Hyponatremia and Encephalopathy in a 55-Year-old Woman with Syndrome of Inappropriate Antidiuretic Hormone Secretion as an Isolated Presentation of SARS-CoV-2 Infection.

BACKGROUND During the coronavirus disease 2019 (COVID-19) pandemic of 2020, varied presentations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been reported. The present report is of a case of hyponatremia and encephalopathy due to the syndrome of inappropriate antidiuretic hormone secretion (SIADH) as the main presentation of SARS-CoV-2 infection in a 55-year-old woman. CASE REPORT A 55-year-old woman with type II diabetes mellitus presented with confusion and slurring of speech, with a temperature of 38.5°C, heart rate of 120 bpm, blood pressure of 159/81 mmHg, and oxygen saturation of 98% on room air. She did not have edema on examination. Laboratory testing showed a low sodium level of 116 mEq/L (reference range, 135-145 mEq/L) with urine osmolarity of 364 mOsm/kg, urinary sodium of 69 mEq/L, urinary potassium of 15.6 mEq/L, and serum osmolarity of 251 mOsm/kg. The patient had normal serum thyroid-stimulating hormone and cortisol levels. A chest X-ray should no pulmonary infiltrates nor did a lumbar puncture reveal signs of infection. A real-time SARS-CoV-2 polymerase chain reaction assay was positive for COVID-19. Brain imaging with computed tomography was negative for acute infarct, intracranial hemorrhage, and mass effect. Based on findings from laboratory testing and physical examination, a diagnosis of SIADH was made. The patient was treated with 3% hypertonic saline, followed by salt tablets and fluid restriction, with improvement in her clinical symptoms and serum sodium level. CONCLUSIONS The present report is of a rare but previously reported association with SARS-CoV-2 infection. Encephalopathy and hyponatremia associated with SIADH without pneumonia or other symptoms of infection should be an indication for testing for SARS-CoV-2 infection.

Neuroleptic malignant syndrome with thyroid disorder: An unusual case report.

RATIONALE: Neuroleptic malignant syndrome (NMS) is a life threatening neurologic emergency associated with neuroleptic or antipsychotic agent use. NMS is rarely related to thyroid disease. PATIENT CONCERNS: We report a case of NMS in a 66-year-old male with past medical history of paranoid schizophrenia on chlorpromazine, diabetes, hypertension and asthma, who presented with a humeral fracture after a fall. Patient developed hyperpyrexia, altered consciousness, autonomic instability, elevated serum creatine kinase (CK) without rigidity. DIAGNOSES: CT head and workup for infection were negative. Electroencephalogram (EEG) showed generalized slow wave activity. Ultrasound revealed a large goiter with nodules. INTERVENTIONS: Chlorpromazine was stopped due to concern of NMS. Patient was treated with cooling, fluid and electrolyte maintenance. OUTCOMES: Patient slowly improved and CK level normalized. Thyroid-stimulating hormone (TSH) level trended down from 10.2 mIU/L to 0.02 mIU/L. Patient was discharged with aripiprazole. LESSONS: Hypothyroidism predisposes patients to NMS by altering central dopaminergic systems. The typical symptoms may be masked by hypothyroidism. Thyroid dysfunction should be excluded in all patients with NMS. Discontinuing antipsychotic agents decreases TSH levels which maybe due to the negative feedback of dopaminergic activity. This is the first case report describing dramatic changes in TSH after discontinuing chlorpromazine in NMS.