Alarcon-Segovia and Villareal listed criteria for the diagnosis of mixed connective tissue disease (MCTD). The authors are from the Instituto Nacional de la Nutricion Salvador Zubiran in Mexico.
Parameters:
(1) serologic findings
(1a) titer of anti-RNP
(2) clinical findings
(2a) edema of hands
(2b) synovitis
(2c) myositis
(2d) Raynaud's phenomenon
(2e) acrosclerosis
Clinical Parameter
Findings
Points
edema of the hands
absent
0
present
1
synovitis
absent
0
present
1
myositis
absent
0
present (based on laboratory and/or biopsy findings)
1
Raynaud's phenomenon
absent
0
present (2 or 3 color phase)
1
acrosclerosis
absent
0
present, with or without proximal scleroderma
1
total number of clinical findings present
= SUM(points for the 5 clinical findings)
Criteria for the diagnosis of MCTD - both of the following:
(1) titer of anti-RNP >= 1:1,600
(2) total number of clinical findings >= 3
The sensitivity of the different criteria (Table 3, page 34):
(1) Raynaud's phenomenon (100%)
(2) anti-RNP titer (100%)
(3) edema of hands (98%)
(4) synovitis (98%)
(5) acrosclerosis (88%)
(6) myositis (60%)
The specificity depends on the disease being considered in the differential diagnosis, ranging from 0 to 100% (Table 4, page 35).
To read more or access our algorithms and calculators, please log in or register.
