1.14 Non-specific infections of the kidney parenchyma and of the capsules Flashcards
Non-specific infections of the kidney parenchyma and of the capsules- list
Acute uncomplicated pyelonephritis
Acute complicated pyelonephritis
*Chronic pyelonephritis
*Xanthogranulomatous pyelonephritis
*Papillary necrosis
*Emphysematous pyelonephritis
*Pyonephrosis
urosepsis
Pyelonephritis def
An infection of the parenchyma and the collecting system of the kidney, most
often occurring as a result of an ascending infection
Acute uncomplicated pyelonephritis More common in
women
Acute uncomplicated pyelonephritis
Symptoms
o chills
o Flank or back pain
o Fever
o Vomiting and nausea
o Fatigue
o Painful urination
o Increased frequency
o Nocturia
o Cloudy or abnormal urine color
o Mental changes, confusion
Acute uncomplicated pyelonephritis- diagnosis
o Based on history, PE, laboratory and imaging tests
o Laboratory tests
* Urinalysis: WBC, RBC, bacteria in urine
* 100 000 bacteria count
* Identify causative organism: E. coli, klebsiella, Enterobacter, proteus,
pseudomonas
o Blood analysis: CRP, WBC, ESR, PCT
o Radiographic
* US to rule out concurrent obstruction
* Contrast enhanced CT: confirms the diagnosis.
Perfusion defect, parenchyma enlargement.
Acute uncomplicated pyelonephritis- treatment
o Resolve in 2-3 weeks with antibiotics, first few days IV
* Augmentin
* 3rd generation cephalosporins
* fluoroquinolone
supportive
Acute complicated pyelonephritis- definition
- Structural or functional abnormalities in UT (obstruction)
- Anatomical anomaly (VUR, calycomegalia, ureteral stricture), cancer, stone
- Metabolic abnormalities predisposing to UTI: DM, immune deficiency, pregnancy
- unusual pathogens
- recent UT instrumentation
- Recent AB use
Pathogenesis- Acute complicated pyelonephritis
Obstruction in the upper UT
Acute complicated pyelonephritis- Symptoms
Severe general symptoms:
* High fever,
* fatigue, shaking,
* chills
* nausea
* vomiting,
* abdominal pain
* flank pain
* dry tongue
Acute complicated pyelonephritis- diagnosis
o Laboratory tests
* Urinary sediment: WBC, casts, RBC
* urine culture
* Blood tests: CRP, ESR, WBC etc.
o Imaging
* US can show potential abscess and size of kidney and collecting system
* CT, contrast enhanced CT
* excretory urography
* DMSA
Acute complicated pyelonephritis- Treatment
o Remove complicating factors
o Hospitalization
* first few days IV antibiotics
* supportive
o Drainage!!!!!
Chronic pyelonephritis Definition
Chronic pyelonephritis is characterized by renal inflammation and scarring induced by :
* recurrent or persistent renal infection,
* vesicoureteral reflux,
* or other causes of urinary tract obstruction.
It occurs almost exclusively in patients with major anatomic anomalies , most commonly young children with vesicoureteral reflux (VUR).
o Reflux nephropathy: Association with a small, clubbed scarred, kidney with VUR
Chronic pyelonephritis pathogenesis
o Hematogenous or ascending
o Incomplete treated acute pyelonephritis > scarring and atrophy > slow
progression into chronic state
Chronic pyelonephritis predisposing factors
o Urinary obstruction
o Pregnancy
o Metabolic disease
o Iatrogenic cause
o Generalized and local lack of resistance
Chronic pyelonephritis symptoms
o Asymptomatic in many
o Pregnant present with UTI often
o Complication of chronic azotemia: Hypertension, visual impairment, headache,
fatigue, polyuria, polydipsia
Chronic pyelonephritis Diagnosis
o Radiological and pathological examination
o Urinalysis: Leukocytosis, RBC, proteinuria
o Increased creatinine
o Radiographic imaging
* US: Small atrophic kidneys on affected side, calyceal dilatation, cortical
scarring
* IV urogram: Small atrophic kidney, renal scarring with clubbing of underlying calyx, poles are commonly affected
* Radioisotope studies
Chronic pyelonephritis Treatment
o Limited since damage is irreversible
o Eliminating recurrent UTI and VUR, obstruction or stones
o Long-term antibiotics
o Surgical removal of affected kidney to prevent complications
o Kidney transplant or dialysis if chronic failure develops
Complication of chronic azotemia in chronic pyeloneph
Hypertension,
visual impairment,
headache,
fatigue,
polyuria, polydipsia
Xanthogranulomatous pyelonephritis- definition
Rare, severe, chronic, diffuse destructive parenchymal inflammatory disorder
o Unilateral mostly, resulting in non-functioning enlarged kidney with obstructive
uropathy secondary to stone
retroperitoneal involvement in Xanthogranulomatous pyelonephritis (3)
- Kidney alone
- Kidney and perinephric fat
- Kidney, perinephric fat and extensive retroperitoneum
Xanthogranulomatous pyelonephritis- pathogenesis
o Unknown
o Primary factors needed
* Obstruction
* UTI
* Nephrolithiasis
o Proposed: Obstruction > infection > tissue destruction and collection of lipid
material by histiocytes.
Lipid-laden macrophages are distributed around the
parenchymal abscesses and calyces.
Fibrous tissue reaction form granulomatous process initially, that infiltrates and replaces renal parenchyma
Xanthogranulomatous pyelonephritis- symptom
o Flank pain, fever, chills, bacteriuria
o Flank mass
Xanthogranulomatous pyelonephritis- diagnosis
o Laboratory: Urine culture showing E. coli or proteus
o Blood test
o Imaging: CT
Xanthogranulomatous pyelonephritis- treatment
Nephrectomy
Papillary necrosis
- Definition
o Renal papillary necrosis is characterized by coagulative necrosis of the renal
medullary pyramids and papillae brought on by several conditions and toxins that
produce ischemia
Papillary necrosis
- etiologies
o Analgesic agents
o Localized, diffuse, unilateral, bilateral
* DM,
* UTI,
* hemoglobinopathies,
* renal vein hypotension,
* liver cirrhosis
Papillary necrosis- symptoms
o Related to UTI: Recurrent fever, malaise, dysuria, flank pain, proteinuria, hematuria, leukocytosis
o Passage of sloughed papillae can cause renal colic, ureteric obstruction and
urinoma= a collection of urine that forms in the back of your abdomen.
o Can present with acute oliguric renal failure (<400ml/day)
Papillary necrosis Diagnosis
o Laboratory
o Imaging:
* IV urogram will show papillary necrosis with scarring of parenchyma
Papillary necrosis treatment
Antibiotics and treat underlying disease
Emphysematous pyelonephritis
- Definition
A life-threatening, fulminant, necrotizing upper UTI associated with gas within the
kidney and perinephric space
Emphysematous pyelonephritis pathogenesis
o Acute and chronic necrotizing pyelonephritis with multiple renal abscesses
o Mixed acid fermentation of glucose by Enterobacteriaceae
o DM, obstructive uropathy, urinary calculi, calyceal stenosis, neoplasm are
predisposing
Emphysematous pyelonephritis symptoms
o Chills, fever, flank pain, lethargy, confusion
o Septic shock
o Crepitant mass
Emphysematous pyelonephritis diagnosis
o Laboratory: Bacteriuria, positive urine culture
o Imaging
* Plain radiography depicting air
* CT
Emphysematous pyelonephritis treatment
o Early diagnosis and aggressive administration of antibiotics can give recovery
o Percutaneous nephrostomy
o Immediate surgery
Pyonephrosis
- Definition
Pyonephrosis refers to infected purulent urine in obstructed collecting system
Pyonephrosis pathogenesis
Pyonephrosis can be seen as a complication of acute pyelonephritis, usually seen with complete or incomplete obstruction of tubules
Pyonephrosis symptoms
From asymptomatic to septic
Pyonephrosis imaging
o Renal US
Show one of four patterns
1. Persistent echoes from the inferior portion of the collecting system
2. Fluid-debris level with dependent echoes that shift when the patient
changes position
3. Strong echoes with acoustic shadowing from air in the collecting
system
4. Weak echoes throughout dilated collecting system
Pyonephrosis treatment
o Antibacterial drugs and drainage
o Consider nephrostomy placement
o Nephrectomy if kidney is malfunctioning
