Difference between revisions of "Xanthogranulomatous pyelonephritis"

Xanthogranulomatous pyelonephritis
	Diagnosis in short
	; Xanthogranulomatous pyelonephritis. CD68 immunostain.
LM	abundant (foamy) macrophages (associated with the collecting system - medulla, not cortex), +/-giant cells, +/-cholesterol clefts, +/-interstitial lymphocytes and plasma cells, +/-interstitial fibrosis, +/-calcifications
LM DDx	malakoplakia, RCC - especially PRCC, granulomatous disease, chronic pyelonephritis, interstitial nephritis, occasionally renal cell carcinoma
Stains	PAS-D -ve
IHC	CD68 +ve, CD10 -ve, pankeratin -ve
Site	kidney - see kidney tumours
Associated Dx	diabetes mellitus, history of UTI, nephrolithiasis, GU obstruction (various causes)
Prevalence	uncommon
Radiology	dilated upper GU system
Clin. DDx	renal cell carcinoma, pyelonephritis
Treatment	antibiotics, occasionally nephrectomy

Latest revision as of 02:38, 22 February 2017

Xanthogranulomatous pyelonephritis, abbreviated XGP, is an inflammatory process of the kidney that can mimic renal cell carcinoma.

General

May mimic renal cell carcinoma - especially radiologically.
Usually lower pole.^{[citation needed]}
Associated with:
- Diabetes mellitus.
- History of urinary tract infection.^[1]
- Nephrolithiasis.
- GU obstruction.^[2]
Occasionally an indication for nephrectomy.^[1]^[2]
Most common organism (in the context of nephrectomy specimens) - Proteus mirabilis.^[2]

Microscopic

Features:

Abundant (foamy) macrophages.
- Associated with the collecting system - medulla, not cortex.
+/-Giant cells.
+/-Interstitial lymphocytes and plasma cells.
+/-Interstitial fibrosis.
+/-Cholesterol clefts (common).
+/-Calcifications - dystrophic.

DDx:

Malakoplakia.
- Basophilic inclusions -- inside or outside of macrophages - often size of RBC or larger (Michaelis-Gutmann bodies).
Renal cell carcinoma - especially papillary RCC (as this has foamy macrophages).
Granulomatous disease.
Chronic pyelonephritis.
Interstitial nephritis.
Renal cell carcinoma - foamy macrophages may be abundant.^[3]

Images

Xanthogranulomatous pyelonephritis - CD68 stain. (WC/Nephron)

www:

Several images of XGP (archivesofpathology.org).^[4]

Stains

PAS-D -ve.
- Done to look for malakoplakia.

IHC

CD68 +ve.
RCC markers (CD10, RCC) all negative.

Sign out

RIGHT KIDNEY, NEPHRECTOMY:
- XANTHOGRANULOMATOUS PYELONEPHRITIS.
- CHRONIC INTERSTITIAL NEPHRITIS.
- INCREASED NUMBERS OF TOTALLY SCLEROSED GLOMERULI AND GLOMERULI WITH FOCAL 
  SCLEROSIS.
- MARKED INTERSTITIAL FIBROSIS.
- NEGATIVE FOR MALIGNANCY.

COMMENT:
Immunostaining demonstrates abundant CD68 positive cells (macrophages).  A CD10 immunostain 
is non-concerning (it highlights glomeruli). A pankeratin immunostain is non-concerning 
(it highlights benign renal tubules).

Compatible XGP

"KIDNEY" LESION, LEFT, BIOPSY:
- FIBROMUSCULAR TISSUE WITH A MIXED INFLAMMATORY INFILTRATE.
- CELLULAR DEBRIS WITH SURROUNDING LOOSELY AGGREGATED HISTIOCYTES.
- NO RENAL PARENCHYMA IDENTIFIED.
- NEGATIVE FOR MALIGNANCY.

COMMENT:
A SMA immunostain highlights the muscle component, and a CD68 immunostain marks 
abundant histiocytes. No epithelial component is identified with a pankeratin 
immunostain.

Micro

The sections show degenerative renal parenchyma with surrounding histiocytes, other inflammatory cells, fibrosis and cholesterol clefts.

References

↑ ^1.0 ^1.1 Afgan F, Mumtaz S, Ather MH (2007). "Preoperative diagnosis of xanthogranulomatous pyelonephritis". Urol J 4 (3): 169–73. PMID 17987581.
↑ ^2.0 ^2.1 ^2.2 Al-Ghazo MA, Ghalayini IF, Matalka II, Al-Kaisi NS, Khader YS (October 2006). "Xanthogranulomatous pyelonephritis: Analysis of 18 cases". Asian J Surg 29 (4): 257–61. PMID 17098659.
↑ Iskandar, SS.; Prahlow, JA.; White, WL. (Jun 1993). "Lipid-laden foamy macrophages in renal cell carcinoma. Potential frozen section diagnostic pitfall.". Pathol Res Pract 189 (5): 549-52. doi:10.1016/S0344-0338(11)80364-X. PMID 8378177.
↑ Li, L.; Parwani, AV. (May 2011). "Xanthogranulomatous pyelonephritis.". Arch Pathol Lab Med 135 (5): 671-4. doi:10.1043/2009-0769-RSR.1. PMID 21526966.

[pmid17987581-1] 1.0 ^1.1 Afgan F, Mumtaz S, Ather MH (2007). "Preoperative diagnosis of xanthogranulomatous pyelonephritis". Urol J 4 (3): 169–73. PMID 17987581.

[pmid17098659-2] 2.0 ^2.1 ^2.2 Al-Ghazo MA, Ghalayini IF, Matalka II, Al-Kaisi NS, Khader YS (October 2006). "Xanthogranulomatous pyelonephritis: Analysis of 18 cases". Asian J Surg 29 (4): 257–61. PMID 17098659.

[pmid8378177-3] Iskandar, SS.; Prahlow, JA.; White, WL. (Jun 1993). "Lipid-laden foamy macrophages in renal cell carcinoma. Potential frozen section diagnostic pitfall.". Pathol Res Pract 189 (5): 549-52. doi:10.1016/S0344-0338(11)80364-X. PMID 8378177.

[pmid21526966-4] Li, L.; Parwani, AV. (May 2011). "Xanthogranulomatous pyelonephritis.". Arch Pathol Lab Med 135 (5): 671-4. doi:10.1043/2009-0769-RSR.1. PMID 21526966.

[1]

[2]

[3]

[4]

@@ Line 1: / Line 1: @@
-#redirect [[Kidney_tumours#Xanthogranulomatous_pyelonephritis]]
+{{ Infobox diagnosis
+| Name       = {{PAGENAME}}
+| Image      = Xanthogranulomatous_pyelonephritis_cd68.jpg
+| Width      =
+| Caption    = Xanthogranulomatous pyelonephritis. CD68 immunostain.
+| Synonyms   =
+| Micro      = abundant (foamy) macrophages (associated with the collecting system - medulla, not cortex), +/-giant cells, +/-cholesterol clefts, +/-interstitial lymphocytes and plasma cells, +/-interstitial fibrosis, +/-calcifications
+| Subtypes   =
+| LMDDx      = [[malakoplakia]], RCC - especially [[PRCC]], granulomatous disease, [[chronic pyelonephritis]], interstitial nephritis, occasionally [[renal cell carcinoma]]
+| Stains     = [[PAS-D]] -ve
+| IHC        = CD68 +ve, CD10 -ve, [[pankeratin]] -ve
+| EM         =
+| Molecular  =
+| IF         =
+| Gross      =
+| Grossing   =
+| Site       = [[kidney]] - see ''[[kidney tumours]]''
+| Assdx      = [[diabetes mellitus]], history of UTI, [[nephrolithiasis]], GU obstruction (various causes)
+| Syndromes  =
+| Clinicalhx =
+| Signs      =
+| Symptoms   =
+| Prevalence = uncommon
+| Bloodwork  =
+| Rads       = dilated upper GU system
+| Endoscopy  =
+| Prognosis  =
+| Other      =
+| ClinDDx    = [[renal cell carcinoma]], [[pyelonephritis]]
+| Tx         = antibiotics, occasionally nephrectomy
+}}
+'''Xanthogranulomatous pyelonephritis''', abbreviated '''XGP''', is an inflammatory process of the [[kidney]] that can mimic [[renal cell carcinoma]].
+==General==
+*May mimic [[renal cell carcinoma]] - especially radiologically.
+*Usually lower pole.{{fact}}
+*Associated with:
+**[[Diabetes mellitus]].
+**History of [[urinary tract infection]].<ref name=pmid17987581>{{cite journal |author=Afgan F, Mumtaz S, Ather MH |title=Preoperative diagnosis of xanthogranulomatous pyelonephritis |journal=Urol J |volume=4 |issue=3 |pages=169–73 |year=2007 |pmid=17987581 |doi= |url=}}</ref>
+**[[Nephrolithiasis]].
+**GU obstruction.<ref name=pmid17098659>{{cite journal |author=Al-Ghazo MA, Ghalayini IF, Matalka II, Al-Kaisi NS, Khader YS |title=Xanthogranulomatous pyelonephritis: Analysis of 18 cases |journal=Asian J Surg |volume=29 |issue=4 |pages=257–61 |year=2006 |month=October |pmid=17098659 |doi= |url=}}</ref>
+*Occasionally an indication for nephrectomy.<ref name=pmid17987581/><ref name=pmid17098659/>
+*Most common organism (in the context of nephrectomy specimens) - ''Proteus mirabilis''.<ref name=pmid17098659/>
+==Microscopic==
+Features:
+*Abundant (foamy) macrophages.
+**Associated with the collecting system - medulla, not cortex.
+*+/-Giant cells.
+*+/-Interstitial lymphocytes and plasma cells.
+*+/-Interstitial fibrosis.
+*+/-Cholesterol clefts (common).
+*+/-Calcifications - dystrophic.
+DDx:
+*[[Malakoplakia]].
+**Basophilic inclusions -- inside or outside of macrophages - often size of RBC or larger ([[Michaelis-Gutmann bodies]]).
+*[[Renal cell carcinoma]] - especially [[papillary RCC]] (as this has foamy macrophages).
+*[[Granulomatous disease]].
+*[[Chronic pyelonephritis]].
+*[[Interstitial nephritis]].
+*[[Renal cell carcinoma]] - foamy macrophages may be abundant.<ref name=pmid8378177>{{Cite journal  | last1 = Iskandar | first1 = SS. | last2 = Prahlow | first2 = JA. | last3 = White | first3 = WL. | title = Lipid-laden foamy macrophages in renal cell carcinoma. Potential frozen section diagnostic pitfall. | journal = Pathol Res Pract | volume = 189 | issue = 5 | pages = 549-52 | month = Jun | year = 1993 | doi = 10.1016/S0344-0338(11)80364-X | PMID = 8378177 }}</ref>
+===Images===
+<gallery>
+Image:Xanthogranulomatous_pyelonephritis_cd68.jpg | Xanthogranulomatous pyelonephritis - CD68 stain. (WC/Nephron)
+</gallery>
+www:
+*[http://www.archivesofpathology.org/na101/home/literatum/publisher/pinnacle/journals/content/arpa/2011/15432165-135.5/2009-0769-rsr.1/production/images/large/i1543-2165-135-5-671-f01.jpeg Several images of XGP (archivesofpathology.org)].<ref name=pmid21526966>{{Cite journal  | last1 = Li | first1 = L. | last2 = Parwani | first2 = AV. | title = Xanthogranulomatous pyelonephritis. | journal = Arch Pathol Lab Med | volume = 135 | issue = 5 | pages = 671-4 | month = May | year = 2011 | doi = 10.1043/2009-0769-RSR.1 | PMID = 21526966 }}</ref>
+==Stains==
+*[[PAS-D]] -ve.
+**Done to look for malakoplakia.
+==IHC==
+*CD68 +ve.
+*RCC markers (CD10, RCC) all negative.
+==Sign out==
+<pre>
+RIGHT KIDNEY, NEPHRECTOMY:
+- XANTHOGRANULOMATOUS PYELONEPHRITIS.
+- CHRONIC INTERSTITIAL NEPHRITIS.
+- INCREASED NUMBERS OF TOTALLY SCLEROSED GLOMERULI AND GLOMERULI WITH FOCAL
+  SCLEROSIS.
+- MARKED INTERSTITIAL FIBROSIS.
+- NEGATIVE FOR MALIGNANCY.
+COMMENT:
+Immunostaining demonstrates abundant CD68 positive cells (macrophages).  A CD10 immunostain
+is non-concerning (it highlights glomeruli). A pankeratin immunostain is non-concerning
+(it highlights benign renal tubules).
+</pre>
+===Compatible XGP===
+<pre>
+"KIDNEY" LESION, LEFT, BIOPSY:
+- FIBROMUSCULAR TISSUE WITH A MIXED INFLAMMATORY INFILTRATE.
+- CELLULAR DEBRIS WITH SURROUNDING LOOSELY AGGREGATED HISTIOCYTES.
+- NO RENAL PARENCHYMA IDENTIFIED.
+- NEGATIVE FOR MALIGNANCY.
+COMMENT:
+A SMA immunostain highlights the muscle component, and a CD68 immunostain marks
+abundant histiocytes. No epithelial component is identified with a pankeratin
+immunostain.
+</pre>
+===Micro===
+The sections show degenerative renal parenchyma with surrounding histiocytes, other inflammatory cells, fibrosis and cholesterol clefts.
+==See also==
+*[[Kidney tumours]].
+*[[Acute pyelonephritis]].
+*[[Xanthogranulomatous cystitis]].
+==References==
+{{Reflist|2}}
 [[Category:Diagnosis]]
+[[Category:Kidney tumours]]