Page 729 - TNFlipTest

Toronto Notes 2019 Parenchymal Kidney Diseases
Signs and Symptoms
• severe/refractoryHTNand/orhypertensivecrises,withnegativefamilyhistoryofHTN • asymmetricrenalsize
• epigastricorflankbruits
• spontaneoushypokalemia(reninactivationinunder-perfusedkidney)
• increasingCrwithACEI/ARB
• flashpulmonaryedemawithnormalLVfunction
Investigations
• mustestablishpresenceofrenalarterystenosisandproveitisresponsibleforrenaldysfunction
• duplexDopplerU/S(kidneysize,bloodflow):goodscreeningtest(operatordependent)
• digitalsubtractionangiography(riskofcontrastnephropathy)
• CTorMRangiography(effectivenoninvasiveteststoestablishpresenceofstenosis,forMRavoid
gadolinium contrast if eGFR <30 mL/min because of risk of systemic dermal fibrosis) • ACEIrenography(e.g.captoprilrenalscan)
• renalarteriography(goldstandard)
Treatment
• surgical:percutaneousangioplasty±stent,surgicalrevascularization,occasionallysurgicalbypass
• medical:BPloweringmedications(ACEIisdrugofchoiceifunilateralrenalarterydiseasebut
contraindicated if bilateral renal artery disease)
• littleornobenefitiftherapyislate(e.g.kidneyisalreadyshrunken),however,therapycanbe
considered to save the opposite kidney if normal
3 . RENAL VEIN THROMBOSIS
Etiology
• hypercoagulablestates(e.g.nephroticsyndrome,especiallymembranous),ECFvolumedepletion, extrinsic compression of renal vein, significant trauma, malignancy (e.g. RCC), sickle cell disease
• clinicalpresentationdeterminedbyrapidityofocclusionandformationofcollateralcirculation
Signs and Symptoms
• acute:N/V,flankpain,hematuria,elevatedplasmaLDH,±riseinCr,suddenriseinproteinuria • chronic:PE(typicalfirstpresentingsymptom),increasingproteinuriaand/ortubuledysfunction
Investigations
• renalvenography(goldstandard),CTorMRangiography,duplexDopplerU/S
Treatment
• thrombolytictherapy±percutaneousthrombectomyforacuterenalveinthrombosis
• anticoagulationwithheparinthenwarfarin(1yrorindefinitely,dependingonriskfactors)
MEDIUM VESSEL DISEASE 1 . KAWASAKI DISEASE
• see Pediatrics, P86
2 . POLYARTERITIS NODOSA
• seeRheumatology,RH19
• kidneysmostcommonlyinvolvedorgan
• heterogenousimpactonrenalfunction
• pathologicallycancauseglomerularischemiawhichmanifestsasmildproteinuriaandhypertension
SMALL VESSEL DISEASE
1 . HYPERTENSIVE NEPHROSCLEROSIS
• seeHypertension,NP35
2 . ATHEROEMBOLIC RENAL DISEASE
• progressiverenalinsufficiencyduetoembolicobstructionofsmall-andmedium-sizedrenalvesselsby atheromatous emboli
• spontaneousorafterrenalarterymanipulation(surgery,angiography,percutaneousangioplasty)
• anticoagulantsandthrombolyticsinterferewithulceratedplaquehealingandcanworsendisease
• investigations
■ eosinophilia, eosinophiluria, and hypocomplementemia
■ renal biopsy: needle-shaped cholesterol clefts (due to tissue-processing artifacts) with surrounding
tissue reaction in small-/medium-sized vessels
Nephrology NP29
Stenting and Medical Therapy for Atherosclerotic Renal Artery Stenosis
NEJM 2014;370:13-22
Study: Multicentre, unblinded RCT, median follow- upof43mo.
Patients: 947 patients with atherosclerotic renal- artery stenosis who also have significant systolic HTN or CKD.
Intervention: Percutaneous revascularization (stenting) with medical therapy (statins, ARB, calcium channel blockers, HCTZ and BP control) versus medical therapy alone.
Outcomes: Occurrence of adverse CV or renal event (composite of death from CV or renal cause, MI, stroke, hospitalization for CHF, progressive renal insufficiency, or need for renal replacement therapy) and all-cause mortality.
Results: No significant difference in primary composite end point between participants who received stenting or those on medical therapy alone. No significant differences between the treatment groups in the rates of the individual components of the primary end point or in all-cause mortality. Conclusion: Renal artery stenting did not confer a significant benefit with respect to the prevention
of clinical events when added to comprehensive, multifactorial medical therapy in people with atherosclerotic renal artery stenosis and HTN
or CKD.