<prompt> Mercury affects which part of the kidney -PCTDCTCollecting ductLoop of Henle  <response>: Ans. a PCTRef: Robbins 9thpg 928; 8thpg 938Nephrotoxic AKICaused by Gentamicin, radiographic contrast agents, heavy metals eg mercury, organic solvents eg CCl4 .Extensive necrosis along mainly proximal convoluted tubule PCT ascending limb of Henles loop.On histologic examination, non-specific tubular necrosis, with some distinctive features:Mercuric chlorideSeverly injured cells contain large acidophilic inclusions, become totally necrotic, may undergo calcification.Carbon tetrachlorideAccumulation of neutral lipids fatty change, followed by necrosis.Ethylene glycolMarked ballooning hydropic or vacuolar degeneration of proximal convoluted tubules. Ca oxalate crystals are often found in the tubular lumens in such poisoning. 