Presentation
Middle age man with bilateral loin pain.
Patient Data
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Bilateral asymmetrical perirenal enhancing soft tissue thickening extending to the renal sinus and infiltrating the pelvicalyceal systems associated with moderate hydronephrosis. No retroperitoneal soft tissue thickening, fibrosis or adenopathy. The findings are in favor of Erdheim-Chester disease.
Case Discussion
Erdheim-Chester disease is non-Langerhans cell histiocytosis resulting in multiple organs xanthomatous infiltration, usually presents with bone pain, diabetes insipidus, exophthalmos, interstitial lung disease, and renal impairment.
The differential diagnosis of this pattern of renal involvement includes retroperitoneal fibrosis, lymphoma and extramedullary hematopoiesis.