Answer for BIR CoW 20 Sep 2020
Erdheim Chester Disease
Findings
CT chest in arterial phase shows diffuse thickening of the aortic wall from the aortic root, ascending aorta, arch of aorta as well as the descending thoracic aorta. CT abdomen and pelvis in arterial phase shows diffuse thickening of the aortic wall. Mild perirenal soft tissue thickening is present bilaterally. CT abdomen and pelvis in bone window setting shows cortical thickening in the meta-diaphyseal region with coarse trabecular pattern in the proximal femora.
Discussion
Erdheim Chester Disease is a rare form of non Langerhans’ cell histiocytosis characterized by infiltration of lipid laden histiocytes with foamy or eosinophilic cytoplasm in various organs (1). It commonly presents as bone pain in 5th to 7th decade. Skeletal system is the most common organ system involved (2). Fairly symmetrical metadiaphyseal sclerosis and cortical thickening and uptake on bone scan are commonly seen in the femur, tibia and fibula followed by ulna, radius, humerus. The less common mixed lytic sclerotic manifestation can be differentiated from Langerhans cell histiocytosis by the presence of sharply defined lytic lesions in the skull in the latter. Periaortic soft tissue thickening that can occur anywhere from the aortic root to the bifurcation gives a ‘coated aorta’ appearance (3). Retroperitoenal fibrosis is a differential diagnosis for infraabdominal aortic involvement. ECD demonstrates circumferential periaortic soft tissue and the IVC is typically spared. Whereas in retroperitoneal fibrosis, the posterior aspect of the aorta is spared while the IVC is involved. Infiltration of perirenal fat and soft tissue thickening is another classic retroperitoneal manifestation giving the appearance of a ‘hairy kidney (4). Lymphoma, hematoma, lymphangiomyomatosis and retroperitoneal fibrosis are differential considerations.
References:
1.) Mazor, Roei D, Mirra Manevich-Mazor, and Yehuda Shoenfeld. Erdheim-Chester Disease: A Comprehensive Review of the Literature. Orphanet Journal of Rare Diseases 8 (2013): 137. PMC. Web. 19 Sept. 2017.
2.) Antunes, Célia, Bruno Graça, and Paulo Donato. Thoracic, Abdominal and Musculoskeletal Involvement in Erdheim-Chester Disease: CT, MR and PET Imaging Findings. Insights into Imaging 5.4 (2014): 473–482. PMC. Web. 19 Sept. 2017.
3.) Lodhi U, Sarmast U, Yaddanapudi K. Multisystem Radiologic Manifestations of Erdheim- Chester Disease. Case Rep Radiol.2016 (2016) http://dx.doi.org/10.1155/2016/2670495
4.) Dion E, Graef C, Haroche J, Renard-Penna R, Cluzei P, Wechsler B et al. Imaging of Thoracoabdominal Invovlement in Erdheim-Chester Diease. Am J Roentgenol 2004 Nov; 183 (5): 1253-60
Findings
CT chest in arterial phase shows diffuse thickening of the aortic wall from the aortic root, ascending aorta, arch of aorta as well as the descending thoracic aorta. CT abdomen and pelvis in arterial phase shows diffuse thickening of the aortic wall. Mild perirenal soft tissue thickening is present bilaterally. CT abdomen and pelvis in bone window setting shows cortical thickening in the meta-diaphyseal region with coarse trabecular pattern in the proximal femora.
Discussion
Erdheim Chester Disease is a rare form of non Langerhans’ cell histiocytosis characterized by infiltration of lipid laden histiocytes with foamy or eosinophilic cytoplasm in various organs (1). It commonly presents as bone pain in 5th to 7th decade. Skeletal system is the most common organ system involved (2). Fairly symmetrical metadiaphyseal sclerosis and cortical thickening and uptake on bone scan are commonly seen in the femur, tibia and fibula followed by ulna, radius, humerus. The less common mixed lytic sclerotic manifestation can be differentiated from Langerhans cell histiocytosis by the presence of sharply defined lytic lesions in the skull in the latter. Periaortic soft tissue thickening that can occur anywhere from the aortic root to the bifurcation gives a ‘coated aorta’ appearance (3). Retroperitoenal fibrosis is a differential diagnosis for infraabdominal aortic involvement. ECD demonstrates circumferential periaortic soft tissue and the IVC is typically spared. Whereas in retroperitoneal fibrosis, the posterior aspect of the aorta is spared while the IVC is involved. Infiltration of perirenal fat and soft tissue thickening is another classic retroperitoneal manifestation giving the appearance of a ‘hairy kidney (4). Lymphoma, hematoma, lymphangiomyomatosis and retroperitoneal fibrosis are differential considerations.
References:
1.) Mazor, Roei D, Mirra Manevich-Mazor, and Yehuda Shoenfeld. Erdheim-Chester Disease: A Comprehensive Review of the Literature. Orphanet Journal of Rare Diseases 8 (2013): 137. PMC. Web. 19 Sept. 2017.
2.) Antunes, Célia, Bruno Graça, and Paulo Donato. Thoracic, Abdominal and Musculoskeletal Involvement in Erdheim-Chester Disease: CT, MR and PET Imaging Findings. Insights into Imaging 5.4 (2014): 473–482. PMC. Web. 19 Sept. 2017.
3.) Lodhi U, Sarmast U, Yaddanapudi K. Multisystem Radiologic Manifestations of Erdheim- Chester Disease. Case Rep Radiol.2016 (2016) http://dx.doi.org/10.1155/2016/2670495
4.) Dion E, Graef C, Haroche J, Renard-Penna R, Cluzei P, Wechsler B et al. Imaging of Thoracoabdominal Invovlement in Erdheim-Chester Diease. Am J Roentgenol 2004 Nov; 183 (5): 1253-60
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!