27-year-old man • muscle weakness • fatigue • electrolyte abnormalities • Dx?

Any abnormal result is an indication to exclude a physiologic cause of hypercortisolism by repeating at least 1 of the previous studies. As with the initial testing, normal results may rule out Cushing syndrome, while abnormal results would be confirmatory. (Conflicting results require additional evaluation.)

Morbidity and mortality. Finding the etiology of Cushing syndrome can present a challenge but is also rewarding due to the reversible nature of most of the abnormalities. That said, Cushing syndrome can have a significant impact on morbidity and mortality.

Morbidity. The case patient developed compression fractures throughout his thoracic and lumbar spine, with a loss of 4 inches in height, attributed to the delay in curative treatment (FIGURE 2); these were identified about 2 months after his initial presentation to a health care facility. In addition to bone mineral density, cognitive function and quality of life can be impacted by untreated hypercortisolism and Cushing syndrome.²

Mortality. In the earliest studies^6,7 (from the 1930s-1950s), the average survival rate was about 4.6 years and the 5-year survival was just 50%—and yet, outcomes data from modern treatment modalities are scant. While there is limited data on outcomes in untreated disease, the Endocrine Society states that treatment of moderate-to-severe cases “clearly reduces mortality and morbidity” while early identification and treatment of mild cases “would reduce the risk of residual morbidity.”²

Our patient underwent video-assisted thoracoscopic surgery, during which a nodule in the anterior lingula was removed. In addition, lymph node dissection was performed. Two lymph nodes were positive for atypical well-differentiated carcinoid tumor. After surgical removal, the patient’s cortisol levels normalized and his diabetes resolved.

THE TAKEAWAY

In primary care, the frequency at which we evaluate and diagnose type 2 diabetes without secondary cause can lead to cognitive biases, such as anchoring bias, that impact patient care. In this case, the atypical secondary nature of the diabetes was missed at 3 outpatient appointments prior to presentation at the hospital ED. In an active patient who has a normal BMI and a healthy diet—but systemic symptoms—it is critical to consider secondary causes of diabetes, such as Cushing syndrome.

CORRESPONDENCE
Anna Murley Squibb, MD, 2145 North Fairfield Road, Suite 100, Beavercreek, OH 45385; Anna.Squibb@ketteringhealth.org