Adrenal cortical hyperplasia: diagnostic workup, subtypes, imaging features and mimics

Abstract

Adrenal cortical hyperplasia manifests radiologically as a non-malignant growth, or enlargement, of the adrenal glands, specifically the cortex, although the cortex cannot be definitively identified by conventional imaging. Controlled by the pituitary gland, the adrenal cortex drives critical processes, such as the production of cortisol, mineralocorticoid and sex hormones. Any disruption in the multiple enzymes and hormones involved in these pathways may cause serious or life-threatening symptoms, often associated with anatomical changes in the adrenal glands. Diagnosis and treatment of adrenal cortical hyperplasia requires a thorough clinical evaluation. As imaging has become more robust so has its role in the diagnosis and treatment of adrenal conditions. CT has been the primary modality for adrenal imaging owing to reproducibility, temporal and spatial resolution and broad access. MRI serves a complimentary role in adrenal imaging and can be used to further evaluate indeterminate CT findings or serve as an adjunct tool without the use of ionizing radiation. Ultrasound and fluoroscopy (genitography) are most commonly used in children and foetuses to evaluate congenital adrenal hyperplasia. This article will discuss the clinical presentation, laboratory workup and imaging features of adrenal cortical hyperplasia, both congenital and acquired.

Figure 1.

A 20-year-old female with recent weight gain, menstrual irregularity, headache, worsening acne and dry skin, as well as hypercortisolism, which suppresses with high-dose dexamethasone suppression test. Axial and coronal contrast-enhanced T₁ weighted images of a hypoenhancing microadenoma in the floor of the anterior pituitary gland (a and b) (arrows). Coronal contrast-enhanced CT image of the abdomen shows normal adrenal glands (arrows) (c).

Figure 2.

Cushing disease in a 13-year-old female with 3-month history of worsening acne, hirsutism, fatigue, headache and muscle weakness. Contrast-enhanced axial CT image (a) shows bilateral hypertrophied adrenal glands (arrows). Sagittal T₁ weighted image of the brain demonstrates a normal-appearing pituitary gland (arrow) (b).

Figure 3.

A 33-year-old female with severe Cushing syndrome. Axial contrast-enhanced CT images of the abdomen (a) show diffusely enlarged adrenal glands (white arrows) secondary to ectopic ACTH production in the setting of a metastatic neuroendocrine carcinoma of the pancreas (black arrow) (b).

Figure 4.

A 15-year-old girl with surgically proven primary pigmented nodular adrenal dysplasia in the context of Carney complex, treated with bilateral adrenalectomy. Axial contrast-enhanced CT image of the abdomen (a), coronal T₂ weighted image of the abdomen (b) and magnified coronal T₂ weighted image isolating the right adrenal gland (c) show normal-sized adrenal glands with multiple subtle small nodules (arrows).

Figure 5.

A 39-year-old male with surgically proven ACTH-independent macronodular adrenal hyperplasia. Axial contrast-enhanced CT demonstrating multiple large nodules replacing both adrenal glands, with retained adreniform shape (arrows).

Figure 6.

Newborn female infant with ambiguous genitalia. Coronal (a) and axial non-contrast CT (b) show ambiguously female genitalia with an enlarged clitoris (arrow).

Figure 7.

Images of a female infant born with ambiguous genitalia, who was thought to be male at birth. Subsequent ultrasound showed a uterus, vagina and ovaries, and no testicles. Enlarged cerebriform adrenal glands (arrows) were noted on ultrasound (a and b). Persistent urogenital sinus (arrow) seen on fluoroscopy (genitography) (c) owing to in utero androgen exposure.

Figure 8.

A 27-year-old male with classical congenital adrenal hyperplasia. Contrast-enhanced axial and coronal CT ( a and b) show a macronodular appearance of the adrenal glands (arrows). Colour Doppler ultrasound (c) shows an eccentrically located, ill-defined hypoechoic testicular mass with posterior shadowing (arrow), representing a testicular adrenal rest tumour.

Figure 9.

Axial and coronal contrast-enhanced CT images (a and b) show bilateral enlarged hypodense, nodular adrenal glands (white arrows) with a single calcification (black arrow) in a patient with neurofibromatosis Type 1. Coronal contrast-enhanced T₁ weighted image (c) in 15 min delayed phase demonstrates delayed enhancement of these nodules.

Figure 10.

A 64-year-old female with incidentally noted asymptomatic adrenal lipomatous metaplasia found on staging scan for oesophageal cancer. Axial contrast-enhanced CT demonstrates oval foci of macroscopic lipid occupying the limbs of both adrenal glands (arrows), while the overall adreniform shape is maintained.

Figure 11.

A 35-year-old male with non-Hodgkin’s lymphoma. Axial, contrast-enhanced CT (a and b) shows bilateral hypodense, heterogeneously enhancing adrenal masses (arrows). Axial positron emission tomography/CT (c) shows marked avidity of both adrenal glands (arrows).

Figure 12.

Axial contrast-enhanced CT showing “tram-track” appearance (white arrow), typical for adrenal haematoma with surrounding periadrenal fat stranding (black arrow).

Figure 13.

Axial and coronal contrast enhanced CT images (a and b) demonstrate bilateral enlarged adrenal glands (arrows) due to biopsy proven histoplasmosis infection. Coronal PET CT (c) shows FDG avidity of the infected and inflamed adrenal glands (arrows).