0.08	0.14
ANA	5 (27.8)	10 (100.0)	< 0.01
Low titre (< 1:320)	4 (22.2)	3 (30.0)	0.67
High titre (≥1:320)	1 (5.6)	7 (70.0)	< 0.01
Anti-dsDNA	0 (0.0)	4 (40.0)	0.01
Anti-SSA	4 (22.2)	7 (70.0)	0.02
Anti-SSB	0 (0.0)	2 (20.0)	0.12
Anti-U1RNP	0 (0.0)	2 (20.0)	0.12
Anti-Sm	0 (0.0)	1 (10.0)	0.36
APLs	1 (5.6)	1 (10.0)	1.00
SLEDAI	–	20.5 ± 7.7	–

Abbreviations: ANA anti-nuclear antibody, APLs anti-phospholipid antibodies, CNS central nervous system, dsDNA double-stranded DNA, iTTP immune-mediated TTP, SLE systemic lupus erythematosus, SLEDAI SLE disease activity index, SLE-TTP SLE-associated TTP, TTP thrombotic thrombocytopenic purpura
^a Values are expressed as the means ± SDs or the medians (interquartile ranges). Attributes values are expressed as numbers (percentages).

ISSN: 1750-1172