MANIC EPISODE PRECIPITATED BY WITHDRAWAL OF SUBSTITUTION HORMONOTHERAPY IN SEVERE HYPOTHYROIDISM. REPORT OF A CASE. Slim Khaldi MD, Charles Kornreich MD PHD C.H.U Brugmann. Psychiatrc Unit. Brussels. Belgium Measures of electrolyte levels and blood counts were within normal limits. A cranial computed tomography revealed no abnormalities. Treatment consisted of Zupenthixol at a range dose of 60 mg per day to control agitation, and hormonal substitution by L-thyroxine which was reintroduced progressively, reaching 150 µg per day after 3 days. This led to a dramatic reduction in manic symptoms within 5 days and Zupenthixol was stopped at the sixth day. The patient was discharged 10 days after her admission. One month later, she was euthymic with a treatment consisting only of 100 µg per day of L-thyroxine. BACKGROUND AND AIM: The notion that clinical features of abnormalities of the thyroid axis can include psychiatric manifestations has been known for long. In 1874, Gull, followed by Ord in 1878, included psychiatric symptoms such as cognitive dysfunctions, paranoid psychosis and mood changes in their description of myxedema. Currently, hypothyroidism is regarded as a cause of major depressive disorder, mixed affective states and paranoid psychosis (1, 2). Mania has been described in patients with subclinical hypothyroidism (3) and less frequently in patients with overt hypothyroidism (4). However, mania has never been reported in lithium-naive patients with hypothyroidism with no affective disorders antecedents. We report a woman, with no previous personal history, who presented a typical manic episode after abruptly stopping thyroid substitution hormonotherapy. ex2 DISCUSSION: Hypothyroidism is classically associated with depression (3,5). Mania has been previously reported in association with hypothyroidism. This association may have been coincidental since it concerned only patients with affective disorders antecedents and especially those taking lithium (4). Goodwin and Sachs (2004) consider that excess in monoamine, especially dopamine is a central mechanism that possibly underlies the psychopathology of mania. The paradoxical association of hypothyroidism and mania in our patient might be due to a sharp fall of circulating thyroid hormones leading to a rapid increase in dopamine tone with no time to adjust regulatory neurotransmitter systems in the brain. CASE REPORT: A 53-years-old woman was admitted to the emergency department for psychomotor agitation. She had no previous personal or family psychiatric history. Her medical history consisted of Hashimoto thyroiditis 13 years earlier. This was treated by total thyroidectomy and hormone replacement. Thyroid function had been normal with 100 g L-Thyroxine per day. Three weeks before admission the patient decided to stop taking her medication, after reading about alternative medicine, because she thought that her endocrinologic problem could be controlled by volition. The physical examination was normal, excepting a slight bradycardia with a heart rate at 55 per minute. Results of laboratory tests revealed elevated TSH level (387, 5 U/ml, normal range: 0,3-4 U/ml), low triodothyronine level (0.1 ng/dl, normal range: 0,8-2 ng/dl), and low free thyroxine (0,8 pg/ml, normal range 2,1-4 pg/ml). CONCLUSION: This report stresses the importance of compliance in thyroidectomized patients taking substitution therapy. Thyroid function should be systematically monitored in patients presenting with mania in order to exclude both hyper- and hypothyroidism. REFERENCES: 1. Heinrich TW, Graham G. Hypothyroidism presenting as psychosis: Myxedema madness revisited. J Clin Psychiatry. 2003; 5(6): 260-266. 2. Wilson and Jefferson. Thyroid disease, behaviour and psychopharmacology. Psychosomatics. 1985; 26(6): 481-92. 3. Bommer M, Naber D. Subclinical Hypothyroidism in recurrent mania. Biol Psychiatry. 1992; 31: 729-734. 4. Levitte SS. Coexistent hypomania and severe hypothyroidism. Psychosomatics 1993; 34 (1): 96-7. 5. Goodwin G, Gary S: Bipolar Disorder. Health Press Oxford, 2004, pp 23-24. 6. Crocker AD, Overstreet DH. Modification of the behavioural effects of haloperidol and of dopamine receptor regulation by altered thyroid status. Psychopharmacology. 1984; 82 (1): 102-6.