Dr. med. Dirk Manski

 You are here: Urology Textbook > Kidneys > Xanthogranulomatous pyelonephritis

Xanthogranulomatous Pyelonephritis

Review literature: (Bingol-Kologlu et al, 2002) (Zorzos et al, 2003).

Definition of Xanthogranulomatous Pyelonephritis

Xanthogranulomatous pyelonephritis (XP) is a rare form of chronic pyelonephritis with foam cells (large macrophages with foamy lipid-containing cytoplasm), which leads to kidney destruction.


XP is rare (incidence 1.4/100000), women are more likely affected than men.


XP is usually a unilateral renal disease, which develops in nonfunctioning kidneys with nephrolithiasis, urinary tract infection and upper urinary tract obstruction. The most commonly isolated bacterial organisms are E. coli, Proteus, Klebsiella and Staphylococcus.

Pathology of of Xanthogranulomatous Pyelonephritis

Gross Pathology:

Enlarged kidney, enlarged renal pelvis filled with pus (pyonephrosis), orange-yellow inflammatory lesions in addition to tissue necrosis and small abscesses. The renal involvement is limited initially to segments of the kidney, later the inflammatory process involves most of the kidney. Hereby, the renal parenchyma is replaced by a granulomatous inflammatory tissue and loses its function. The disease may spread into adjacent structures of the retroperitoneum.


The inflammatory tissue contains neutrophils, lymphocytes, plasma cells, necrosis, and large macrophages with foamy lipid-containing cytoplasm. Sometimes epitheloid granulomas are found.

Signs and Symptoms of Xanthogranulomatous Pyelonephritis

Diagnostic Work-up

Urine sediment:

Urine sediment shows leukocyturia, bacteriuria, and possibly the detection of foam cells (lipid-laden macrophages).

Urine culture:

Urine culture has a low specifity, but often positive.

Laboratory tests:

leukocytosis, increased ESR, increased CRP, blood culture in patients with fever.

Renal ultrasound:

Renal ultrasound shows an enlarged kidney with a mixed echogenic mass, it cannot be reliably distinguished from a malignant tumor. Nephrolithiasis may be seen.

Intravenous urography:

KUB x-ray may show an increased renal shadow and nephrolithiasis. Urogram reveals in 30-80% a missing renal function with no opacification of the affected side.

Computed tomography:

CT is the diagnostic tool of choice. It shows a lesion of the kidney with inhomogeneous contrast enhancement, reduced kidney function, hydronephrosis and detection of nephrolithiasis. In some cases, renal cell carcinoma cannot be ruled out.


MRI is an alternative to CT, especially in renal failure.

Renal scintigraphy:

To clarify the remaining kidney function, when organ preservation seems possible.

Treatment of Xanthogranulomatous Pyelonephritis

Standard therapy for xanthogranulomatous pyelonephritis is nephrectomy or rarely partial nephrectomy. Surgery is difficult because of adhesions, a laparoscopic approach is not recommended. Perioperative antibiotic therapy is important, which may be modified after the results of intraoperative swab tests. In individual cases, it was possible to cure segmental XP with antibiotic therapy and internal splinting.

Index: 1–9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


Bingol-Kologlu u.a. 2002 BINGOL-KOLOGLU, M. ; CIFTCI, A. O. ; SENOCAK, M. E. ; TANYEL, F. C. ; KARNAK, I. ; BUYUKPAMUKCU, N.:
Xanthogranulomatous pyelonephritis in children: diagnostic and therapeutic aspects.
In: Eur J Pediatr Surg
12 (2002), Nr. 1, S. 42–8

Analysis of 39 cases of xanthogranulomatous pyelonephritis with emphasis on CT findings.
In: Scand J Urol Nephrol
37 (2003), Nr. 4, S. 342–7

  Deutsche Version: Xanthogranulomatöse Pyelonephritis