Myxedema Psychosis: Neuropsychiatric Manifestations and Rhabdomyolysis Unmasking Hypothyroidism

Abstract

Background. Hypothyroidism is a prevalent endocrine disorder, often presenting with a spectrum of symptoms reflecting a hypothyroid state. It is also generally linked to causing mood swings, psychomotor slowing, and fatigue; however, in rare instances, it may lead to or induce acute psychosis, a condition referred to as myxedema psychosis (MP). We report a case of myxedema psychosis and present a literature review discussing its presentation, diagnosis, management, and prognosis. Case Presentation. A 36-year-old lady presented with one-week history of persecutory and paranoid delusions, along with visual and auditory hallucinations. She had no prior history of psychiatric illnesses. She underwent total thyroidectomy three years before the current presentation due to papillary thyroid cancer. She was not on regular follow-up, nor any specific therapy. On examination, she was agitated and violent. There were no signs of myxedema, and the physical exam was unremarkable. The initial workup showed a mild elevation in serum creatinine. Additional investigations revealed a high thyroid-stimulating hormone (TSH) of 56.6 mIU/L, low free T4<0.5 pmol/L, elevated creatine kinase of 3601 U/L, and urine dipstick positive for blood, suggestive of myoglobinuria. MRI of the head was unremarkable. We diagnosed her as a case of myxedema psychosis and mild rhabdomyolysis. She was started on oral thyroxine 100 mcg/day, fluoxetine 20 mg daily, and as-needed haloperidol. She was closely followed and later transferred to the Psychiatry Hospital for further management. Within one week, her symptoms improved completely, and she was discharged off antipsychotics with additional scheduled follow-ups to monitor TFTs and observe for any recurrence. Discussion and Conclusion. Myxedema psychosis is a rare presentation of hypothyroidism—a common endocrine disorder. Scarce data are describing this entity; hence, there is currently a lack of awareness amongst clinicians regarding proper identification and management. Moreover, the atypical nature of presentations occasionally adds to a diagnostic dilemma. Thus, any patient with new-onset psychosis should be screened for hypothyroidism, and awareness of this entity must be emphasized amongst clinicians and guideline makers.

Acute psychosis unveiling diagnosis of hypothyroidism: A case report

“…This hypothyroidism facade (Myxedema Psychosis) frequently masquerades as the primary psychotic disorder, especially in patients with no prior history of hypothyroidism [ 4 , 5 ]. Besides that, other characterizing symptoms of hypothyroidism may be completely missing at the time of presentation, as in our case, and the patient presents with nothing but psychiatric complaints [ [6] , [7] , [8] ] [ [6] , [7] , [8] ] [ [6] , [7] , [8] ]. As a result, it is crucial to highlight that many people with psychiatric problems may also have endocrine dysfunction, and that the absence of typical hypothyroidism signs and symptoms does not rule out the diagnosis [ 9 , 10 ].…”

“…Some of them can return to their original state of good mental health with this therapy, but this is not always the case [ 12 ]. Short-term antipsychotic treatment, typically with risperidone and haloperidol, is critical for assisting treatment and promoting faster recovery [ 2 , 4 , 6 , 9 ]. Fortunately, our patient also reverted to her original health state with the thyroid hormone replacement therapy and the anti-psychotic medications.…”

Evaluation and Treatment of New-Onset Psychotic Symptoms in a Patient with Autism Spectrum Disorder and Multiple Autoimmune Disorders

“…As in Mr. R's case, hallucinations (both auditory and visual) have also been observed. 10 Physical symptoms of hypothyroidism, such as fatigue, constipation, cold intolerance, and dry skin, may or may not be present in patients with myxedema psychosis. 11,12 Additionally, and unlike the other neuropsychiatric manifestations of hypothyroidism described above, the degree of thyroid dysfunction does not appear to correlate with the presence or severity of psychosis.…”

“…11,12 Additionally, and unlike the other neuropsychiatric manifestations of hypothyroidism described above, the degree of thyroid dysfunction does not appear to correlate with the presence or severity of psychosis. 10 In most published case reports of myxedema psychosis, the psychiatric symptoms are a presenting feature of new rather than existing hypothyroidism. Both autoimmune hypothyroidism (Hashimoto's thyroiditis) or hypothyroidism resulting from treatment for Graves' disease can cause myxedema psychosis.…”

“…Myxedema psychosis resolves with correction of hypothyroidism, typically within weeks to months but sometimes as early as days following initiation of thyroid hormone replacement. 10,15 Short-term antipsychotics are used in conjunction with levothyroxine and can often be discontinued on followup. 12,16,17 That being said, few cases of myxedema psychosis have been treated with thyroid hormone replacement alone.…”