SERUM AUTOANTIBODIES AGAINST SULFATIDE AND PHOSPHOLIPID IN NIDDM PATIENTS WITH DIABETIC NEUROPATHY

OBJECTIVE - We investigated the presence of antisulfatide and antiphos pholipid antibodies and the relationship between these antibodies and the results of quantitative tests of nerve function in NIDDM patients with diabetic neuropathy. RESEARCH DESIGN AND METHODS - Antisulfatide and antiphospholipid antibodies were measured in serum samples obtaine d from 68 NIDDM patients with diabetic neuropathy by an enzyme-linked immunosorbent assay (ELISA). Each patient was classified into one of t hree groups based on the combined neuropathy score (determined by the symptom score, the results of autonomic nerve function tests, and the vibration perception test), as follows: mild in = 26), moderate in = 2 2), and severe (n = 20). Nerve conduction studies were performed in a subgroup of 37 patients. RESULTS - The antisulfatide antibody was dete cted in 1 (4%) of 26 patients in the mild group, 4 (18%) of 22 patient s in the moderate group, and 8 (40%) of 20 patients in the severe grou p (P < 0.01 vs. mild group). The antiphospholipid antibody was detecte d in none of the patients in the mild group, 8 (36%) of 22 patients in the moderate group (P < 0.001 vs. mild group), and 6 (30%) of 20 pati ents in the severe group (P < 0.01 vs. mild group). The threshold ampl itude, determined by the vibration perception test, was significantly higher in antibody-positive patients than in antibody-negative patient s: antisulfatide antibody, 55.9 +/- 46.8 mu m in = 13) vs. 22.9 +/- 13 .7 mu m (n = 55), P < 0.001; antiphospholipid antibody 47.2 +/- 32.5 m u m in = 14) vs. 24.5 +/- 23.2 mu m (n = 54), P < 0.01. The conduction velocity of the sural nerve was slower in the antisulfatide antibody- positive group (37.9 +/- 11.1 m/s, n = 12) than in the antisulfatide a ntibody-negative group (45.2 +/- 6.0 m/s, n = 19) (P < 0.05). CONCLUSI ONS - These results suggest that autoimmune nerve destruction may be i nvolved in diabetic neuropathy in NIDDM patients.