The association of autonomous thyroid functional nodules with autoimmune thyroid disease
Chronic autoimmune thyroiditis and Graves disease (GD) are two forms of autoimmune thyroid disease (AITD).
The association of GD or other thyrotoxic forms of autoimmune thyroiditis with one or several toxic nodules is the Marine Lenhart syndrome (SML). It is a rare pathology with prevalence between 2.7 and 4.1%. Its physiopathology remains complicated and misunderstood, incriminating antithyroidian auto-antibodies such as TSH receptors antibodies and genetic alterations of the TSH receptors. The present study was accomplished afterwards, on the basis of the clinical records of the patients that were hospitalized in the Endocrinology Clinic in TgMures, between January 1999 and June 2004. In our study SML represented 1.42% (12 cases) of hyperthyroiditises, the majority of which were in females (91.67%). The highest incidence was in the age group 4060 years (average age being 49.5 years). In 58.33% of the cases the two diseases (the autoimmune and the autonomous one) were diagnosed simultaneously. The succesive form: GD followed by TTA thyroid toxic adenoma) 25%, whereas TTA followed by GD was present merely in 16.67% of the subjects under study. GD/Hashitoxicosis emerged after two, eight, and 10 years respectively after TTA was diagnosed. Exophtalmus was present in 25% (3) of patients. Compressive phenomena were detected in five patients (41.67%). After subtotal thyroidectomy for GD, in three patients (25%), recurrence of struma was detected after 17, 20 and 22 years respectively, and the struma eventually proved to be TTA. In one patient of male sex a microinvasive papillary thyroid carcinoma was also diagnosed, which recurred three years after subtotal thyroidectomy. Patients with autonomous thyroid nodules should be carefully evaluated with a view to a possible autoimmune predisposition, surgery being the most adequate therapy for SML, in order to prevent recurrences.