3. Discussion
Cushing’s syndrome is a serious and well-known medical condition that results from persistent exposure of the body to excessive glucocorticoids, either from endogenous or, most frequently, exogenous sources [9]. The average age of diagnosis is 41.4 years, with a female-to-male ratio of 3:1 [10]. ACTH-dependent CS accounts for almost 80% of endogenous CS, while ACTH-independent CS accounts for nearly 20% [10]. This potentially fatal condition is accompanied by several comorbidities, including hypertension, diabetes, coagulopathy, cardiovascular disease, infections, and fractures [11]. Exogenous CS, also known as iatrogenic CS, is more prevalent than endogenous CS and is caused by the injection of supraphysiologic glucocorticoid dosages [12]. ACTH-independent CS is induced by uncontrolled cortisol release from an adrenal gland lesion, most often an adenoma, adrenocortical cancer, or, in rare cases, ACTH-independent macronodular adrenal hyperplasia or primary pigmented nodular adrenal disease [13].
The majority of data suggests that early diagnosis is critical for reducing morbidity and mortality. Detection is based on clinical suspicion initially, followed by biochemical confirmation [14]. The clinical manifestation of CS varies depending on the severity and duration of glucocorticoid excess [14]. Some individuals may manifest varying symptoms and signs because of a rhythmic change in cortisol secretion, resulting in cyclical CS [15]. The classical symptoms of CS include weight gain, hirsutism, striae, plethora, hypertension, ecchymosis, lethargy, monthly irregularities, diminished libido, and proximal myopathy [16]. Neurobehavioral presentations include anxiety, sadness, mood swings, and memory loss [17]. Less commonly presented features include headaches, acne, edema, abdominal pain, backache, recurrent infection, female baldness, dorsal fat pad, frank diabetes, electrocardiographic abnormalities suggestive of cardiac hypertrophy, osteoporotic fractures, and cardiovascular disease from accelerated atherosclerosis [10]. The current case presented with amenorrhea, weight gain, moon face, buffalo hump, and skin discoloration of the abdomen.
Similar to the current case, early diagnosis may be postponed due to the variety of clinical presentations and the referral of patients to different subspecialists based on their dominant symptoms (gynecological, dermatological, cardiovascular, psychiatric); it is, therefore, critical to consider the entire clinical presentation for correct diagnosis [18]. Weight gain may be less apparent in children, but there is frequently an arrest in growth with a fall in height percentile and a delay in puberty [19].
The diagnosis and confirmation of the etiology can be difficult and time-consuming, requiring a variety of laboratory testing and imaging studies [20]. According to endocrine society guidelines, the initial assessment of CS must include one or more of the three following tests: 24-hour UFC measurement; evaluation of the diurnal variation of cortisol secretion by assessing the midnight serum or salivary cortisol level; and a low-dose dexamethasone suppression test, typically the 1 mg overnight test [21]. Although UFC has sufficient sensitivity and specificity, it does not function well in milder cases of Cushing’s syndrome [22]. In CS patients, the typical circadian rhythm of cortisol secretion is disrupted, and a high late-night cortisol serum level is the earliest and most sensitive diagnostic indicator of the condition [23]. In the current case, the UFC was elevated, and cortisol was unsuppressed after administration of dexamethasone.
All patients with CS should have a high-resolution pituitary MRI with a gadolinium-based contrast agent to prove the existence or absence of a pituitary lesion and to identify the source of ACTH between pituitary adenomas and ectopic lesions [24]. Adrenal CT scan is the imaging modality of choice for preoperatively localizing and subtyping adrenocortical lesions in ACTH-independent Cushing’s syndrome [9]. MRI of the pituitary gland of the current case showed a microadenoma and a CT scan of the adrenals showed left adrenal adenoma.
Surgical resection of the origin of the ACTH or glucocorticoid excess (pituitary adenoma, nonpituitary tumor-secreting ACTH, or adrenal tumor) is still the first-line treatment of all forms of CS because it leaves normal adjacent structures and results in prompt remission and inevitable recovery of regular adrenal function [12], [25]. Laparoscopic (retroperitoneal or transperitoneal) adrenalectomy has become the gold standard technique for adrenal adenomas since it is associated with fewer postoperative morbidity, hospitalization, and expense when compared to open adrenalectomy [17]. In refractory cases, or when a patient is not a good candidate for surgery, cortisol-lowering medication may be employed [26]. The current case underwent left adrenalectomy.
Symptoms of CS, such as central obesity, muscular wasting or weakness, acne, hirsutism, and purple striae generally improve first and may subside gradually over a few months or even a year; nevertheless, these symptoms may remain in 10–30% of patients [27]. Glucocorticoid replacement is essential after adrenal-sparing curative surgery until the pituitary-adrenal function returns, which might take up to two years, especially if adrenal adenomas have been resected [25]. Chronic glucocorticoid excess causes lots of new co-morbidities, lowering the quality of life and increasing mortality. The most common causes of mortality in CS are cardiovascular disease and infections [28]. After one month of follow-up, serum cortisol was 36 nmol, and several features, such as weight loss (3 kg) and skin color, were resolved (pink striae became white).
In conclusion, the coexistence of adrenal adenoma and pituitary adenoma with CS is a rare possibility. Due to the diversity in the presentation of CS, an accurate clinical, physical and endocrine examination is always recommended. Laparoscopic adrenalectomy is the gold standard for treating adrenal adenoma.