Adrenal Calcifications

General considerations

• Hemorrhage is the most common cause
• Generally, patients with non-traumatic adrenal hemorrhage are critically ill and have a coagulopathy
• Adrenal glands are proportionately larger in neonates than adults and prone to complications from hypoxia or hypotension
• Unilateral 80% of time and involves right side 85% of time
• Unilateral adrenal hemorrhage rarely produces clinical findings
  • In adults, it is frequently found incidentally in trauma
• Most (90%) of adrenal tissue must be destroyed for adrenal insufficiency
• Adrenal hemorrhage is prognostically important because it may signify severe stress or unsuspected coagulopathy

Causes

• Hemorrhage
  • Neonatal
• More common than in adults
• May be associated with
• Birth trauma
• Hypoxia
• Septicemia
• Syphilis
• Adult
• Septicemia
• Waterhouse-Friderichsen Syndrome
• Septicemia, as from meningococcemia
• Hemorrhagic necrosis of adrenals from
• Septic emboli, or
• Disseminated intravascular coagulopathy
• Blunt abdominal trauma
• Adrenal may be compressed between spine and liver
• May undergo acute increase in adrenal venous pressure
• Shearing of small vessels may occur with deceleration
• Systemic coagulopathy
• Hemorrhage typically resolves in 4-6 weeks
• Addison Disease
• Primary adrenal insufficiency
• Affects adrenal cortex
• Adrenals are small
• Calcification can occur in 25% over a chronic course

• Infection
  • TB
• Calcified granulomas in adrenal
• Histoplasmosis
• Calcified granulomas in adrenal
• Neoplasm
• Neuroblastoma
• Most common solid abdominal mass in infancy
• Almost always unilateral (90%)
• Stippled or coarse calcification is common (up to 70%)
• Pheochromocytoma
• Rare tumor of adrenal medulla
• May be bilateral (10%)
• About 10% calcify
• Adrenal cortical adenoma
• Unilateral
• Low attenuation (<10HU) on non-enhanced CT
• Calcification is rare
• Myelolipoma
• Unilateral
• Large, fat-containing adrenal
• About 20% calcify
• Wolman Disease
• Rare, autosomal-recessive metabolic disease leading to death in infancy
• Leads to abnormal collections of cholesterol esters and triglycerides in “foam cells”
• Diffuse punctate calcifications in adrenals which may be enlarged but maintain adreniform shape
• Hepatosplenomegaly

Imaging Findings

• CT is the study of choice in adults
  • Adrenal hemorrhage and hemorrhagic adrenal rumors may appear similar
• Follow-up in 4 weeks to resolution for hemorrhage; tumors will not resolve
• Acute hemorrhage is hyperdense
• Associated with inflammatory stranding
• Adrenal is usually enlarged
• Bronchogenic carcinoma metastatic to the adrenals is the most common cause of an enlarged and hemorrhagic enhancing adrenal malignancy
• Ultrasound (US) is the modality of choice in neonates
• Sensitive to enlargement
• Glands may be large and hyperechoic early and hyperechoic centrally later
• MRI may be useful is evaluating the stage of hemorrhage
• On conventional radiography, adrenal calcifications will usually be bilateral and amorphous
  • Located in the region of the adrenals, adjacent to the spine
• Calcification may be seen within weeks of the hemorrhage