Some causes of increased protein in the urine include functional proteinuria due to increased renal blood flow (exercise, fever, high-output heart failure), orthostatic proteinuria, primary glomerular disorders (focal segmental glomerulosclerosis, membranous nephropathy, minimal change disease, IgA nephropathy), secondary glomerular disorders (diabetic nephropathy, preeclampsia, postinfectious glomerulonephritis, HIV, hepatitis B and C, syphilis, lupus nephritis, amyloidosis, sarcoidosis, sickle cell disease, Alport’s syndrome ), Fanconi syndrome, heavy metal ingestion, acute tubular necrosis, tubulointerstitial nephritis, lymphoma, monoclonal gammopathy, multiple myeloma, myelodysplastic syndromes, hypertensive nephrosclerosis, ischemic renal disease/renal artery, and interstitial nephritis.

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