SARCOIDOSIS:
Sarcoidosis is a multisystem inflammatory disease characterized by the presence of non-caseating granulomas. Although sarcoidosis can virtually affect any organ in the body, the lung is the most common organ affected followed by the liver, skin, and eye.
Etiology:
Despite multiple investigations, the etiology was unclear. Currently, the most likely etiology is an infectious or noninfectious environmental agent that triggers an inflammatory response in a genetically susceptible host.
Renal Manifestations Of SARCOIDOSIS:
- CALCIUM DYSREGULATION
- HYPERCALCIURIA
- HYPERCALCEMIA
- OBSTRUCTIVE UROPATHY
- RETROPERITONEAL FIBROSIS & LYMPHADENOPATHY
- TUBULOINTERSTITIAL DISEASE
- GRANULOMATOUS INTERSTITIAL NEPHRITIS
- NON-GRANULOMATOUS INTERSTITIAL NEPHRITIS
- GLOMERULAR DISEASE(RARE) Pathophysiology
Clinically apparent renal involvement is considered rare, occurs in less than 5% of sarcoidosis patients, usually associated with granulomas in the kidney itself, and can lead to nephritis. However, hypercalcemia is the most likely cause of sarcoidosis-related renal disease. The cause for hypercalcemia is 1 -hydroxylation of 25(OH) vitamin D to form 1,25 (OH)2 vitamin D in the macrophages of sarcoid granulomas. Usually, treatment with corticosteroids shows a good response but relapses are frequent particularly while tapering steroids. Patients who are steroid intolerant/steroid-resistant are treated with cyclophosphamide, infliximab, azathioprine, and mycophenolate mofetil. Rarely sarcoidosis may lead to end-stage renal disease.
