In minimal change disease, albumin is first to appear in urine because:
Minimal change disease (Nephrotic syndrome) =Albumin is the first among plasma protein to appear in urine because of: Size of the substance Glomerular filtration layer is thick but porous Any substance <= 4 nm diameter freely filters through this layer. Charge of the substance The sialoproteins like albumin are negatively charged This filtration of a substance like albumin which has diameter of 7 nm is negligible. Albumin has the smallest molecular weight and size out of all the plasma proteins Effacement of foot processes of podocytes leads to loss of recognizable intervening slit diaphragms as well as loss of negative charge of filtration layer The albumin stas appearing in urine as a result of these changes
Albumin has high affinity to glomerular basement membrane
Albumin has lower molecular weight compared to globulins
High albumin:globulin ratio in plasma
Active excretion of albumin
Nephrotic Syndrome