Accuracy of anti-ribosomal P protein antibody testing for the diagnosis of neuropsychiatric systemic lupus erythematosus: an international meta-analysis.
OBJECTIVE
To quantitatively evaluate the diagnostic accuracy of antibodies to ribosomal P proteins (anti-P) for neuropsychiatric systemic lupus erythematosus (NPSLE) in general, for psychosis, mood disorder, or both, and for other diffuse manifestations.


METHODS
This international meta-analysis combined standardized data from 1,537 lupus patients contributed by 14 research teams. Weighted estimation of sensitivity and specificity with fixed-effects and random-effects models, as well as summary receiver operating characteristic (SROC) curve analysis, was used to summarize test performance. The robustness of the overall estimates was examined in sensitivity analyses that included additional studies published up to November 1, 2004 in the Medline, EMBase, and Cochrane databases.


RESULTS
Combining the data from the 14 teams, the weighted sensitivity and specificity estimates for the diagnosis of NPSLE were 26% (95% confidence interval [95% CI] 15-42%) and 80% (95% CI 74-85%), respectively. For psychosis, mood disorder, or both, the sensitivity and specificity were 27% (95% CI 14-47%) and 80% (95% CI 74-85%), respectively. For other diffuse manifestations, the sensitivity was 24% (95% CI 12-42%), and the specificity was 80% (95% CI 73-85%). The proportion of patients with anti-P antibodies did not vary markedly across different presentations of NPSLE. Between-study heterogeneity was substantial, but the SROC curves were consistent with the weighted estimates. In further analyses that included another 24 published studies, only the sensitivity for psychosis and/or mood disorder was slightly improved, but it was still suboptimal (42% [95% CI 30-53%]); the specificity remained essentially the same (81% [95% CI 76-85%]).


CONCLUSIONS
Anti-P antibody testing has limited diagnostic value for NPSLE, and it is not helpful in differentiating among various disease phenotypes.
Karassa
Fotini B
FB
Dept. of Hygiene and Epidemiology, University of Ioannina School of Medicine, 45110 Ioannina, Greece.
Afeltra
Antonella
A
Ambrozic
Ales
A
Chang
Deh-Ming
DM
De Keyser
Filip
F
Doria
Andrea
A
Galeazzi
Mauro
M
Hirohata
Shunsei
S
Hoffman
Ilse E A
IE
Inanc
Murat
M
Massardo
Loreto
L
Mathieu
Alessandro
A
Mok
Chi Chiu
CC
Morozzi
Gabriella
G
Sanna
Giovanni
G
Spindler
Alberto J
AJ
Tzioufas
Athanasios G
AG
Yoshio
Taku
T
Ioannidis
John P A
JP
D000906:Antibodies / Q000097:blood*; D006801:Humans; D020945:Lupus Vasculitis, Central Nervous System / Q000097:blood* / Q000175:diagnosis*; D015203:Reproducibility of Results; D012269:Ribosomal Proteins / Q000276:immunology*; D012680:Sensitivity and Specificity
D000906:Antibodies; D012269:Ribosomal Proteins