Secondary Diabetes Mellitus in Patients with Endogenous Cushing’s Syndrome - Clinical Characteristics at Diagnosis

Abstract

Background and aims. Endogenous Cushing’s syndrome is a rare disease associated with severe morbidity and increased mortality if untreated. Diabetes mellitus is a frequent initial complaint of these patients. Our aim was to investigate the clinical characteristics at the time of diagnosis in a cohort of patients with endogenous Cushing’s syndrome (CS). Material and methods. A retrospective analysis of the presentation of 68 cases diagnosed with endogenous Cushing’s syndrome followed-up in our institution was performed. Results: There were 57 women and 11 men, aged 18-74 years (mean 45.57±14.2). 38 had Cushing’s disease (CD) while 30 had adrenal CS. The most frequent signs/symptoms leading to the initial consultation and diagnostic suspicion were central obesity (55 cases, 80.88%), purple striae (28 cases, 41.1%), secondary arterial hypertension (27 cases, 39.7%), secondary diabetes mellitus (24 cases, 35.29%), hirsutism in 23/55 women (41.81%), hypogonadism in 23 cases (33.82%), proximal myopathy in 17 cases (25%), edema (10 cases, 14.7%). 13 cases (19.11%) also had secondary osteoporosis (diagnosed by dual energy x-ray absorptiometry - DXA osteodensitometry). Among the two diagnostic groups there were several differences. Proximal myopathy, secondary hypertension and diabetes mellitus were all more frequent in cases with adrenal Cushing compared to those with CD. (p= 0.011, 0.006 and 0.024, respectively). This did not reflect more severe hypercortisolism in adrenal CS, as the hormonal values were similar in the two groups. Conclusion: If associated with certain clinical signs, some nonspecific (central obesity, edema, arterial hypertension), other more suggestive of CS (purple striae, proximal myopathy) diabetes mellitus could be the initial sign of this severe condition.