inflammatory diseases of the kidney part 2
TRANSCRIPT
Renal inflammatory diseases of the kidney Part 2
THORSANG CHAYOVAN
(Does not include pyelonephritis/pyonephrosis/pyelitis)
Xanthogranulomatous pyelonephritis
• Chronic destructive granulomatous disease
• Middle-aged women (age 40-60)
• Diabetes
• Symptoms: fever, flank pain, persistent bacteriuria, or history of recurrent infected nephrolithiasis
RadioGraphics 1991; 11:485-498 RadioGraphics 2000; 20:215-243
Pathophysiology of XGP
Long-standing partial obstruction
subacute bacterial infection
Incomplete immune response
Parenchymal destruction
Caliectasis (peripelvic fibrosis limits pelviectasis)
Deposition of lipid-laden macrophages (xanthoma cells)
Irreversible destruction of the renal parenchyma
Two forms of XGP
Diffuse/global (85%)
Localized/focal (15%)
Xanthogranulomatous pyelonephritis
Diffuse form of XGP
• Renal enlargement
• Calcifications filling the renal pelvis (often staghorn)
• Replacement of the renal parenchyma by dilated calyces and abscess (multiple wall-enhanced oval hypodensities)
• Cortical thinning
• Decreased contrast excretion
• Areas of fat attenuation = lipid-rich xanthomatous tissue
Radiol Clin N Am 50 (2012) 259–270
RadioGraphics 2008; 28:255–276
XanthogranulomatousPyelonephritis
• KUB• Exploded staghorn with large renal shadow
Infect Dis Clin North Am 2003 (Kawashima)
XanthogranulomatousPyelonephritis
• CT• “Bear Claw/paw”• Massive caliectasis
(without pelviectasis)• Parenchyma enhances• Stones
Infect Dis Clin North Am 2003 (Kawashima)
Focal form of XGP • DDx a renal tumor (RCC) “tumefactive/pseudotumoral”
RadioGraphics 2008; 28:255–276
Triad
• Nonfunctioning
• Renal enlargement • Caliectasis with less pelviectasis, parenchymal loss
• Stones (90%)• Staghorn
Complications of XGP
• Perinephric/psoas abscesses
• Fistulae (renocolic and renocutaneous)
Radiol Clin N Am 50 (2012) 259–270
Radiol Clin N Am 50 (2012) 259–270
RENAL TUBERCULOSIS
• The most common extrapulmonary site of TB
• Hematogenous spreading from lung
• 4% to 8% of pulmonary tuberculosis
• Ureteral and bladder involvement can occur via descending infection
Granulomas
immunocompetent host
(confined to the renal cortex)
Reactivationimmunocompromised host
(granulomas enlarge)
Capillary rupture
Medulla (along the loop of Henle and proximal tubules)
Proximal collecting system
Ureter
Bladder
Genital organs
Across retroperitoneal fascial planes
Tuberculous bacilli
periglomerular capillaries
Small abscesses
Radiol Clin N Am 50 (2012) 259–270
RENAL TUBERCULOSIS
• Insidious and asymptomatic• Renal involvement can be indolent for more than 20 years
• LUTS and/or back or flank pain
• Constitutional symptoms
• Diagnosis: • U/C
• Biopsy
Imaging of GU tuberculosis
• Depends on the stage of disease
• Progressive infection• Granuloma
• Caseous necrosis
• Cavitation
• Eventually destroy the kidney (autonephrectomy)
• The initial inoculation and granuloma formation• Not radiographically evident
RadioGraphics 2004; 24:251–256
TB: early in reactivation--acute inflammation
• Localized soft tissue edema and vasoconstriction focal hypoperfusion + striated nephrogram
• Papillary necrosis a moth-eaten calyx (on excretory urography or enhanced CT)
• Tuberculoma with central caseous necrosis
• Eventually rupture into the draining calyx renal pelvis
Striated nephrogram• acute obstruction
(ureteric/ tubular)• acute pyelonephritis• acute renal vein
thrombosis• acute renal contusion• acute post RT• acute tubular necrosis• hypotension
Radiol Clin N Am 50 (2012) 259–270
Case courtesy of Dr Mohammad Taghi Niknejad, Radiopaedia.org, rID: 21350
Courtesy of Dr. Annie Agarwal
Radiographics 2004: 24;issue suppl_1
https://www.med-ed.virginia.edu/courses/rad/gu/kidneys/analgesic.html
https://www.med-ed.virginia.edu/courses/rad/gu/kidneys/analgesic.html
Courtesy of Dr. Annie Agarwal
Rev Chil Radiol 2010; 16(3): 128-133
Radiographics 2004: 24;issue suppl_1
Radiol Clin N Am 50 (2012) 259–270
Papillary necrosis
AD SPORT C
A: analgesic abuse (phenacetin, NSAID's, paracetamol)D: diabetes mellitusS: sickle cell diseaseP: pyelonephritis (especially in children)O: obstructionR: renal vein thrombosis
T: renal tuberculosis (not usually confined to papillae)
C: cirrhosis
http://radiopaedia.org/articles/renal-papillary-necrosis-mnemonic
excretory phase reveals a hypodense parenchymal mass in the upper pole of left kidney with perinephric extension. Biopsy of the lesion revealed tubercular abscessRadiol Clin N Am 50 (2012) 259–270
Late renal TB infection
• Fibrotic reaction causing stenosis and stricture • Uneven caliectasis
• Obstruction
• Progressive renal dysfunction
• Incomplete opacification of the calyx (phantom calyx)
• Calcium deposition • Putty kidney--dystrophic calcifications involving the entire kidney
• Parenchymal atrophy
• Progressive hydronephrosis
• Autonephrectomy
RadioGraphics 2004: 24;issue suppl_1
Courtesy of Dr. Annie Agarwal
Courtesy of Dr. Annie Agarwal
Courtesy of Dr. Annie Agarwal
Putty kidney• Diffuse or scattered renal
calcifications (25%)
• Often small kidney
Radiographics 2004: 24;issue suppl_1
RadioGraphics 2008; 28:255–276
http://radiopaedia.org/articles/putty-kidney
Radiol Clin N Am 50 (2012) 259–270
TB ureteral and bladder spreading
• Ureteral involvement • Initially, mucosal irregularity “sawtooth” ureter ± Ureteral dilatation • Stricturing and ureteral shortening • Multiple strictures a long segment of narrowing• Multiple nonconfluent strictures “corkscrew” ureter• Calcification
• CT can also demonstrate periureteral fibrosis and ureteral wall thickening
• Urinary bladder involvement• Reduced bladder capacity • ± Bladder wall thickening and calcification
Courtesy of Dr. Annie Agarwal
Courtesy of Dr. Annie Agarwal
Courtesy of Dr. Annie Agarwal
Radiol Clin N Am 50 (2012) 259–270
Tuberculosis• CT Urography/IVP
• Renal• Moth eaten, fuzzy calyx with papillary
necrosis• Infundibular, pelvic fibrosis (purse
string pelvis)• Calyceal/pelvic obstruction
(hydrocalyx, phantom calyx)• Renal nonfunction (autonephrectomy),
scarring calcification (putty kidney)• Note: renal changes mimic TCC
• Ureter• Ulcerations and irregularity; sawtooth
(early)• Multiple strictures; corkscrew (later)• Short, strait, aperistaltic (latest)• Calcifications (DDX: schistosomiasis)
• Bladder involvement is very late
AJR 2005; 184:143-150
RENAL CALCIFICATIONSA. Dystrophic calcification due to localised disease:
Usually one kidney or part of one kidney. Infections :
1. Tuberculosis
2. Hydatid disease
3. Xanthogranulomatous pyelonephritis
4. Abscess
Carcinoma
Aneurysm of renal artery
Renal CalcificationsB. Nephrocalcinosis
Medullary : 1. Hyperparathyroidism
2. RTA
3. Medullary Sponge Kidney
4. Renal papillary necrosis
5. Causes of hypercalcemia or hypercalciuria
6. Preterm infants
7. Primary hyperoxaluria
Cortical :1. Acute cortical necrosis
2. Chronic glomerulonephritis
3. Chronic transplant rejection
UPPER TRACT FUNGAL INFECTION
• Hematogenous seeding or ascending urinary tract infection• With hematogenous dissemination, fungi are filtered by the glomerulus and
become lodged in the distal tubules
• Candida aibicans or Aspergillus species
• Predisposing factors: immunosuppression, prolonged antibiotic or steroid therapy, diabetes mellitus, and urinary obstruction
• Acute pyelonephritis
• May eventually develop multiple renal abscesses
• May develop fungus balls (mycetomas/urobezoars)• A conglomeration of inflammatory cells, fungus, necrotic or mucoid debris,
and a calculous matrix
UPPER TRACT FUNGAL INFECTION
• A striated nephrogram
• Multiple abscesses (multiple, small, hypodense collections)
• Fungus balls or mycetomas• Urography: radiolucent filling defects in the collecting system• US: echogenic masses in the renal collecting system that do not demonstrate
acoustic shadowing and can mimic blood clots or pyogenic debris • CT: a nonspecific irregularly marginated mass of soft tissue attenuation in the
collecting system• DDx other causes of intraluminal filling defects
• Blood clots • Sloughed papillae
RadioGraphics 1997; 17:851-866
Radiol Clin N Am 50 (2012) 259–270
RENAL ASPERGILLOSIS
• Renal aspergillosis has been described to appear as a complex cystic lesion/abscess
Radiol Clin N Am 50 (2012) 259–270
UPPER TRACT FUNGAL INFECTION
• Antifungal therapy
• Unilateral: nephrectomy/percutaneous drainage
• Bilateral: local irrigation with amphotericin B
Post-radiation injury of the kidney
POST RADIATION
• Very radiosensitive organ• VS ureters--fairly resistant to radiation-induced changes (smoothly tapering)
• Radiation oncologists aim doses of 20 Gy+
• 28 Gy- to both kidneys in 5 weeks frequently leads to renal failure
• Low doses such as 10 Gy may be associated with a subsequent diffuse or focal parenchymal loss • 5% volume loss ↔ 20% renal function decline
POST RADIATION
• Acute radiation nephritis• Normal in size and shape
• Glomerular damage histologically
• Radiological changes appear months to years after treatment• Atrophic poorly functioning but non-obstructed kidneys with smooth outlines
• Compensatory hypertrophy of the non-irradiated contralateral kidney
• Portion affected according to portal
• DDx pyelonephritis, renal infarction, and, rarely, renal masses
RadioGraphics 2013; 33:599–619
RadioGraphics 2013; 33:599–619
Cancer Imaging. 2006; 6(Spec No A): S131–S139.
RENAL MALAKOPLAKIA
RENAL MALAKOPLAKIA
• A rare chronic inflammatory process
• Associated with E coli urinary tract collecting system infection (most commonly the urinary bladder)
• Isolated renal involvement is rare
• Middle-aged women with chronic urinary tract infections or in immunocompromised host• A peaks in the fifth decade of life, but occasionally occurs in children
• Symptoms of urinary tract infection/renal failure in advanced disease
Pathogenesis of malakoplakia
• Abnormal macrophage function
• These partially digested bacteria persist and form intracellular inclusion bodies (Michaelis-Gutmann bodies) in large eosinophilic macrophages (Hansemann histiocytes)
• Formation of tumorlike lesions with the macrophage
• Occasionally seen outside the genitourinary tract, including in the gastrointestinal tract and skin
RadioGraphics 2008; 28:255–276
RENAL MALAKOPLAKIA
• 75% multifocal diffusely enlarged kidney • Unilateral > bilateral• Imaging
• An enlarged kidney, a low-attenuation mass, or a diffuse infiltrative disease.• US: a diffusely enlarged kidney, poorly defined hypoechoic masses, and distortion of
the renal architecture• CT:
• Multiple hypoenhancing masses that can range in size and eventually coalesce to form larger masses
• A mass; DDx renal cell carcinoma• MR: multiple 1–2-cm nodules with low signal intensity on T1- and T2-weighted
images and delayed enhancement of intervening fibrous stroma
• Biopsy or surgery is required to make the diagnosis
RadioGraphics 2008; 28:255–276
• Findings:
• Bilateralor unilateral
• Focal, multifocal or diffuse
• infiltrating masses
• ± Renal pelvis involvement
• Uncommon calcifications
Radiographics. 2000;20:215-243
RENAL MALAKOPLAKIA
References
• http://www.ncbi.nlm.nih.gov/pubmed/22498442
• http://pubs.rsna.org/doi/full/10.1148/rg.241035071
• http://pubs.rsna.org/doi/pdf/10.1148/radiographics.20.1.g00ja08215
• http://pubs.rsna.org/doi/full/10.1148/rg.332125119
• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1805064/
• Please see each pictures in the slides.
Pictorial resources