Chronic pyelonephritis is a long-standing renal disorder characterized by tubulointerstitial inflammation with cortical scarring that eventually may result in end-stage renal disease. It includes variants like xanthogranulomatous pyelonephritis and emphysematous pyelonephritis. Diagnosis is based on renal function tests, urinalysis, urine culture, histopathology and radiological investigations.
Presentation
Chronic pyelonephritis (CP) is marked by chronic renal tubulointerstitial inflammation which leads to scarring within the renal cortex and calyceal clubbing. It may lead to end-stage renal disease (ESRD). The disease is also known as reflux nephropathy, interstitial nephritis, and chronic atrophic pyelonephritis. CP also includes rare variants like xanthogranulomatous pyelonephritis (XGP) and emphysematous pyelonephritis (EPN) [1]. The clinical presentation of CP is variable and non-specific. Some patients may be asymptomatic while others may present with malaise, fatigue, loss of appetite, loss of weight, cloudy urine, fever, backache, flank pain, or abdominal discomfort. In advanced stages of the disease, patients will have hypertension. XGP may be characterized by the presence of a unilateral palpable abdominal mass, while patients with EPN may present with signs of sepsis.
Chronic pyelonephritis may follow inadequate treatment or recurrence of acute pyelonephritis, composed of a localized immune response to bacteria that have been eradicated [2]. In children, the chief cause of CP is vesicoureteral reflux (VUR) and recurrent urinary tract infections (UTIs) associated with renal scarring [3] [4]. In adults, renal scarring is rarely due to urinary tract infections [5] [6].
Xanthogranulomatous pyelonephritis (XGP) is a rare variant of CP and may be associated with longstanding obstructive urinary tract disorders and Proteus infection [7].
Emphysematous pyelonephritis (EPN) is another rare, potentially life-threatening variant of CP. The disease develops secondary to renal parenchymal infection with E.coli, Klebsiella, or Proteus species. It is characterized by a sudden onset of acute necrotizing pyelonephritis and the presence of a renal parenchymal gas, usually in poorly controlled diabetics [8].
Entire Body System
- Chills
High fever and shaking chills also may be signs that your kidney infection has spread to your bloodstream and can travel to others parts of your body. [drugs.com]
Clinical features: Fever (usually high fever with chills and rigors). Dysuria. Hematuria. Pain in the costovertibral angle on the affected side. Presence of pus cell casts in urine analysis will show renal involvement. [hubpages.com]
[…] sample topics: -- The first section of this topic is shown below -- Basics Description A syndrome caused by infection of the renal parenchyma and/or renal pelvis, often producing localized flank/back pain combined with systemic symptoms, such as fever, chills [unboundmedicine.com]
Pyelonephritis (kidneys): This can cause fever, chills, nausea, vomiting, and pain in your upper back or side. Urethritis (urethra): This can cause a discharge and burning when you pee. [webmd.com]
Symptoms of a kidney infection include: Sudden onset of chills Fever over 100 degrees Fahrenheit Pain in the groin, lower back or side Nausea Vomiting Abdominal muscle spasm More general symptoms of upper kidney infection include: Flushed or reddened [my.clevelandclinic.org]
Gastrointestinal
- Nausea
Pyelonephritis can cause abdominal pain and tenderness, fever, nausea, confusion, fatigue, and an accelerated heart rate, all of which start to develop one to two days after the infection begins. [tgh.org]
In children, symptoms such as fever, lethargy, flank pain, and nausea may be present. [lecturio.com]
Often observed lethargy, decreased concentration, drowsiness or insomnia; periodic nausea and vomiting; increased susceptibility to infections; anemia; increased blood pressure, nosebleeds; losing weight. [acikgunluk.net]
Pyelonephritis presents with fever, accelerated heart rate, painful urination, abdominal pain radiating to the back, nausea, and tenderness at the costovertebral angle on the affected side. [dbpedia.org]
Common symptoms of a kidney infection are nausea, fatigue, and dull lower back pain. The kidneys are a component of the urinary system, which also includes the ureters, urinary bladder, urethra, and prostate (in men). [emedicinehealth.com]
- Abdominal Pain
Pyelonephritis can cause abdominal pain and tenderness, fever, nausea, confusion, fatigue, and an accelerated heart rate, all of which start to develop one to two days after the infection begins. [tgh.org]
Pyelonephritis presents with fever, accelerated heart rate, painful urination, abdominal pain radiating to the back, nausea, and tenderness at the costovertebral angle on the affected side. [dbpedia.org]
Some patients have fever, flank or abdominal pain, malaise, or anorexia. In XPN, a unilateral mass can usually be palpated. [msdmanuals.com]
- Right Flank Pain
CASE: A 45 year-old female presents with a two day history of dysuria, fevers, suprapubic discomfort, and right flank pain. She tells you that her symptoms are similar to a prior urinary tract infection (UTI) with the exception of the fever. [emdocs.net]
Cardiovascular
- Hypertension
Three patients with well documented unilateral chronic pyelonephritis (UCP) of bacterial origin, one hypertensive and two normo-tensive, were presented. Removal of the contracted kidney in the hypertensive patient did not eradicate the hypertension. [ncbi.nlm.nih.gov]
The diagnosis of chronic P. in patients with hypertension is quite complex, as it is mostly chronic P., accompanied by hypertension, is latent. [medicalency.com]
- Diastolic Hypertension
Chronic renal inflammation was associated with hydronephrosis, ureteral dilatation, acute pyelonephritis and diastolic hypertension. CONCLUSION: Chronic pyelonephritis and chronic renal inflammation are associated with long-term catheterization. [ncbi.nlm.nih.gov]
Musculoskeletal
- Back Pain
Suggestive symptoms : kidney pain (back pain), micturition disorders with polyuria (urinating more) and nocturia (urinating at night) and occasional appearances of polaki-disuria, pain during urination, pyuria (urine with pus). [bendomd.com]
Explore these free sample topics: -- The first section of this topic is shown below -- Basics Description A syndrome caused by infection of the renal parenchyma and/or renal pelvis, often producing localized flank/back pain combined with systemic symptoms [unboundmedicine.com]
Also call if your child develops new symptoms, such as: Back pain or flank pain Bad-smelling, bloody, or discolored urine Fever of 100.4°F (38°C) rectally in infants, or over 101°F (38.3°C) in children Low back pain or abdominal pain below the belly button [medlineplus.gov]
This 52-year-old white female complained of severe weakness and abdominal pain and, in addition, had suffered back pain for one month prior to admission. [pubs.rsna.org]
Some of the more common symptoms of kidney infection are: fever, chills, nausea, vomiting, generalized weakness, fatigue, a burning sensation with urination (dysuria), dull pain on the side or lower back pain (dull kidney pain), and dehydration. [emedicinehealth.com]
Neurologic
- Stroke
Ischemic Stroke % Hemorrhagic Stroke % Total % p No. [ncbi.nlm.nih.gov]
Other conditions that can boost your risk include hormone changes, multiple sclerosis, and anything that affects urine flow, such as kidney stones, a stroke, and a spinal cord injury. [webmd.com]
Acute cardiovascular events, especially stroke and myocardial infarction, account for about half of the deaths occurring in dialysis patients and also deaths after the first year post-transplantation. [meddean.luc.edu]
⩾ 40 years, autopsy was performed on 131 hypertensive patients during the 20 years after 1961, and the frequency of secondary hypertension was 3.8%, with that of renal hypertension being 3.1%. 645 Although the incidence of and mortality rates due to stroke [nature.com]
Urogenital
- Flank Pain
Chronic Pyelonephritis may come to attention during an episode of acute pyelonephritis with its attendant constitutional symptoms, flank pain, bacteruria, and pyuria. [pathwaymedicine.org]
Some patients may be asymptomatic while others may present with malaise, fatigue, loss of appetite, loss of weight, cloudy urine, fever, backache, flank pain, or abdominal discomfort. [symptoma.com]
Torsion : Ovarian and testicular torsion can present with flank pain. [emdocs.net]
In children, symptoms such as fever, lethargy, flank pain, and nausea may be present. [lecturio.com]
Patients typically present with flank pain, costovertebral angle tenderness, fever, and other features of cystitis (e.g., dysuria, frequency). Urinalysis reveals leukocyturia and bacteriuria. [amboss.com]
- Dysuria
It can present a wide variety of problems for patients such as recurrent dysuria, pain with intercourse, frequent small voids, and pelvic pain with negative urine cultures. [emdocs.net]
Dysuria. Hematuria. Pain in the costovertibral angle on the affected side. Presence of pus cell casts in urine analysis will show renal involvement. In lower urinary tract involvement there is only pus cells, no casts. [hubpages.com]
CLINICAL FEATURES ▪ May present with fever, flank pain ▪ Usually present with chronic renal failure or symptoms of hypertension ▪ frequency of micturition & dysuria 13. [slideshare.net]
Patients typically present with flank pain, costovertebral angle tenderness, fever, and other features of cystitis (e.g., dysuria, frequency). Urinalysis reveals leukocyturia and bacteriuria. [amboss.com]
There may or may not be accompanying lower urinary tract symptoms with frequency, dysuria, gross haematuria or hesitancy. [patient.info]
- Kidney Failure
If a person has a history of chronic kidney disease and kidney failure - the diet should be adjusted without fail. [acikgunluk.net]
Failure Risk Calculator Kidney Failure Risk Calculator Nephrology Self Assessment Quiz Nephrology Self Assessment Quiz Nephrology Nutrition Nephrology Nutrition Images in Nephrology Images in Nephrology Nephrology Articles Nephrology Articles Nephrology [ukidney.com]
All of the problems associated with kidney failure may develop and need to be managed carefully in the follow-up clinic. [kidneypatientguide.org.uk]
It often leads to complete kidney failure. [kidney.org]
Severe cases of pyelonephritis can lead to pyonephrosis (pus accumulation around the kidney), sepsis (a systemic inflammatory response of the body to infection), kidney failure and even death. [dbpedia.org]
- Cloudy Urine
Some patients may be asymptomatic while others may present with malaise, fatigue, loss of appetite, loss of weight, cloudy urine, fever, backache, flank pain, or abdominal discomfort. [symptoma.com]
Increased urination Unproductive attempts to urinate despite feelings of urgency General ill feelings Cloudy urine Abnormally colored urine Blood in the urine Foul smelling urine If you experience any of these sudden onset symptoms, please seek medical [my.clevelandclinic.org]
However, common symptoms include the following: a fever of more than 102 degrees abdominal, back, side, or groin pain painful or burning urination cloudy urine pus or blood in urine urgent and/or frequent urination fishy-smelling urine Other symptoms [cmc.ph]
[…] or lower back Thick or cloudy urine – it may contain blood As the infection progresses, you may experience: Fever Pain in the lower flank, part of the back where your kidneys are located Nausea and vomiting Fatigue Seniors may not show any of these signs [sepsis.org]
Common symptoms include: a fever greater than 102°F (38.9°C) pain in the abdomen, back, side, or groin painful or burning urination cloudy urine pus or blood in the urine urgent or frequent urination fishy-smelling urine Other symptoms can include: shaking [healthline.com]
- Nocturia
Suggestive symptoms : kidney pain (back pain), micturition disorders with polyuria (urinating more) and nocturia (urinating at night) and occasional appearances of polaki-disuria, pain during urination, pyuria (urine with pus). [bendomd.com]
Other symptoms of pyelonephritis would include: Dysuria Polyuria Nocturia Hematuria or pyuria Foul-smelling urine Renal colic (if due to presence of stones) Uncontrollable shivering Nausea and vomiting Diarrhea Hypotension (if sepsis has occurred) Poor [allhealthsite.com]
A diagnosis of CRF is supported by a history of nephrotic or nephritic syndrome long-standing nocturia renal osteodystrophy renal anemia bilaterally small kidneys increased echogenicity on renal ultrasonography Acute-on-chronic renal failure is a common [meddean.luc.edu]
[…] needle biopsy針生検 neobladder 新膀胱 nephrectomy腎摘出[術]、腎摘、腎切除[術] nephritis腎炎 nephrolithiasis腎結石 nephrology腎臓病学 nephropathy腎症 nephrostomy 腎瘻造設術 nephrotic syndromeネフローゼ症候群 nephrotoxicity腎毒性 neurogenic神経[原]性の neurogenic bladder 神経因性膀胱 neuropathic bladder 神経因性膀胱 nocturia [tokyo-med.ac.jp]
Reflux nephropathy Congenital vesicoureteral reflux Posterior urethral valves Acetaminophen (Paracetamol)overdose Urolithiasis ANSWER CASE NUMBER 12 [ImageScope] [WebScope] Clinical History: A 65-year-old woman had experienced increasing malaise with nocturia [web.duke.edu]
Workup
The diagnosis of CP can be difficult due to its variable and often vague clinical presentation. It can be suspected in patients who provide a history of renal calculi, recurrent UTIs, acute pyelonephritis or VUR. Occasionally the diagnosis is suspected based on incidental radiological findings or in patients presenting with hypertension. Laboratory tests like a complete blood count may reveal normochromic, normocytic anemia with leukocytosis. C-reactive protein (CRP) may be elevated in severe CP [9]. Urinalysis is likely to show hematuria, proteinuria, leukocytes with occasional epithelial cells, and rarely WBC casts. The severity of renal dysfunction can be estimated by renal function tests like serum creatinine, blood urea nitrogen, and estimated glomerular filtration rate [10]. Depending on the extent of renal damage there will be electrolyte imbalances like hyperkalemia, hyponatremia, and acidosis. Renal imaging is performed to detect the etiology of CP. Currently, magnetic resonance imaging (MRI) and computed tomography (CT) provide detailed information and are preferred over older modalities like plain X-rays, urography, and Tc-99m-DMSA nuclear scintigraphy, as well as histology [11]. In children, an ultrasound and a cystourethrogram are performed to exclude VUR [12].
Xanthogranulomatous pyelonephritis (XGP): Proteus, and less commonly Escherichia coli, Klebsiella, and Staphylococcus aureus, are found in urine cultures. Imaging studies like CT and MRI may detect a renal mass resembling a tumor [13]. However, the final diagnosis of XGP is based on histology of the nephrectomy specimen [13] [14].
Emphysematous pyelonephritis (EPN): Laboratory tests can show leukocytosis with elevated CRP [15], elevated blood glucose, and HbA1C levels. Blood and urine cultures may grow Escherichia coli, Klebsiella, or Proteus species. Gas may be noticed within the renal parenchyma on plain X-rays and ultrasound, while CT or MRI scans are useful in diagnosing the disease extent. [1] [16] [17] .
X-Ray
- Nephrolithiasis
Our observations indicate that autoimmune responses to THP may occur after exposure to THP by intravenous challenge in rabbits, by urinary reflux in pigs, and in recurrent nephrolithiasis in man. [ncbi.nlm.nih.gov]
Xanthogranulomatous Pyelonephritis This is an uncommon inflammatory state due to the constant obstruction in the kidneys because of nephrolithiasis (usually staghorn calculus) and would result to irreparable damage of the renal parenchyma. [allhealthsite.com]
Other Risk Factors: Diabetes mellitus, nephrolithiasis, chronic catheterization. [urology-textbook.com]
- Small Kidney
Pathology of Chronic Pyelonephritis Small kidney with a nodular surface and cicatricial retractions Lost demarcation of cortex and medulla in affected areas of the kidney. Initial renal scars are frequently found at the poles. [urology-textbook.com]
Imaging : Renal ultrasound may show small kidneys with a thin cortex. Intravenous pyelogram (IVP) may show small kidneys, ureteric and caliceal dilatation/blunting with cortical scarring. [patient.info]
Back to the top of the page "Small kidneys#" Unfortunately it is still not uncommon for patients to present with chronic kidney failure and usually hypertension - when the kidneys are scanned they are small. [kidneypatientguide.org.uk]
A diagnosis of CRF is supported by a history of nephrotic or nephritic syndrome long-standing nocturia renal osteodystrophy renal anemia bilaterally small kidneys increased echogenicity on renal ultrasonography Acute-on-chronic renal failure is a common [meddean.luc.edu]
We ought to note that while dilatations of the urinary tract are easy to detect in the prenatal period, it is common for small kidneys (renal hypoplasia) to go unnoticed in ultrasound examinations during pregnancy. [analesdepediatria.org]
- Bilateral Small Kidneys
A diagnosis of CRF is supported by a history of nephrotic or nephritic syndrome long-standing nocturia renal osteodystrophy renal anemia bilaterally small kidneys increased echogenicity on renal ultrasonography Acute-on-chronic renal failure is a common [meddean.luc.edu]
Urine
- Pyuria
Chronic Pyelonephritis may come to attention during an episode of acute pyelonephritis with its attendant constitutional symptoms, flank pain, bacteruria, and pyuria. [pathwaymedicine.org]
Suggestive symptoms : kidney pain (back pain), micturition disorders with polyuria (urinating more) and nocturia (urinating at night) and occasional appearances of polaki-disuria, pain during urination, pyuria (urine with pus). [bendomd.com]
Pyelonephritis is a sporadic, subacute to chronic disorder and the diagnosis is based on urinary symptoms (pyuria, haematuria, bacteriuria). [agris.fao.org]
[…] unilateral, may be bilateral) Dysuria as well as other symptoms of cystitis (e.g., frequency, urgency) Weakness, nausea, vomiting (diarrhea may also be present) Possible abdominal or pelvic pain References:[3] Diagnostics Laboratory tests Urinalysis Pyuria [amboss.com]
Diagnosis & Laboratory Investigations of Kidney Infection Blood and Urine Examination in Pyelonephritis Acute pyelonephritis classically shows the presence of WBC casts, hematuria along with pyuria and bacteriuria. [lecturio.com]
Serum
- Abnormal Renal Function
Before birth, at 20 weeks of gestation, foetal urine already amounts to more than 90% of the total volume of amniotic fluid, so the finding of oligohydramnios past this gestational age is an excellent indicator of abnormal renal function in the foetus [analesdepediatria.org]
Treatment
[…] need urgent operational treatment. [infomeds.net]
The results of carindacillin treatment, as judged by bacteriological evaluation 1 month post-treatment, were good in 12 (32%) and moderate in 9 of the patients. [ncbi.nlm.nih.gov]
Prognosis
Prognosis of Kidney Infection Acute uncomplicated pyelonephritis has an excellent prognosis and complete recovery is seen. Emphysematous pyelonephritis in diabetics shows very poor prognosis irrespective of the treatment. [lecturio.com]
The disease in most patients with unilateral disease runs a benign course; a poorer prognosis is associated with bilateral disease, hypertension and proteinuria. [ncbi.nlm.nih.gov]
Prognosis for chronic pyelonephritis Chronic pyelonephritis is diagnosed in 4 out of 1,000 asymptomatic adults. In children with urinary tract infections, prevalence of chronic pyelonephritis is as much as 40% to 50%. [ic.steadyhealth.com]
Prognosis The Birmingham Reflux Study clearly showed that medical and surgical management are equally effective in preventing renal damage from VUR. [8] Almost all children should receive a trial of medical management. [emedicine.medscape.com]
Differential Diagnoses and Treatment Syphilis — Types, Diagnosis and Treatment Chlamydia (Chlamydia Bacteria Infection) — Symptoms and Treatment Gonorrhea (The Clap) — Symptoms and Case Studies AIDS (Human Immunodeficiency Virus, HIV) — Etiology, Stages and Prognosis [play.google.com]
Etiology
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. [icd10coded.com]
In considering glomerular sclerosis, it is significant that loss of UEA-I binding and alpha 1AT deposition are common to both CPN and CDPGN, although their original etiologies are quite different. [ncbi.nlm.nih.gov]
[…] and pathogenesis of the following: Distinguish between leukemia and leukemoid reaction on the basis of: etiology pathogenesis laboratory data Morphologically differentiate a blast from a monocyte and lymphocyte. [web.duke.edu]
Renal imaging is performed to detect the etiology of CP. [symptoma.com]
Subsequently, opinions about the relative etiologic importance of pyelonephritis in hypertension have ranged FULL TEXT [annals.org]
Epidemiology
Epidemiology In the United States, VUR may be present in 30-40% of children with UTIs. [emedicine.medscape.com]
Symptoms and Case Studies AIDS (Human Immunodeficiency Virus, HIV) — Etiology, Stages and Prognosis Flu (Influenza) — Symptoms and Treatment Enteric Fever (Typhoid Fever) — Definition and Diagnosis Genital Herpes — Symptoms and Treatment Viral Hepatitis — Epidemiology [play.google.com]
Epidemiology of chronic pyelonephritis The proportion of chronic pyelonephritis as a cause of end-stage renal disease in children is up to 20%, but it has a declining tendency. [urology-textbook.com]
Epidemiology Incidence Community-acquired acute pyelonephritis: 28/10,000/year Prevalence Adult cases: 250,000/year, with 200,000 hospitalizations Etiology and Pathophysiology Escherichia coli (>80%) Other gram-negative pathogens: Proteus, Klebsiella, [unboundmedicine.com]
Pathophysiology
Etiology and Pathophysiology Chronic pyelonephritis is associated with progressive renal scarring, which can lead to end-stage renal disease (ESRD). [emedicine.medscape.com]
Pathophysiology of Chronic Pyelonephritis Ask-Upmark Kidney: The Ask-Upmark kidney is a special form of chronic pyelonephritis with an activated renin-angiotensin-aldosterone system (RAAS). [urology-textbook.com]
Epidemiology Incidence Community-acquired acute pyelonephritis: 28/10,000/year Prevalence Adult cases: 250,000/year, with 200,000 hospitalizations Etiology and Pathophysiology Escherichia coli (>80%) Other gram-negative pathogens: Proteus, Klebsiella, [unboundmedicine.com]
Pathophysiology. Jones & Bartlett Learning, 2002; pp. 222-245. Jennette JC. The Kidney. In: Rubin E, Reisner HM. Essentials of Rubin's Pathology. Lippincott Williams & Wilkins, 2009; pp. 350-374. [news-medical.net]
Prevention
To prevent the development of a severe syndrome, such as renal failure, treatment and prevention of diseases of the urinary system should be carried out on time, preventing the development of subsequent complications. [acikgunluk.net]
Bacteriae usually attack the lower parts of the tract, as urine leak prevents the spreading of infection by the tract. [healthy-inside.com]
U may require surgery to correct hydronephrosis & facilitate urinary drainage to prevent urinary stagnation which predispose to stones. [healthtap.com]
Treatment options usually include antibiotic medications to treat the infection and may involve surgery to correct an anatomical problem and prevent future infections, as well as other complications. [wisegeek.com]
Can You Prevent Kidney Infections? Prevention of urinary tract and kidney infection primarily focuses on reducing the associated risk factors. [emedicinehealth.com]
References
- Huang JJ, Tseng CC. Emphysematous pyelonephritis: clinicoradiological classification, management, prognosis, and pathogenesis. Arch Intern Med. 2000;160:797-805.
- Vachvanichsanong P. Urinary tract infection: one lingering effect of childhood kidney diseases - review of the literature. J Nephrol. 2007;20:21-28.
- Marra G, Oppezzo C, Ardissino G, et al. Severe vesicoureteral reflux and chronic renal failure: a condition peculiar to male gender? Data from the ItalKid Project. J Pediatr. 2004;144:677-681
- Wennerstrom M, Hansson S, Jodal U, et al. Primary and acquired renal scarring in boys and girls with urinary tract infection. J Pediatr. 2000;136:30-34.
- Moreau JF, Grenier P, Grunfeld JP, et al. Renal clubbing and scarring in adults: a retrospective study of 110 cases. Urol Radiol. 1979-1980;1:129-136
- Guignard JP. Importance of vesicoureteral reflux in the pathogenesis of chronic pyelonephritis [in French]. Schweiz Med Wochenschr. 1983;113:223-228
- Grainger RG, Longstaff AJ, Parsons MA. Xanthogranulomatous pyelonephritis: a reappraisal. Lancet. 1982;1:1398-1401
- Rubenstein JN, Schaeffer AJ. Managing complicated urinary tract infections: the urologic view. Infect Dis Clin North Am. 2003;17:333-351.
- Yang WJ, Cho IR, Seong-do H, et al. Clinical implication of serum C-reactive protein in patients with uncomplicated acute pyelonephritis as marker of prolonged hospitalization and recurrence. Urology. 2009;73:19-22.
- Stevens LA, Coresh J, Feldman HI, et al. Evaluation of the modification of diet in renal disease study equation in a large diverse population. J Am Soc Nephrol. 2007;18:2749-2757.
- Kljucevsek D, Kljucevsek T, Kersnik LT, et al. Catheter-free methods for vesicoureteric reflux detection: our experience and a critical appraisal of existing data. Pediatr Nephrol. 2010;25:1201-1206.
- Riccabona M, Fotter R. Urinary tract infection in infants and children: an update with special regard to the changing role of reflux. Eur Radiol. 2004; 14: L78-L88.
- Loffroy R, Guiu B, Wafta J, et al. Xanthogranulomatous pyelonephritis in adults: clinical and radiological findings in diffuse and focal forms. Clin Radiol. 2007;62:884-890.
- Dwivedi US, Goyal NK, Saxena V, et al. Xanthogranulomatous pyelonephritis: our experience with review of published reports. ANZ J Surg. 2006;76:1007-1009
- Kondo T, Okuda H, Suzuki M, et al. A case of emphysematous pyelonephritis improved with conservative therapy - indication for conservative therapy. Hinyokika Kiyo. 2000;46:335-338.
- Evanoff GV, Thompson CS, Foley R, et al. Spectrum of gas within the kidney. Emphysematous pyelonephritis and emphysematous pyelitis. Am J Med. 1987;83:149-154.
- Vourganti S, Agarwal PK, Bodner DR, et al. Ultrasonographic evaluation of renal infections. Radiol Clin North Am. 2006;44:763-775