Both Forms of Cushing’s, Exogenous and Endogenous, Found in Woman in Case Report
A rare case of a woman with both endogenous and exogenous Cushing’s syndrome, demonstrating that both forms of the disease can coexist, is described in a case report.
Juvenile idiopathic arthritis (JIA) is the most common type of arthritis in children. Without a known cause, it typically manifests as joint pain and inflammation in the hands, knees, ankles, elbows and/or wrists.
Corticosteroids are often prescribed to control inflammation and prevent further joint damage. However, chronic steroid therapy may predispose JIA patients to exogenous, or drug-related, Cushing’s syndrome.
In endogenous Cushing’s syndrome, there is an “internal” culprit — usually a benign tumor — that makes the body produce excessive amounts of the hormone cortisol. Among the health problems this can cause are type 2 diabetes and high blood pressure.
The co-occurrence of both forms of Cushing’s is uncommon.
Doctors at the Postgraduate Institute of Medical Education and Research in Chandigarh, India, treated a woman with JIA who had both forms of Cushing’s.
“She also had history of intermittent but painful swelling of multiple small and large joints since one year of age and history of stunted growth noticed at around four years of age,” the physicians wrote.
She developed normally during her first year of life, but her motor abilities regressed after an episode of high fever and arthritis in her right knee. She kept complaining of painful swelling in large and small joints, which resolved and reappeared with intermittent treatment.
She began using a wheelchair at age 5, and started on triamcinolone, a corticosteroid, to ease joint inflammation. Treatment lessened the inflammation, but did help with walking. She remained on triamcinolone for the past 16 years.
She weighed 16 kg (about 35 lbs.) when examined at the hospital, and had a height of 105 cm (about 3.5 feet), way under the target height (152 cm) for her age.
Her blood pressure was normal, and she had deformities typical of rheumatoid arthritis as well as some classic features of Cushing’s, including roundness of the face, facial redness (plethora), a fat hump on the upper back, and excessive body hair (hirsutism). She also had protruding eyes, poorly aligned teeth, and a recessed jaw.
Blood tests revealed small red blood cells due to lack of iron, and confirmed she did not have rheumatoid arthritis. A series of X-rays of her spine, legs and neck found signs of low bone density.
Lab tests showed excessively high cortisol levels, even after she stoped taking steroids for three days. In contrast, her levels of adrenocorticotropic hormone (ACTH) were under 1 pg/mL, far below the normal range of 5-60 pg/mL.
ACTH controls the production of cortisol. When the levels of cortisol in circulation are very high, the levels of ACTH drop, signaling the adrenal glands to stop producing cortisol. Corticosteroid therapy can also lower ACTH levels.
Further hormonal testing indicated she had ACTH-independent Cushing’s syndrome, a form of endogenous Cushing’s. This was confirmed with a contrast-enhanced computed tomography (CECT) of her adrenal glands, which found several nodules (tumors) in her left gland.
She was diagnosed with JIA and ACTH-independent Cushing’s syndrome complicated by exogenous Cushing’s. Physicians suggested her adrenal glands be removed, but the patient declined surgery due to multiple comorbidities.
This study highlights that although endogenous and exogenous Cushing’s in a person is rare, it should be considered in those whose Cushing’s syndrome-related symptoms fail to resolve after stopping corticosteroid therapy.