Objectives

-Understand the pathophysiology of amyloidosis.

-Recognize the manifestations of amyloidosis in abdominal imaging on radiographs, CT, MRI, US, and nuclear medicine imaging.

Background

Amyloidosis is a disease process with extracellular deposition of insoluble beta-pleated protein-mucopolysaccharide fibril sheets. The characteristic pathologic finding is apple-green birefringence on polarized light microscopy with Congo red staining. Amyloid deposition can be secondary (reactive) to a chronic inflammatory disease or primary (idiopathic) without a known preexisting condition.

Imaging findings OR Procedure findings

This disease is multifocal in nearly 80% of cases. Soft tissue involvement results in a high morbidity and mortality due to organ dysfunction.

Key abdominal imaging findings:

-Stomach and small bowel: Nodular or diffusely thickened folds with possible calcifications

-Colon: Decreased haustra with thickened transverse folds and luminal narrowing

-Retroperitoneum: Infiltrative soft tissue with possible calcifications

-Liver/Spleen: Organomegaly with decreased attenuation on CT imaging and increased signal on T2-weighted MRI

-Gallbladder: Diffuse wall thickening

-Genitourinary system: Renal enlargement acutely, resulting in chronic renal atrophy; nodular or diffuse mural thickening of the bladder

-Subcutaneous fat: Infiltrative soft tissue with possible calcifications

Conclusion

Given the risk of multi-organ failure, radiologists must be cognizant of protean manifestations of amyloidosis. The interpreting radiologist may be the first to suggest this diagnosis and facilitate prompt treatment.

Objectives

-Understand the pathophysiology of amyloidosis.

-Recognize the manifestations of amyloidosis in abdominal imaging on radiographs, CT, MRI, US, and nuclear medicine imaging.

Background

Amyloidosis is a disease process with extracellular deposition of insoluble beta-pleated protein-mucopolysaccharide fibril sheets. The characteristic pathologic finding is apple-green birefringence on polarized light microscopy with Congo red staining. Amyloid deposition can be secondary (reactive) to a chronic inflammatory disease or primary (idiopathic) without a known preexisting condition.

Imaging findings OR Procedure findings

This disease is multifocal in nearly 80% of cases. Soft tissue involvement results in a high morbidity and mortality due to organ dysfunction.

Key abdominal imaging findings:

-Stomach and small bowel: Nodular or diffusely thickened folds with possible calcifications

-Colon: Decreased haustra with thickened transverse folds and luminal narrowing

-Retroperitoneum: Infiltrative soft tissue with possible calcifications

-Liver/Spleen: Organomegaly with decreased attenuation on CT imaging and increased signal on T2-weighted MRI

-Gallbladder: Diffuse wall thickening

-Genitourinary system: Renal enlargement acutely, resulting in chronic renal atrophy; nodular or diffuse mural thickening of the bladder

-Subcutaneous fat: Infiltrative soft tissue with possible calcifications

Conclusion

Given the risk of multi-organ failure, radiologists must be cognizant of protean manifestations of amyloidosis. The interpreting radiologist may be the first to suggest this diagnosis and facilitate prompt treatment.