Endocrine Abstracts

Introduction: Immunologic background often present different association of two or more autoimmune diseases. However the coexistence of Basedow disease (BD) – the prototype of these disorders - with pernicious anemia (PA), sometimes as a component of pancytopenia, is rarely described. Between 50 patients operated on immunologic hyperthyroidism in a 20 years period only one case related this uncommon combination.

Case report: AB, a 46-year-old woman with a long standing BD treated from 1 year with antithyroid drugs (propylthiouracil) and β-blockers (propranolol) recorded a notable clinical improvement but with stationary or even increase size of her diffuse goiter. In addition she charged in the last three months palled skin, giddiness, tiredness, anorexia and coldness of the extremities. Laboratory workup showed TSH=4.6 mU/l, fT₄=38 pmol/l, fT₃=9 pmol/l, TRAB=1.8=1.8 UI/l. Current thyroid scan and US objectifies a diffuse 8×6 cm homogeneous, hypervascularised gland with uniform uptake. Though full blood count indicate pancytopenia with normochromic, normocytic anemia (Hb=9 g/dl, MCV=88 fL, MHCH=34 q/l). Also total white count was 3400 μ/l, platelet count was 48 000 μ/l and reticulocyte count was 1%. Peripheral smears show oval macrocytes, hypersegmented granulocytes and anisopoikilocitosis so a diagnosis of megaloblastic anemia secondary to Vitamin B12 deficiency was established. The standard treatment with intramuscular cyanocobalamin obtained substantial resolution of woman’s symptomatology. However maintained thyroidomegaly prompted our patient to undergo surgery. An adjusted near total thyroidectomy (Dunhill technique) was practiced followed by a smooth postoperative course. Histological examination of the operative piece (150 g) showed all stygma of thyrotoxicosis. Astoningshly endocrine equilibration was obtained together with positive hematological response occuring gradually within few months and maintaining further.

Discussions and conclusion: 1–3% of patients with immunogenic hyperthyroidism (BD) have associated hematological disorders as single-cell lineage abnormalities like pernicious anemia and related troubles or pancytopenias. In all cases BD precedes the blood disease. Causes of these pathologic coincidences reside unlikely as pure coincidence but rather from reciprocal influence, immune-mediate effects, outcomes of antithyroid therapy or vitamin B12 deficiency. Appropriate surveillance of all cases of untreated or treated BD is mandatory, recommended for early detection of pernicious anemia as for other autoimmune disorder.