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 Papillary necrosis/Interstitial nephriti  

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what is the difference between papillary necrosis, interstitial nephritis, and pyelonephritis in terms of microscopy and cells, (neutrophil, eosinophil)?

Edited by antidepressant on Mar 10, 2008 - 8:36 PM


I read few pages of renal part in Robbins, trying to summarize, I am still not clear on this,
  • Tubulointerstitial nephritis(TIN): refers to a group of inflammatory diseases of the kidneys that primarily involve the interstitium and tubules. The glomeruli may be spared, or affected later. Most cases TIN is caused by bacterial infection, the renal pelvis is predominantly involved, so its called pyelonephritis, pyelo is pelvis.(so pyelonephritis is same as TIN).
  • Interstitial nephritis is subgroup of TIN, when TIN is due to noninfectious origin, results from drugs(NSAIDS, penicillin, rifampin, cimetidine, phenindione), metabolic disorders (hypkalemia,), irradiation, immune reaction. we see fever, eosinophilia (may be transient), rash, leucocytouria including eosinophils. Morphologically, interstitium involved, there is pronounced edema, infiltration of mononuclear cells, mainly lymphocytes, and macrophages. Eosinophils and neutrophils may be present, often in large numbers. The glomerulii are normal except in those cases caused by NSAIDS when minimal change disease and the nephrotic syndrome develop concurrently.
  • Papillary necrosis or necrotizing papillitis is an infrequent form of acute pyelonephritis, (necrosis of papillae), which is common in diabetics who first develops acute pyelonephritis, which get complicated by significant UTI. Or it may be seen in chronic interstitial nephritis associated with analgesic use(NSAIDS).

So, papillary necrosis could be a complication of NSAID induced interstitial nephritis, right?


also, analgesic nephropathy is developement of chronic interstitial nephritis, often associated with renal papillary necrosis occuring in a person who consume large quantities of analgesics. Most patients develop this nephropathy consume mixtures containing combination of phenacetin, aspirin, acetaminophen, caffeine, and codeine for long periods. Aspirin and acetaminophen are the major culprits.


yes rt it seems.Thanks AD. smiling face


These are vast topics so i will try to explain your doubts in short;

Renal papillary necrosis:-Is the ischemic necrosis of the papilla in the medulla of the kidney.Analgesic nephropathy(chronic use of NSAID'S) is the most common cause.Phenacetin,aspirin,and acetaminophen are the usual culprits.Risk is greatly increased with combined use of aspirin and acetaminophen.S/S are acute colicky abdominal pain(due to acute ureteral obstruction from sloughed papillae),gross hematuria,and passage of tissue fragments in urine.

Acute Interstitial nephritis:-Is the inflammation affecting the interstitium of the kidney surrounding the tubules.Allergic reaction to the drugs is the most common cause.Pencillins,sulfonamides,NSAID'S,and diuretics are the usual culprits.Infections and immunologic diseases are the other causes.S/S are acute onset of oliguria,fever,rash,azotemia,and eosinophilia.Important urine analysis findings are hematuria,WBC casts,and pathognemonic eosinophiluria.

Acute pyelonephritis:-Is the life threatening bacterial infection of the kidney involving renal pelvis,tubules,and interstitium.Ascending infection is the most common cause and E.Coli is the most common pathogen involved.S/S are high grade fever with chills,malaise,nausea,vomiting,flank pain,lower urinary tract signs(like dysuria,frequency,and urgency).Urine analysis reveals pyuria and WBC cats.The presence of fever,costovertebral angle tenderness,and WBC casts in urine help in distinguishing pyelonephritis from cystitis.

Hope this helps you.


thanks KG, and pr20.

since, none of you disagreed my assumption, i will stick to it!

moral of the story;"everything could be everything"nod

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