Psychiatric Symptoms Related to Cushing’s Disease May Include Delusions, Case Report Suggests

Delusions — fixed beliefs that do not change even when confronted with refutable evidence — are among the mental manifestations that can be  primary symptoms of Cushing’s disease, a case report suggests.

The study, “Losing my mind: an uncommon presentation of Cushing’s disease,” was published in the American Journal of Medicine.

Cushing’s disease often causes psychiatric symptoms. The most common are cognitive impairment, irritability, anxiety, and depression. Psychotic disorders and delusions are less common, but also occur.

Researchers in Singapore presented the case of a 44-year-old Chinese woman who had delusions and other mental symptoms as a consequence of Cushing’s disease.

The woman had been diagnosed with hypothyroidism (deficit of thyroid hormone) for 10 years. She took replacement therapy to treat this condition. She had delusions, which caused low mood, poor sleep, and suicidal thoughts, for two years. The patient also had gained 20 kilograms (about 44 pounds) in the past few years.

The woman came to the hospital with high levels of blood glucose and was diagnosed with diabetes, for which she started treatment. At that time, she reported having anxiety and memory loss that persisted in spite of treatment with antidepressants and antipsychotics, so she was admitted for a more detailed evaluation.

Doctors performed different exams of the woman’s brain, as well as a drug screen and metabolic analyses, but found no results that could explain the mental symptoms.

Physical examination showed a round face with plethora (red dots caused by excessive blood) and obesity. The patient showed no skin damage, and blood pressure was normal.

The doctors suspected that Cushing’s disease might be related to diabetes and mental symptoms. Lab exams showed high cortisol levels and elevated adrenocorticotrophic hormone (ACTH) — a hormone produced by the pituitary gland, which regulates cortisol production.

Contrast-enhanced MRI showed a small tumor in the pituitary gland, which confirmed the diagnosis of Cushing’s disease.

“Our patient had a predominantly psychiatric presentation with delusions and anxiety, and subsequently developed diabetes mellitus secondary to [excess cortisol] before she was suspected of having Cushing’s syndrome,” the researchers said.

“She did not exhibit the features that best discriminate Cushing’s syndrome, such as violaceous abdominal striae [purplish lines on the stomach], proximal myopathy [muscle tissue problems], and easy bruising.”

The woman underwent surgery to remove the tumor. After five days, she had no detectable levels of cortisol and was discharged under orders for replacement therapy.

During the months following surgery, the patient lost 14 kilograms (30 pounds). Diabetes management improved considerably, allowing her to reduce the dose or stop the three diabetes medications she was taking initially, six months after surgery.

The results of her psychiatric examination also improved, and eventually she stopped taking medication for mental disorders. The woman started a new job after being unemployed for a long time and is coping well.

A second MRI showed that the tumor did not come back. The patient still takes hydrocortisone as replacement therapy for cortisol.

“This case highlights the importance of considering Cushing’s syndrome in an individual presenting with new psychiatric symptoms,” the investigators concluded.

They also noted that “patients in remission should be monitored for psychiatric symptoms as well as cognitive impairment during longitudinal follow-up” because some patients might not fully recover after surgery.