Zonder antistoffen mogelijk milder ziektebeeld hypothyreoïdie

Ondanks de hoge gevoeligheid van de huidige tests voor anti-TPO en anti-Tg, zijn bij sommige patiënten met hypothyreoïdie geen antistoffen tegen de schildklier aantoonbaar. Deze toestand - wel hypothyreoïdie maar geen antistoffen - wordt gewoonlijk aangeduid als seronegatieve autoimmuun thyreoïditis (= seronegatief-CAT).

Serum negative autoimmune thyroiditis displays a milder clinical picture compared with classic Hashimoto's thyroiditis
M Rotondi, L de Martinis, F Coperchini, P Pignatti, B Pirali, S Ghilotti, R Fonte, F Magri, L Chiovato

Met deze studie werd onderzocht of er een verschil is tussen patiënten zonder aantoonbare antistoffen of patiënten met klassieke autoimmuun thyreoïditis (CAT). De onderzoeksresultaten suggereren een milder ziekteverloop bij patiënten zonder antistoffen dan bij patiënten met antistoffen.


Despite high sensitivity of current assays for autoantibodies to thyroperoxidase (TPO) and to thyroglobulin (Tg), some hypothyroid patients still present with negative tests for circulating anti-thyroid Ab. These patients usually referred to as having seronegative autoimmune thyroiditis (seronegative CAT) have not been characterized and definite proof that their clinical phenotype is similar to that of patients with classic chronic autoimmune thyroiditis (CAT) is lacking.


To compare the clinical phenotype of seronegative-CAT and CAT as diagnosed according to a raised serum level of TSH with negative and positive tests for anti-thyroid Ab, respectively.


A case-control retrospective study enrolling 55 patients with seronegative-CAT and 110 patients with CAT was performed. Serum FT3, FT4, TSH, Tg-Ab, TPO-Ab were measured in all patients.


Patients with seronegative-CAT displayed significantly lower mean levels of TSH, higher mean FT4 levels and similar FT3 levels as compared to patients with CAT. Mean thyroid volume, was significantly greater in patients with CAT as compared with seronegative-CAT. Logistic regression demonstrated that FT4 and thyroid volume were significantly and independently related to the diagnosis (CAT / seronegative-CAT). Patients with seronegative-CAT had similar prevalence of thyroid nodules and of female gender but lower prevalence of overt hypothyroidism as opposed to patients with CAT.


These results suggest an autoimmune aetiology of seronegative-CAT, which however seems to have a milder clinical course as compared to CAT.

Lees ook