Lithium carbonate-induced giant goiter and subclinical hyperthyroidism in a patient with schizophrenia:A case report and review of literature

BACKGROUND Lithium carbonate is used to manage various mood disorders,but it can cause thyroid abnormalities,including goiter,hypothyroidism,and hyperthyroidism.In rare cases,it can lead to giant goiter and subclinical hyperthyroidism,which may require surgical intervention in severe cases.CASE SUMMARY This case represents a rare development of giant goiter and subclinical hyperthyroidism in a schizophrenia patient who was subjected to prolonged lithium carbonate treatment.The enlarged thyroid gland caused pressure on the airway and recurrent laryngeal nerve,which led to respiratory distress,hoarseness,and dysphagia.The immediate danger of suffocation required urgent surgical intervention.In this report,we describe the case of a 41-year-old Chinese woman.This sheds light on the etiology and challenges associated with managing a giant goiter.The patient underwent a subtotal thyroidectomy to relieve airway compression and facilitate airway expansion.Prior to the procedure,the patient was given iodine to prepare.Concurrently,changes were made to the psychiatric medication regimen.Following surgery,the patient's respiratory function and vocal cord functionality improved significantly,and her mental state remained stable.CONCLUSION It is essential to monitor thyroid function,test thyroid antibody levels,and perform thyroid ultrasounds consistently in all patients undergoing long-term lithium carbonate treatment.This vigilance helps prevent severe and potentially life-threatening thyroid enlargement.

MULTIVARIATE ANALYSIS OF RELATIONSHIPS BETWEEN IODINE BIOLOGICAL EXPOSURE AND SUBCLINICAL THYROID DYSFUNCTIONS

Objective To assess the relationships between iodine biological exposure and subclinical thyroid dysfunctions. Methods The cross-sectional survey was performed to obtain the epidemiologic data of population in three communities with different iodine biological exposure： mild iodine deficiency [median urinary iodine concentration （MUI） of 50-99 μg/L], more than adequate iodine intake （MUI of 200-299 μg/L）, and excessive iodine intake （MUI over 300 μg/L）. Univariate and multivariate analysis （logistic regression analysis） were used to analyze the risk factors of subclinical hypothyroidism and subclinical hyperthyroidism. Logistic regression analysis with sex and age controlled suggested that more than adequate iodine intake （OR = 3.172, P = 0.0004） and excessive iodine intake （OR = 6.391, P = 0.0001） increased the risk of subclinical hypothyroidism, while excessive iodine intake decreased the risk of subclinical hyperthyroidism （OR = 0.218, P= 0.0001）. Logistic regression analysis including interaction of iodine intake and antibodies [tryroid peroxidase antibody （TPOAb） and thyroglobulin antibody （TgAb）] suggested that excessive iodine intake was an independent risk factor of subclinical hypothyroidism （OR = 6.360, P= 0.0001）, but independent protect factor of subclinical hyperthyroidism （OR = 0.193, P= 0.0001）. More than adequate iodine intake and it＇s interaction with TgAb increased the risk of subclinical hypothyroidism independently, in addition, it decreased the risk of subclinical hyperthyroidism at the present of TPOAb. Conclusion Both excessive iodine intake and more than adequate iodine intake could increase risk of subclinical hypothyroidism, supplement of iodine should be controlled to ensure MUI within the safe range.

EFFECTS OF LEVOTHYROXINE ON BONE METABOLISM IN PATIENTS WITH DIFFERENTIATED THYROID CANCER AFTER OPERATION AND ^(131)I ABLATION

Objective To investigate the effects of substitutive and suppressive doses of levothyroxine on bone metabolism in patients with differentiated thyroid carcinoma after surgery and 131I ablation. Methods The patients, who had received levothyroxine(L-T4) for at least 3 years for treating their differentiated thyroid carcinoma after surgery and 131I therapy, were classified into substitutive group and suppressive group according to the levels of serum free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH). We compared the levels of FT3, FT4, TSH, serum parathyroid hormone (PTH), serum calcium (Ca), serum phosphate (P), serum alkaline phosphates (ALP) and Bone mineral density (BMD) to those of healthy volunteers well matched for sex, age, menopausal status, and body mass index (BMI). Results No significant differences were found in the bone density and biochemical parameters of bone metabolism of the subjects treated with substitutive or suppressive doses of L-T4 compared with the control subgroup. No significant differences were observed among the subgroups according to accumulative doses of 131I. No bone fracture was found in all the patients. Conclusion The substitutive and suppressive doses of L-T4 are safe and necessary for patients with differentiated thyroid carcinoma after surgery and 131I therapy. Such treatment for 3 years is not associated with increased risk of osteoporosis. Much longer term of follow up is still needed in patients receiving substitutive and suppressive doses of L-T4.