Renal involvement in a silicosis patient – case report and literature review

Abstract

A 43-year-old Chinese man with a silicosis history was admitted to our hospital due to bilateral lower extremity edema for 1 year, exacerbating with hematuria for 2 months. He started working as a coal miner 30 years ago, and was diagnosed as silicosis 3 months ago. Lab tests revealed hematuria 3+, proteinuria 3+, and a serum creatinine value 2.47 mg/dl on routine check. He was diagnosed with focal proliferative IgA nephropathy (IgAN) and acute tubulo-interstitial nephritis by renal biopsy. He was treated with corticosteroids and got a remission 4 months later. Immunohistochemical staining showed the deposition of macrophage receptor with collagenous structure (MARCO), nod-like receptor pyrin domain-containing-3 (NLRP3), Caspase-1, apoptosis-associated speck (ASC), interleukin (IL)-1β, and IL-18 in both glomerular and tubulo-interstitial areas. We proposed that the silicon exposure could be related to his kidney disease in the patient and NLRP3 mediated inflammation might be involved in its pathogenesis which needs further explorations.

Case Report: Silicosis and IgA nephropathy, an exceptional association

“…1 The most common silica nephropathy described in the literature were crescentic glomerulonephritis, proliferative glomerulonephritis and chronic interstitial nephritis. 3 IgA nephropathy had been rarely reported even though it is the most common type of glomerulonephritis worldwide. 10 Only a few similar cases were described in the literature.…”

“…In fact, NLRP3 are the key in the inflammatory process caused by silica: they are involved, in association with alveolar macrophages, in binding and eliminating crystalline silica particles, and thus leading to pulmonary fibrosis in recent studies. 3,14 The real mechanism and pathophysiology are still not fully elucidated and needs more study to further understand how silica leads to autoimmunity and glomerulonephritis. In our case, simultaneous kidney and pulmonary disease could suggest the hypothesis that Ig A nephropathy might be associated with silica exposure.…”

“…However, silicosis-IgA N is a rare association and very few cases have been reported in the literature. [2][3][4][5][6] The underlying pathophysiology remains to be elucidated.…”

Case Report: Silicosis and IgA nephropathy, an exceptional association

“…1 The most common silica nephropathy described in the literature were crescentic glomerulonephritis, proliferative glomerulonephritis and chronic interstitial nephritis. 3 IgA nephropathy has been rarely reported even though it is the most common type of glomerulonephritis worldwide. 10 Only a few similar cases were described in the literature.…”

Therapeutic regulation of the NLRP3 inflammasome in chronic inflammatory diseases

“…Inhalation of silica crystals causes inflammation of the alveolar space, and long-term exposure to silica can lead to silicosis, a fibrotic lung disease. In addition, deposition of macrophage receptors with collagenous structures (MARCO), NLRP3, caspase-1, ASC, IL-1β, and IL-18 was found in both glomerular and tubulointerstitial areas of patients with a history of silicosis (Chen et al 2019 ).…”