US and CT findings of xanthogranulomatous pyelonephritis

Systemic Amyloid A Amyloidosis Secondary to Xanthogranulomatous Pyelonephritis

The combination of systemic amyloid A (AA) amyloidosis and xanthogranulomatous pyelonephritis (XGP) resulting from a chronic urinary tract infection is extremely rare. We herein report a case of systemic AA amyloidosis secondary to XGP for which clinical remission developed after nephrectomy. To our knowledge, this is the first case report describing the clinical improvement of systemic AA amyloidosis secondary to XGP after nephrectomy in Japan. Clinicians should be aware of this uncommon combination and search for amyloid depositions in cases of XGP.

Xanthogranulomatous pyelonephritis combined with emphysematous pyelonephritis: A rare case report

Background:

Xanthogranulomatous pyelonephritis (XGP) is a rare and intense type of chronic kidney infection characterized by subversion of the renal tissue and its replacement by lipid- laden macrophages. XGP combined with emphysematous pyelonephritis(EPN) is rare and up until now only 7 cases with these presentations have been reported; so abundant clinical skills and appropriate radiographic imaging is required to reach the correct diagnosis. In this report, we present a case with two uncommon variants of pyelonephritis.

Case Presentation:

A 55-year-old female presented with a history of type 2 diabetes mellitus, and a stroke leading to a left-sided hemiplegia state for 7 years, coronary artery bypass grafting(CABG), hypertension(HTN) , seizure, progressive fatigue, loss of appetite , fecal and urinary incontinence and right costovertebral angle tenderness. According to clinical signs, symptoms and documentation of gas within the renal parenchyma on computed tomography (CT) of abdomen, of EPN diagnosis was suggested; however histopathologic evaluation showed acute emphysematous pyelonephritis on chronic xanthogranulomatous pyelonephritis.

Conclusion:

EPN can emerge in a patient suffering from XPG which would add to the severity of the situation. In the case presented, concurrent underlying diseases such as diabetes mellitus, stroke, CABG, HTN along with severe fatigue and loss of appetite existed. Surgical treatment produces dramatic results.

Xanthogranulomatous pyelonephritis in a pediatric patient

Introduction:

Xanthogranulomatous pyelonephritis consists of a chronic infectious and inflammatory process of the renal parenchyma, a variant of chronic obstructive pyelonephritis. It is more prevalent in middle-aged adults, rare in pediatric patients, with less than 300 cases reported in children worldwide.

Report:

Preschooler, aged 2 years and 11 months, male, with 2 months of abdominal distention, increased temperature and intense pallor, associated with microcytic anemia refractory to the use of ferrous sulfate. 1 week before, he had a bulging in his left flank and a hard palpable mass there. Imaging exams (ultrasound and tomography) revealed an overall enlargement of the left kidney, destruction of the renal parenchyma and intense calyceal dilation, forming the "bear's paw" sign, with a staghorn calculus in the pelvis. He underwent treatment with antibiotic therapy and total nephrectomy, with a specimen sent for pathological examination.

Discussion:

a disease of uncertain incidence in the pediatric age group, xanthogranulomatous pyelonephritis is more prevalent in male children and affects mainly the left kidney, being frequently associated with the presence of stones. Clinically, it has nonspecific symptoms, the most common being abdominal distension and asthenia. Laboratory exams shows microcytic, leukocytosis, thrombocytosis and increased inflammation, pyuria, hematuria and proteinuria, in addition to bacterial growth in urine culture. The diagnosis is anatomopathological, but it can be hinted by contrasted CT scan, with the classical sign of the "bear's paw". Treatment may include nephrectomy and broad-spectrum antibiotic therapy.

Xanthogranulomatous pyelonephritis: a focus on microbiological and antibiotic resistance profiles

BACKGROUND

Xanthogranulomatous pyelonephritis (XGP) is an inflammatory condition of the kidney and its treatment most often involves a combination of antibiotics and nephrectomy. This study aimed to define the clinical features and management of XGP, focusing on microbiological aspects and antibiotic therapy.

METHODS

We performed a retrospective study of 27 cases of XGP diagnosed between January 2001 and January 2020 to analyse their clinical and management characteristics. In addition, a literature review was conducted of XGP case series covering the period from 2000-2020. We searched PubMed for case series through April 2020 without language restrictions. Studies reporting case series of XGP (more than ten cases) were included if they were relevant to this study.

RESULTS

Twenty-seven patients were diagnosed with XGP, and 26 of them were histologically proven to have XGP. A total of 81.5% of the patients were female and the mean age was 59.6 years (SD 19.2). The most frequent symptoms were flank pain (70.4%) and fever (59.3%), while 77.8% of patients had renal stones. Proteus mirabilis was detected in the urine culture in 18.5% of patients, followed by detection of Escherichia coli in 14.8% of patients. The computed tomography (CT) findings included perirenal (29.6%) or pararenal (29.6%) involvement in the majority of patients. Twenty-six patients underwent nephrectomy. Piperacillin/tazobactam and ceftriaxone were the most commonly prescribed antibiotics for treatment. The reported piperacillin/tazobactam and ceftriaxone resistance rates were 14.3% and 16.6%, respectively. Twenty-six case series were included in the literature review, reporting 693 cases in total.

CONCLUSION

We found well-established characteristics of XGP patients among series in terms of previous history, clinical, laboratory and imaging findings, and operative and postoperative outcomes. It is important to know the clinical presentation and potential severity of XGP, as well as the most frequently involved microorganisms and their antibiotic resistance profiles, to select the most appropriate antibiotic therapy.

Complicated pyelonephritis associated with chronic renal stone disease

Purpose

This article reviews imaging manifestations of complicated pyelonephritis associated with chronic renal stones disease, in particular xanthogranulomatous pyelonephritis (XGP) and emphysematous pyelonephritis (EPN), as potential mimics of other renal diseases and malignances and provides helpful tips and differentiating features that may alert the radiologist to suspect a diagnosis of infection.

Materials and methods

A retrospective review of the records from 6 adult patients (5 females and 1 male, mean age 72,3 years) with diagnosis of XGP associated with chronic nephrolithiasis and 7 adult patients (6 females and 1 male, mean age 59,3 years) with diagnosis of EPN associated with chronic nephrolithiasis from January 2010 to January 2020 was carried out. Computed tomography urography (CTU) with at least an unenhanced scan, and the parenchymal and excretory phases after contrast medium administration performed at our Teaching Hospital were included. When available images related to conventional radiography, ultrasound (US) and magnetic resonance imaging of the same patients, the comparison with CTU images was carried out.

Conclusion

A possible diagnosis of XGP or EPN must always be taken into account when a pyelonephritis is associated with untreated kidney stones, especially whenever clinical presentation is atypical, current therapy is not effective and imaging shows features of dubious interpretation. Due to their rarity and atypical presentation, a multidisciplinary approach is required and an expert radiologist represents a key figure in the multidisciplinary team as he can help to differentiate between benign and malignant lesions and thus avoid unnecessary radical surgical procedures.

Postpartum xanthogranulomatous pyelonephritis: A case report

Xanthogranulomatous pyelonephritis (XGP) is seldom seen nowadays due to the aggressive treatment of upper urinary tract infections as well as recent advances in the management of urolithiasis. It has been rarely reported in the peri-partum period. We present a case of XGP without any evidence of renal calculi, manifesting in a 26-year-old previously healthy woman immediately post-partum.

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Xanthogranulomatous pyelonephritis is rare due to the aggressive treatment of upper urinary tract infections and urolithiasis.

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It has been rarely reported in the peri-partum period.

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A post-partum 26-year-old woman developed acute xanthogranulomatous pyelonephritis, without any evidence of renal calculi.

Effect of Kidney Volume on the Results of Nephrectomy Performed for Xanthogranulomatous Pyelonephritis

Aim

This study aims to evaluate the results of patients we treated with nephrectomy due to Xanthogranulomatous pyelonephritis (XGP) and the effects of kidney volume on the results.

Patients and methods

Records of 22 patients who underwent nephrectomy due to renal masses at our clinic between January 2008 and May 2018 and whose pathology results indicated XGP were retrospectively evaluated. The computed tomography (CT) measurement of the kidney volumes of the patients was calculated as the product of the longest length, width, and height of the kidney. The mean kidney volume of the patients was calculated and the patients were distributed into two groups: those that presented volumes below average (Group 1) and above average (Group 2). The patients’ mean ages, operative duration, hospitalization days, differences in pre- and postoperative hemoglobin and creatinine levels, and postoperative complications were compared across groups.

Results

Group 1 consisted of 12 patients and Group 2 of 10 patients. The mean kidney volume of the patients was calculated as 33.4 cm³ ± 26.0 cm³. The mean kidney volume of the patients was 15.8 cm³± 9.9 cm³ in Group 1 and 56.8 cm³ ± 21.8 cm³ in Group 2. There were no statistical differences between the two groups in terms of operative times, preop-postop hemoglobin (Hgb) levels and complications.

Conclusion

In cases where XGP is considered probable, the priority in preoperative CT must be to thoroughly evaluate the relationship of the kidney with the surrounding tissue and organs rather than to investigate the patients’ kidney volumes.

Urinothorax Caused by Xanthogranulomatous Pyelonephritis

Xanthogranulomatous pyelonephritis is a rare form of chronic pyelonephritis that generally afflicts middle-aged women with a history of recurrent urinary tract infections. Its pathogenesis generally involves calculus obstructive uropathy and its histopathology is characterized by replacement of the renal parenchyma with lipid filled macrophages. This often manifests as an enlarged, nonfunctioning kidney that may be complicated by abscess or fistula. This case details the first reported case of xanthogranulomatous pyelonephritis complicated by urinothorax, which resolved on follow-up chest X-ray after robot-assisted nephrectomy.

Xantogranulomatous pyeloneprhritis in children

Abstract

Xanthogranulomatous pyelonephritis (XPN) is an unusual and severe form of chronic inflammatory lesion of the kidney, characterised by the destruction of the renal parenchyma and the presence of multinucleated giant cells and lipid-laden macrophages, inflammatory infiltration and intensive renal fibrosis. There are a few cases in the literature which describe the disease in children. The pathomechanism of XPN is poorly understood. Renal obstruction with concomitant urinary tract infection is the most commonly associated pathological finding. The process is typically unilateral and may be focal or diffuse. In both cases, the perirenal infiltration is possible and can be mistaken for common renal neoplasm or inflammatory process. The symptoms are non-specific. Diagnostic imaging techniques with clinical suspicion have enabled XPN to be diagnosed and differentiated from malignancy with a high degree of confidence. Computed tomography (CT) is the mainstay of diagnostic imaging. The definitive diagnosis of XPN is based on pathological assessment after nephrectomy. We review and illustrate the clinical, radiological, surgical and pathological characteristics of XPN in children. All cases shown are surgically and histopathologically proven.

Teaching Points

• XPN can present different clinical manifestations.

• CT is the mainstay of diagnostic imaging in XPN.

• Focal type of XPN should be included in the differential diagnosis of children with a renal mass.

• There are no clear guidelines on the management of XPN.

• Conservative and surgical treatments should be considered for each individual case.

• Histopathological examination confirms the diagnosis and excludes other benign and malign diseases.

Xanthogranulomatous pyelonephritis presenting as acute pleuritic chest pain: a case report

Background

Xanthogranulomatous pyelonephritis is a rare and serious manifestation of chronic kidney inflammation that can be life-threatening if not recognized and treated appropriately, often with antibiotics and surgery. Affected patients are most commonly females in their fifth or sixth decade of life with a background of obstructive uropathy, nephrolithiasis, or recurrent urinary tract infections who present with vague nonspecific symptoms.

Case presentation

A 43-year-old woman of Russian ethnicity with a history of nephrolithiasis presented to our emergency department with new left-sided pleuritic chest pain amid a 6-week history of constitutional symptoms including fevers, night sweats, and 7 kg of weight loss. Workup for acute coronary syndrome and pulmonary embolism in our emergency department was negative. Given that she was clinically unwell, she was admitted to internal medicine to expedite workup for the cause of her symptoms. A broad differential diagnosis for various infectious, inflammatory/autoimmune, and neoplastic processes was considered. Based on classic radiographic and histopathologic findings, she was ultimately diagnosed with xanthogranulomatous pyelonephritis of her left kidney, which was a direct consequence of chronic inflammation. This inflammation exhibited spread to local tissues and across her left hemidiaphragm, resulting in a unilateral pleural effusion which explained her chest discomfort. She was treated with antibiotics administered intravenously and urgent total nephrectomy with a good functional outcome.

Conclusions

Our case illustrates an uncommon but clinically important do-not-miss diagnosis that underlies a common clinical presentation of pleuritic chest pain. The case underscores the importance of maintaining a broad differential diagnosis and organized approach when treating patients with undifferentiated clinical presentations.

Xanthogranulomatous pancreatitis mimicking a malignant solid tumour

Xanthogranulomatous inflammation, which is known to occur in several viscera, is rarely found to affect the pancreas. We report a case of xanthogranulomatous pancreatitis (XGP) occurring in a 60-year-old man who presented with epigastric pain and vomiting. Physical examination did not reveal any abnormality. Contrast-enhanced CT of the abdomen revealed an ill-defined, heterogeneous mass lesion in the uncinate process of the pancreas, suggestive of malignancy. Whipple's pancreaticoduodenectomy was performed and the final pathological diagnosis was XGP. The patient's postoperative course was uneventful. When a pancreatic mass does not show clinicoradiological features typical of common pancreatic neoplasms, XGP should be considered for a differential diagnosis and duodenum preserving surgery can be considered.

A 13-Month-Old With Xanthogranulomatous Pyelonephritis With Features of Renal Malakoplakia

Xanthogranulomatous pyelonephritis is an uncommon chronic inflammatory renal disorder caused by chronic infection with gram-negative bacteria leading to destruction of the renal parenchyma and replacement with foamy lipid-laden macrophages. Renal malakoplakia is another rare form of chronic inflammatory granulomatous disease in the kidney associated with infection usually occurring in adults with immunocompromised status or debilitating disease. It is hallmarked by the finding of foamy histiocytes with distinctive basophilic inclusions (Michaelis-Gutmann bodies). We present a case of a 13-month-old male with history of congenital hydronephrosis who presented with clinical and radiologic findings suggestive of xanthogranulomatous pyelonephritis. However, further pathologic studies revealed the presence of Michaelis-Gutmann bodies, which are pathognomonic for renal malakoplakia. With this case we hope to bring further evidence to support that these two conditions are not mutually exclusive but rather represent two pathologic processes on the same disease spectrum.

Xantogranulomatous pyelonephritis: The missed diagnosis

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Xantogranulomatous pyelonephritis (XGPN) is a rare chronic inflammatory disease of the kidney.

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The focal form imitates greatly renal cell carcinoma (RCC).

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We report a challenging clinical case of a 38-year old with lack of history of stone disease or urinary tract infection.

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Preoperative diagnosis of focal XGPN was difficult because of radiological similarities to RCC.

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An open right radical nephrectomy including the adrenal in the resection was performed and final histology revealed a focal renal mass which consist with a xantogranulomatous pyelonephritis.

Introduction

Xantogranulomatous pyelonephritis (XGPN) is a rare chronic inflammatory disease of the kidney that can be focal or diffuse with the focal form imitating greatly renal cell carcinoma (RCC).

Presentation of case

We report a challenging clinical case of a 38-year old male with right flank pain persisting for 3-months, imaging showed an 8 cm heterogenous mass of the upper pole of the right kidney and invading the liver. A right radical nephrectomy including the adrenal in the resection was performed under the tentative diagnosis of renal cell carcinoma (RCC) whereas histology revealed focal XGPN.

Discussion

Preoperative diagnosis of focal XGPN was difficult because of radiological similarities to RCC and lack of history of stone disease or urinary tract infection.

Conclusion

This case highlights the need to include XGPN in the differential diagnosis of RCC even in the era of modern imaging.

Xanthogranulomatous Pyelonephritis Associated with Hepatic Dysfunction in Pregnancy

Xanthogranulomatous pyelonephritis is a rare disease characterised by the replacement of normal renal parenchyma by foamy macrophages. The only treatment for this type of pyelonephritis is of a surgical nature with partial or total nephrectomy. The occurrence of xanthogranulomatous pyelonephritis during pregnancy is a rare event (with only 6 cases described in the literature). We report a case of xanthogranulomatous pyelonephritis in a 32-week pregnant woman associated with hepatic dysfunction.

Xanthogranulomatous pyelonephritis in Korean children

PURPOSE

Xanthogranulomatous pyelonephritis (XGP) is rare among children. In most cases, XGP is diffusely or focally enlarged, mimicking the neoplastic process. The aim of this study was to examine clinical characteristics and outcomes of Korean children with XGP.

MATERIALS AND METHODS

Fourteen children (9 boys, 5 girls) with XGP were reviewed retrospectively. The cohort included 2 children managed at our institution and 12 children reported in the Korean literature. The patients' records were reviewed with respect to age at diagnosis, clinical presentation, management method, and other characteristic features.

RESULTS

The mean age was 79.4±66.5 months (range 1-168 months). Common clinical presentations included fever (85.7%), abdominal pain (57.1%), and palpable mass (28.6%). Laboratory abnormalities included leukocytosis (57.1%), anemia (57.1%), and pyuria (57.1%). The types of XGP that were diagnosed based on preoperative radiologic studies included the focal form in 9 children and the diffuse form in 5. Thirteen children underwent nephrectomy, and 1 child received conservative medical therapy.

CONCLUSION

The possibility of XGP should be considered if a child is diagnosed with a renal mass, especially if it is a small renal mass associated with fever, leukocytosis, or stone. Nephrectomy is the treatment of choice for the diffuse form, whereas partial nephrectomy or conservative medical therapy may be indicated to manage focal XGP.

Infectious and inflammatory diseases of the kidney

Although the most common renal infection, acute pyelonephritis, can typically be diagnosed on clinical and laboratory examinations, radiologic studies play a role in evaluating for complications and in examining the high-risk patient for more serious complications and atypical infections. It is imperative that the radiologist be familiar with renal infections beyond the common acute pyelonephritis.

Xanthogranulomatous pyelonephritis in a young postpartal female

Xanthogranulomatous pyelonephritis (XGP) is a rare chronic inflammatory disorder of the kidney characterised by an infectious phlegmon arising in the renal parenchyma. It is seen in patients who have urolithiasis, urinary tract infection and immunocompromised status. The clinical presentation is variable and renal neoplasm is considered as a differential due to its characteristic extrarenal visceral invasion. The treatment is almost universally extirpative and can pose a formidable challenge to the treating physician and surgeon. The authors report a rare case of XGP in a postpartal woman who presented with multiple visceral abscesses whose diagnosis was arrived on histopathological examination.

Xanthogranulomatous pyelonephritis: critical analysis of 30 patients

INTRODUCTION AND OBJECTIVE

Xanthogranulomatous pyelonephritis (XGP) is a chronic inflammatory condition of the kidneys. Nevertheless, disparities between the pre-operative and pathological diagnoses are frequently encountered. We reviewed all patients with XGP over a 17-year period to identify and characterize the pre-operative and pathological characteristics of the disease in our patients.

METHODS

A comprehensive review of all nephrectomy patients with a pre-operative diagnosis of pyelonephritis at National Taiwan University Hospital from 1991 to 2008 with the pathological diagnosis of XGP was conducted to demonstrate the clinical and radiological characteristics of XGP.

RESULTS

XGP was diagnosed in 30 (18.6%) of the 160 nephrectomies performed for pyelonephritis. Of the 30 patients with XGP, 25 were women (83.3%) and 20 (66.7%) were overweight (body mass index >23). Their mean age was 55.17 years. The average serum creatinine level was 1.68 mg/dL. The image findings included renal calculi (56.7%), staghorn stones (26.7%), and spread of the disease to the retroperitoneum and psoas muscle (33.3%). Escherichia coli (36.7%) was the most prevalent pathogen. The mortality of the two-stage surgical treatment was zero, and morbidity developed in only 1 patient (4.8%).

CONCLUSION

The key to accurate pre-operative diagnosis is to keep risk factors in mind such as age, sex, and renal calculi. Clinicians should maintain a high suspicion of XGP for early recognition and be aware of the care of chronic kidney disease. Finally, the association between XGP and central obesity warrants further research.

CT imaging of mass-like renal lesions in children

Mass-like renal lesions in children occur in a diverse spectrum of conditions including benign and malignant neoplasm, infection, infarction, lymphatic malformation, and traumatic injury. Although mass-like renal lesions can sometimes be suspected on plain radiographs and evaluated with US in children, subsequent CT is usually performed for the confirmation of diagnosis and further characterization. The purpose of this pictorial essay was to review the CT imaging findings of both common and uncommon mass-like renal lesions in pediatric patients. Understanding the characteristic CT appearance of mass-like renal lesions in children enables an accurate diagnosis and optimizes patient management.

Renal parenchymal malacoplakia: a different stage of xanthogranulomatous pyelonephritis?

Malacoplakia is a rare inflammatory condition characterized by demonstrative Michaelis-Gutmann bodies, which are foamy histiocytes with distinctive basophilic inclusions. Malacoplakia is caused by the inadequate elimination of bacteria by macrophages or monocytes as a result of defective phagocytic activity. Xanthogranulomatous pyelonephritis is characterized by the destruction of renal parenchyma and its replacement by solid sheets of foamy lipid-laden macrophages. Prolonged infection of the kidney, which is frequently caused by an obstruction of the urinary tract, is the pathologic mechanism of that condition. We present a 6-year-old patient with a poorly functioning kidney who had a prolonged recurrent urinary tract infection. The results of histologic analysis revealed an inflammatory infiltration consisting predominantly of foamy and epithelioid histiocytes that contained round intracytoplasmic concretions characteristic of Michaelis-Gutmann bodies. We suggest that malacoplakia might be a stage of xanthogranulomatous pyelonephritis.

Xanthogranulomatous pyelonephritis in adults: clinical and radiological findings in diffuse and focal forms

AIM

To describe the clinical and radiological features of focal and diffuse xanthogranulomatous pyelonephritis (XGP) in adults.

MATERIALS AND METHODS

A retrospective review of the clinical data, laboratory findings, imaging features, and surgical treatment of 13 cases of histologically proven XGP diagnosed between January 1993 and December 2005 was undertaken. There were 10 women and three men with a mean age of 55.2 years (range 30-87 years). All patients underwent both sonography and computed tomography (CT) of the kidneys. Magnetic resonance imaging (MRI) was performed in two patients.

RESULTS

XGP was diffuse in 11 patients and focal in two patients. Fever, anorexia and weight loss, urinary symptoms, and flank pain were the most common manifestations. Urinary tract infection was found in eight patients. Sonography and CT showed diffuse kidney enlargement in seven cases and atrophy in five cases; a solitary solid mass was found in two patients. Hydronephrosis was noted in nine cases, staghorn calculus in six, and extensive pararenal disease in six. MRI failed to provide the preoperative diagnosis in the two patients with focal XGP. Total or partial nephrectomy was performed without postoperative complications.

CONCLUSION

Although rare, XGP is the main differential diagnosis of malignant renal neoplasia. The definitive diagnosis depends on histological examination of the operative specimen. Preoperatively, the diagnosis can often be suspected based on imaging studies, primarily CT.

Ultrasonographic evaluation of renal infections

Renal sonography can be easily performed and provides valuable information concerning the underlying disease process, helping to decide appropriate management. This article reviews the important renal infections, such as pyelonephritis, emphysematous pyelonephritis, renal abscess, hydatid disease, renal tuberculosis, pyonephrosis, and HIV-associated nephropathy.

Xanthogranulomatous pyelonephritis

Xanthogranulomatous pyelonephritis is a rare condition in children. A 7-year-old boy developed right flank pain and tenderness 1 month after an appendectomy. Abdominal computed tomography scan documented a right renal mass. A right nephrectomy was performed. The pathological report documents xanthogranulomatous pyelonephritis. He experienced an uneventful recovery. Xanthogranulomatous pyelonephritis should be included in the differential diagnosis of children with fever, weight loss, flank tenderness, and a renal mass.

[Atypic radiologic aspect of a renal cell carcinoma in children]

Renal cell carcinoma is rare in children and is usually found in late childhood. The authors report on an exceptional case of renal cell carcinoma in a 10-year-old girl. The radiological aspect is misleading and has not been previously reported in the literature. Renal cortex was thin because of congenital megalo-ureter, so the tumor developed entirely into excretory cavities (to the proximal ureter), while a primitive urothelial disease (tumoral or inflammatory) was first evoked. The atrophied cortex was the tumoral starting point which prolapsed into excretory cavities, upraising the urothelial epithelium.

Xanthogranulomatous pyelonephritis with nephrocutanous fistula and coexisting renal replacement lipomatosis

Renal replacement lipomatosis (RRL) is the result of rare, usually unilateral, and severe atrophy and destruction of the renal parenchyma often caused by renal calculi. It may be associated with, sometimes, aging, atrophy, long-standing chronic inflammation and urinary infection, such as renal tuberculosis. We report magnetic resonance (MR) and computed tomography (CT) findings of our case, which has xanthogranulomatous pyelonephritis (XGP) and RRL additionally associated with nephrocutanous fistula.

[Diffuse xanthogranulomatous pyelonephritis with a renocolic fistula neglected for more than two years]

INTRODUCTION

Although reno-colic fistula is a well-known complication of the diffuse form of xanthogranulomatous pyelonephritis, the features of the case here presented are unusual because of the paucity of symptoms and long lasting evolution of the disease before it was diagnosed.

CLINICAL CASE

A 75 year-old woman was seen at the emergency room complaining of fever and malaise. Physical and laboratory examination showed anemia and a left abdominal mass, and on X-ray and abdominal CT, a gross stone and huge left renal and extrarenal xanthogranulomatous pyelonephritis with renocolic fistula were disclosed. A review of her clinical record showed an X-ray performed two years before by the attending family clinician, with identical gross calculi and gas into the kidney. Nephrectomy, caudal pancreatectomy and partial colectomy were accomplished with good results.

COMMENT

This case of poor-symptomatic xanthogranulomatous pyelonephritis that destroyed the kidney and induced a renocolic fistula, is unusual because it was neglected for more than two years due to unawareness of the clinical and radiological picture.

Imaging of renal tumours in infancy and childhood

There is a large range of benign and malignant renal neoplasms. This article lists the most benign, indeterminate and malignant renal tumours that occur during infancy and childhood. It briefly describes the most important entities, including their imaging features, and important complications. Differential diagnosis and pitfalls are discussed, and a brief suggestion for a standardised imaging algorithm is proposed. Although modern imaging techniques, including colour Doppler sonography, helical or multidetector CT, and MR have significantly improved imaging potential, the definite diagnosis on tumour entity still is established only by histology.

Ultrasonographic features of focal xanthogranulomatous pyelonephritis

OBJECTIVE

To analyze the ultrasonographic features of focal xanthogranulomatous pyelonephritis.

METHODS

Ultrasonographic features of 15 patients with pathologically proved focal xanthogranulomatous pyelonephritis were retrospectively analyzed by 2 radiologists who reached a consensus, in terms of the location, margin, size, and echo texture of the mass, associated calculi, lymphadenopathy, or local extension, in comparison with computed tomographic and clinical findings.

RESULTS

At ultrasonography, 12 (80%) of 15 masses were well circumscribed. The maximal sizes of the masses ranged from 2.5 to 5.8 (mean, 3.8) cm. Thirteen solid masses (87%) were hyperechoic (n = 7), hypoechoic (n = 4), or isoechoic (n = 4) to the renal cortex, and the preoperative diagnosis was either renal cell carcinoma (n = 11) or Wilms tumor (n = 2). The preoperative diagnosis of the other 2 cystic lesions (13%) was renal abscess. Renal calculi were found in 1 case, but lymphadenopathy or local extension was not depicted. Clinical inflammatory signs were found in 11 of 15 patients.

CONCLUSIONS

There were no specific ultrasonographic features that allow for the distinction between focal xanthogranulomatous pyelonephritis and renal tumors or abscesses. Focal xanthogranulomatous pyelonephritis should be considered when there are clinical signs of infection or inflammation and a focal solid mass is seen on ultrasonography.

Aspiration cytology of focal xanthogranulomatous pyelonephritis: A diagnostic challenge

A case of focal xanthogranulomatous pyelonephritis presenting as a circumscribed mass in a functioning kidney of a young male is described. Clinical, radiological, and cytological features closely mimicked renal cell carcinoma leading to radical nephrectomy. Peroperative findings and gross pathological features also corroborated preoperative diagnosis. The final diagnosis was a histologic surprise. It is an uncommon entity with cortical location, no pelvic communication, and progressively destroying the kidney. It should be considered in the differential diagnosis of any mass lesion at any age during preoperative clinicoradiological and cytological evaluation. A correct preoperative diagnosis can save unnecessary nephrectomy.

The role of computed tomography in modern paediatric uroradiology

Computed tomography (CT) has developed a well-recognised role within paediatric uroradiology, especially in imaging of trauma, malignancy (in particular Wilms' tumour), atypical infection, and congenital urogenital abnormalities. CT can also be used for problem solving in nephrolithiasis and renal transplant assessment. These applications are illustrated and discussed, with an emphasis on particular information that can be gained from the CT study.