[Influence of hypergammaglobulinemia on antiphospholipid antibodies titres].
OBJECTIVE
Antiphospholipid antibodies (aPL), anticardiolipin antibodies (aCL) or lupus anticoagulant (LA), are indispensable for the diagnosis of antiphospholipid syndrome (APS). However, antiphospholipid assays can generate false positive results.


METHODS
We have studied the influence of hypergammaglobulinemia (HG) on aPL antibodies titers in 232 patients twice as positive for aPL antibodies.


RESULTS
Out of 232 patients, 93 have an APS (76 primary APS, 17 secondary APS). Thrombosis occurred 138 times in APS patients. Of 139 patients without APS, 95 have an auto-immune disease, 28 have an isolated prolonged KCT and 16 an evolutive neoplasia. LA seems to be the best marker of APS. On the other hand aCL IgG and M, anti-beta2-GP1 IgM titers are significantly higher in patients without APS but with HG.


CONCLUSIONS
Those results suggest that biological APS diagnosis should be carefully performed in patients with HG. In this case, other additional risk factors must be considered for the etiological diagnosis of thrombosis.
Lambert
M
M
Service de médecine interne, hôpital Huriez, CHRU de Lille et université de Lille II, France. m-lambert@chru-lille.fr
Fauchais
A-L
AL
Dubucquoi
S
S
Launay
D
D
Caron
C
C
Prin
L
L
Hachulla
E
E
Hatron
P-Y
PY
Devulder
B
B
D000328:Adult; D017152:Antibodies, Antiphospholipid / Q000097:blood*; D015415:Biomarkers / Q000032:analysis; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D006942:Hypergammaglobulinemia / Q000150:complications* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013927:Thrombosis
D017152:Antibodies, Antiphospholipid; D015415:Biomarkers