Vasculitis

The tests available to support the diagnosis of vasculitis are:

EliA^™ PR3^S (14-5536-01) / EliA MPO^S (14-5537-01)

EliA PR3S and EliA MPOS are diagnostically relevant tests with outstanding performance¹

Tests with directly coated wells:
	EliA PR3^S	EliA PR3	Assay 1
Sensitivity	79.0%	51.0%	69.0%
Specificity	98.0%	95.3%	76.3%
Positive predictive value (PPV)	96.3	87.9	94.5
Negative predictive value (NPV)	87.5	74.5	82.5
Positive likelihood ratio (LR+)	39.5	10.9	25.9
Negative likelihood ratio (LR-)	0.21	0.51	0.32

	EliA MPO^S	EliA MPO	Assay 1
Sensitivity	56.5%	35.9%	29.4%
Specificity	99.3%	99.3%	99.3%
Positive predictive value (PPV)	98.1	97.1	96.4
Negative predictive value (NPV)	78.8	71.6	9.6
Positive likelihood ratio (LR+)	84.8	53.8	44.0
Negative likelihood ratio (LR-)	0.44	0.64	0.71

Performance data of EliA PR3^S/MPO^S and of PR3/MPO tests with directly coated antigen (internal study - number of patients included: PR3^S - 100 GPA (glomerulonephritis with polyangitis, Wegener's granulomatosis) and 150 disease controls; MPO^S - 80 MPA (microscopic polyangitis), 12 NCGN (necrotising crescentric glomerulonephritis) and 150 disease controls).

Cut-off/measuring range

	Negative	Equivocal	Positive	Measuring range
EliA PR3^S	<2.0 GPL-U/ml	2.0-3.0 GPL-U/ml	>3.0 GPL-U/ml	0.2-≥177 U/ml
EliA MPO^S	<3.5 GPL-U/ml	3.5-5.0 GPL-U/ml	>5.0 GPL-U/ml	0.2-≥134 U/ml

Coating

EliA PR3^S - human PR3 protein
EliA MPO^S - human MPO protein

Dilution

EliA PR3^S - 1:100
EliA MPO^S - 1:50

Sample material

Serum, plasma (EDTA, citrate, heparin)

Cut-off/measuring range, coating, dilution and sample material have been taken from respective Phadia 250 DFUs. The data is intended as a guide and should be treated accordingly. If you have any questions or uncertainty please contact your local service team or Laboratory Sales Representative.

References

Thermo Fisher Scientific. Internal Study.