Misdiagnoses seen for women with fibromyalgia-like symptoms: Report
Cases of 3 Cushing's syndrome patients highlight diagnostic challenges
Women with Cushing’s syndrome may be misdiagnosed with fibromyalgia — a chronic condition characterized by widespread pain and mental distress — despite showing Cushing’s symptoms, a new case series report demonstrates.
The researchers say these misdiagnoses of fibromyalgia, occurring in a trio of Cushing’s syndrome patients across three countries, highlight the difficulties of diagnosing women who experience generalized symptoms.
But an overarching concern is that these misdiagnoses delay appropriate treatment for patients and prolong the time until they can get symptom relief.
“These cases underscore the challenges in differentiating Cushing’s syndrome from other conditions, particularly when presenting with nonspecific symptoms similar to fibromyalgia,” the researchers wrote.
The report, “Cushing’s Syndrome Masquerading as Fibromyalgia: A Case Series,” was published in the journal Cureus.
All 3 women received misdiagnoses of fibromyalgia
Cushing’s syndrome comprises a group of disorders characterized by the presence of excessive levels of cortisol, a stress hormone that’s produced by the adrenal glands. In many cases, it’s caused by a tumor in the brain’s pituitary gland, which produces high amounts of adrenocorticotropic hormone, or ACTH, a signaling molecule that promotes cortisol production.
In other cases, patients have tumors in the adrenal glands that directly increase cortisol production. When the source of the problem is the pituitary gland, the condition is known as Cushing’s disease. Prolonged exposure to cortisol-like steroid medications, or corticosteroids, also can lead to the onset of Cushing’s.
The nonspecific nature of Cushing’s symptoms and clinical signs often lead to delays in diagnosis, and misdiagnoses.
Here, a team of researchers described three cases of women with Cushing’s syndrome who were initially misdiagnosed with fibromyalgia, a chronic health condition that causes pain and tenderness throughout the body.
The first woman, a 38-year-old from Egypt with a history of fibromyalgia, initially consulted her gynecologist in January 2022, with a headache and body swelling, and then was referred to a cardiologist, who recommended her blood pressure be monitored daily. Four months later, after a further doctor visit for multiple symptoms including dental bleeding and weight gain, she was diagnosed with purpura simplex, a condition marked by easy bruising due to blood vessel fragility.
She visited multiple clinicians between September 2022 and March 2023 because her symptoms persisted. Complaints included body swelling, generalized joint stiffness, and pain.
In April 2023, after seeing an orthopedic surgeon due to pain in her back and right hip, she was referred to a rheumatologist because her symptoms were not entirely consistent with fibromyalgia.
Blood tests continued to show low potassium levels, which can be a first sign of Cushing’s, and she showed other typical disease features, including weight gain and purple stretch marks.
Initial blood tests showed her ACTH levels were low, but her cortisol levels were high. A CT scan of the abdomen revealed the presence of an adenoma, a benign tumor, on her right adrenal gland.
She underwent surgery to remove the adenoma, then started treatment with corticosteroids after surgery to treat adrenal insufficiency — a condition in which the adrenal glands fail to produce enough hormones.
Case series highlights need for ‘heightened clinical suspicion’ amid symptoms
The second woman, age 47, from Bangladesh, reported widespread muscle and joint pain, and fatigue — symptoms consistent with fibromyalgia. However, she went on to have six bone fractures in a single year.
After multiple consultations with several physicians, a deeper look at her medical history revealed a history of high blood pressure and type 2 diabetes. Despite lacking the more typical symptoms of Cushing’s, she had experienced weight gain, which raised the possibility of a hormonal disorder.
Blood tests confirmed she had high levels of cortisol, which failed to drop after an overnight dexamethasone suppression test. This test measures the levels of cortisol in the blood in the morning after patients take a tablet of dexamethasone, a corticosteroid that normally blocks its production.
A CT scan revealed the presence of an adenoma in the left adrenal gland, confirming the presence of Cushing’s. The tumor was removed by minimally invasive surgery. Due to adrenal insufficiency post-surgery, the patient was temporarily treated with hydrocortisone.
The third woman, a 35-year-old from the United Arab Emirates with a history of asthma, hypothyroidism — low levels of thyroid hormones — and other conditions, sought medical advice following a two-year history of pain in several joints, muscle weakness, severe fatigue, and swelling in the extremities.
She had a round face, a buildup of fat behind the shoulders, and general obesity on physical examination, all signs of Cushing’s.
Despite extensive examinations, the exact cause of her symptoms remained unclear. She was first diagnosed with fibromyalgia and medicated accordingly. However, symptoms persisted.
Further blood tests were conducted, which showed low levels of circulating cortisol and ACTH. A synacthen test, which measures blood cortisol levels before and after administration of lab-made ACTH, was performed to evaluate her pituitary and adrenal gland response. Test results were normal.
Because her clinical history included the administration of corticosteroids and taking into account her overall symptoms, she was diagnosed with iatrogenic, or treatment-related, Cushing’s syndrome.
[This case series highlights the need for] a high index of suspicion, combined with targeted radiological and biochemical testing, [which] is crucial for accurate diagnosis and effective management [of Cushing’s syndrome].
“Our patients saw different physicians from various specialties and had multiple hospital visits over two to three years,” the researchers wrote. “Despite a multitude of other symptoms and signs … the initial diagnosis of fibromyalgia was carried forward by multiple physicians without proper re-evaluation, resulting in only symptomatic treatment.”
Their cases show that “heightened clinical suspicion … [is] essential,” the researchers wrote.
Overall, this case series highlights the need for “a high index of suspicion, combined with targeted radiological and biochemical testing, [which] is crucial for accurate diagnosis and effective management,” the team concluded.
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