[The significance of Titin antibody in diagnosing myasthenia gravis with thymoma].
OBJECTIVE
To investigate the clinical significance of Titin antibody (Titin-ab) in diagnosing myasthenia gravis with thymoma (MGT).


METHODS
Titin-ab and acetylcholine receptor antibody (AChR-ab) in the sera of 73 MGT patients with different thymic pathological patterns and 58 MG patients without thymoma (NTMG) were detected by ELISA.


RESULTS
The positive rate of Titin-ab in MGT group was 76.7%, significantly higher than those of NTMG group, other neurologic diseases group and healthy control group (P < 0.01). The sensitivity of Titin-ab in diagnosis of MGT was significantly lower than that of CT scan or MR of thymus (P < 0.05), but the specificity of Titin-ab in diagnosis of MGT was significantly higher than that of CT scan or MR of thymus (P < 0.05). The positive rate of Titin-ab was mainly related to the thymic pathology and was the highest in the thymic epithelial thymoma (TET) subgroup (95.1%). There was no significant correlation between the positive rate of Titin-ab and the Masaoka's stage of thymoma (P > 0.05). The titer of Titin-ab was highly correlated to the titer of AChR-ab in MGT group (r = 0.496, P < 0.01), but not in MGH group (r = 0.385, P > 0.05).


CONCLUSIONS
Detection of Titin-ab is a rather sensitive, specific, handy method in diagnosis of MGT (especially TET). It may play an important role in the pathogenesis of MGT.
Chen
X
X
Department of Neurology, Huashan Hospital, Medical Center of Fudan University, Shanghai 200040, China.
Lü
C
C
Qiao
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000032:analysis*; D015415:Biomarkers / Q000032:analysis; D002648:Child; D064211:Connectin; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009124:Muscle Proteins / Q000276:immunology*; D009157:Myasthenia Gravis / Q000175:diagnosis / Q000209:etiology / Q000276:immunology*; D011494:Protein Kinases / Q000276:immunology*; D012698:Serologic Tests; D013945:Thymoma / Q000150:complications / Q000276:immunology*
D001323:Autoantibodies; D015415:Biomarkers; D064211:Connectin; D009124:Muscle Proteins; C577285:TTN protein, human; D011494:Protein Kinases