What is it:

• Calcified lymphadenopathy refers to the enlargement of lymph nodes in which there is the presence of calcification.
• The calcification can be recognized on imaging as areas of very dense  foci  within the lymph nodes.
• The causes of calcified lymphadenopathy are often
  • benign but
  • can sometimes be associated with
    • malignancy or
    • other diseases.

AKA:

• Calcified Lymph Nodes or Calcified Lymphadenopathy

Abbreviation:

• CL (Calcified Lymphadenopathy)

How does it appear on each relevant imaging modality:

Chest X-ray:

• Parts:
  • Lymph nodes with calcification appear as dense, white areas on X-ray.
• Size:
  • The size of calcified lymph nodes can vary but often appear as smaller, well-defined structures in the mediastinum or hilum.
• Shape:
  • Calcified nodes are typically round or oval, though the calcification may cause some nodes to have irregular borders.
• Position:
  • Commonly seen in the
    • mediastinum
    • hilar, and
    • supraclavicular regions.
• Character:
  • Calcified lymph nodes are typically
    • well-defined and may have a
    • central or
    • eggshell appearance.

CT Scan:

• Parts:
  • Lymph nodes appear as calcified  areas of
  • dystrophic calcium.
• Size:
  • Nodes can be of various sizes, but those with extensive calcification are typically easier to identify.
• Shape:
  • Calcified lymph nodes are
    • round or oval with
    • sharply defined borders.
• Position:
  • Commonly seen in mediastinal, hilar, and supraclavicular regions.
• Character:
  • Calcification in the lymph nodes may be:
    • Central calcification: Often seen in benign conditions such as
      • tuberculosis,
      • histoplasmosis, and
      • silicosis.
    • Eggshell calcification: A characteristic finding in sarcoidosis,
    • silicosis,
    • Psammomatous  calcification:  May be seen in
      • metastatic
        • papillary thyroid carcinoma
        • mucin secreting carcinomas

MRI:

• Not utilized to evaluate calcifications but :
  • On MRI, calcified lymph nodes typically appear as
    • areas of
      • hypo-intensity in
        • T1 and
        • T2-weighted images

PET-CT:

• Role:
  • PET-CT has limited utility in assessing calcified lymph nodes, as calcified nodes do not generally show increased glucose metabolism.

Differential diagnosis:

Infection:

• Tuberculosis (TB):
  • Character: Granulomatous disease that can cause central calcification in lymph nodes.
  • Imaging Findings: Mediastinal or hilar lymph nodes with central calcification, often in the setting of prior infection.
• Fungal infections (e.g., Histoplasmosis, Coccidioidomycosis):
  • Character: Granulomatous inflammation leading to calcified lymph nodes.
  • Imaging Findings: Calcified lymph nodes in the mediastinum or hilar region, often with a well-defined appearance.

Inflammation:

• Sarcoidosis:
  • Character: A granulomatous disease that often results in eggshell calcification of lymph nodes.
  • Imaging Findings: Hilar and mediastinal lymph nodes with eggshell calcification, a hallmark of sarcoidosis.

Neoplasm (Benign or Malignant):

• Lymphoma:
  • Character: Can result in calcified nodes due to necrosis or fibrotic changes.
  • Imaging Findings: Lymph nodes with central calcification, although more often non-calcified.
• Metastatic Disease:
  • Character: Lymph node calcification in metastatic disease is usually peripheral and associated with specific malignancies like papillary thyroid carcinoma.
  • Imaging Findings: Peripheral calcification in mediastinal or supraclavicular nodes, possibly from a primary tumor like thyroid carcinoma.

Metabolic:

• Amyloidosis:
  • Character: Rarely, amyloid deposition can cause calcification in lymph nodes.

Iatrogenic:

• Post-radiation changes:
  • Character: Radiation therapy to the chest or mediastinum can cause lymph node calcification due to fibrosis or necrosis.
  • Imaging Findings: Calcified lymph nodes following radiation, often seen in patients treated for lung cancer or lymphoma.

Recommendations:

• Not usually necessary but if malignant disease suspected .
  • Biopsy or fine needle aspiration (FNA) may be required if malignancy is suspected or the cause of calcification is unclear.

Laboratory testing:

• Blood tests to evaluate fo
  • infections (e.g., CBC, tuberculin skin test), autoimmune markers (for sarcoidosis), or cancer screening (e.g., thyroid function tests).