Haptoglobin study in myasthenia gravis.

OBJECTIVE A cross-sectional study of haptoglobin (Hp) in myasthenia gravis (MG) was designed, with the objective to identify its values and correlate them with different disease status. METHOD 46 patients were enrolled in the study, all having disease severity established according to the quantitative myasthenia gravis strength scores (QMGSS). Based on the functional scale determined by Myasthenia Gravis Foundation of America (MGFA) recommendations, patients were classified as having: complete stable remission (CSR; n=10); minimal manifestations-0 (MM0; n=6), minimal manifestations-1 (MM1; n=4); pharmacological remission (PR; n=6). Two other groups participated: thymomatous patients (T; n=10) and patients without imunosuppression or thymectomy, until the assessment for Hp (WIT; n=10). Hp dosage was done by immunonephelometry, blindly to clinical data. Student's t-test, Anova test and linear regression were employed for statistical analyses. RESULTS Statistically significant differences occurred between CSR+MM0 x WIT groups (86.62 x 157.57, p<0.001) and PR+MM1 x WIT groups (73.93 x 157.57, p<0.001). Linear regression showed correlation between Hp levels and QMGSS (r=0.759, p<0.001). CONCLUSION Our results suggest that Hp may be useful in clinical practice as a disease severity marker in MG.