Endocrine Abstracts

Introduction: Schmidt’s syndrome also known as autoimmune polyglandular syndrome type 2 (APS type 2) is a rare endocrine disorder defined by the combined occurrence of Addison disease with autoimmune thyroid disease. The rarity of the condition and the atypical presentation of adrenal insufficiency and hypothyroidism often lead to misdiagnosis with life-threatening consequences for the patient. In this study we report an exhaustive monocentric analysis of 22 patients diagnosed with a Schmidt’s Syndrome.

Patients and methods: We carried out a retrospective study of all the patients diagnosed of a Schmidt syndrome or APS type 2 in the Department of Endocrinology and Diabetology of University Hospital Farhat Hached of Sousse, over a period from 1999 to 2013. Adrenal insufficiency was diagnosed with a basal cortisol level<40 ng/ml or peak <180 ng/ml after Synacthen. Autoimmune Hypothyroidism was diagnosed with a T4 <7 pg/ml and TSH >10 mUI/l associated with the positivity of anti-Peroxydase antibodies. We analyzed clinical and biological aspects of these patients with SPSS ver. 23.0 software.

Results: We reported 22 cases, with a mean age of 31.77±11.26 years old, with 36.3% between 20 and 39 years old (P=0.02) and a predominance for female sex with a sex ratio=0.22 (P<10⁻³). The mean age of discovery of Addison’s disease was 32.5±9.2 with extremes ranging from 12 to 58 years. According to the age of discovery compared to hypothyroidism, Addison disease was diagnosed significantly before the diagnosis of Hashimoto’s disease in 59% (P=0.03), concomitant in 27.2% and posterior in 13.6%. Clinical symptoms made of melanodermia and hypoglycaemia suggested the diagnosis in 47% of all patients. An acute adrenal insufficiency was triggered by the hormonal thyroxin substitution in one case. Other autoimmune diseases were found in 27.2%, as a celiac disease (8%), type 1 diabetes (8%), Biermer anemia (7%) and autoimmune ovaritis in 4.2%.

Conclusion: Schmidt’s Syndrome is more likely to be associated with the female sex and young age. In our study, Hashimoto’s hypothyroidism was the first autoimmune disease discovered. The presence of at least one component of the APS type 2 must lead to the autoimmune screening of the other diseases. This screening could avoid the triggering of an adrenal insufficiency in thyroid hormonal substitution.