It is not clear whether the IgE system plays a role in the pathogenesis of Graves'
disease which is an autoimmune disorder. The low-affinity receptor of IgE, which is
known as CD23, is not simply a receptor, it has various functions related to immune
cells. There is no information about its levels in Graves' disease. For these reasons,
serum IgE and soluble CD23 levels were determined in 40 patients with thyroid disease,
free from allergic disorders and/or parasitic infestations. Patients were divided
into three groups: Group 1: Patients with Graves' disease (n = 15, age: 33.4 ± 9.3,
9 women/6 men). Group 2: Patients with non-toxic diffuse or multinodular goitre (n
= 15, age: 31.0 ± 12.7, 13 women/2 men). Group 3: Patients with toxic nodular goitre
(n = 10, age: 44.6 ± 14.2, 9 women/1 men). There was no age or sex difference between
the groups (p > 0.05). Serum IgE level was somewhat higher in group 1 as compared
with the other two groups, but the difference was not statistically significant, the
values showed great individual variations (Group 1: 99.60 ± 105.10, Group 2:47.89
± 53.42, Group 3: 46.48 ± 35.90 IU/ml, p > 0.05). Serum sCD23 was detectable in 7
of 15 patients in group 1 (46.7%), 1 of 15 patients in group 2 (6.7%) and 1 of 10
patients in group 3 (10.0%). Serum sCD23 detectability ratio was found higher in patients
with Graves' disease than in the other two groups (p < 0.02). Serum IgE levels were
compared in sCD23 detectable and undetectable Graves' patients. The values were similar
(sCD23 detectable group: 105.30 ± 135.90, sCD23 undetectable group: 94.70 ± 55.30
IU/ml, p > 0.05). These results suggest that increased detectability of sCD23 is associated
with Graves' thyrotoxicosis. An underlying state of autoimmune thyroid disease may
be a permissive factor for this phenomenon.
Key words
Graves' Disease - IgE - CD23 - IgE Receptor - Hyperthyroidism
