Nephrology Flashcards

Question

Renovascular HTN- who to screen and How

Answer 1

Who to screen – Patients presenting with 2 or more of the following * Sudden onset or worsening HTN age >55 or <30 * Abdominal bruit * HTN resistant to ≥ 3 drugs * Increase in Cr ≥ 30% with ACEi or ARB * Other atherosclerotic vascular disease, particularly in smokers or dyslipidemia * Recurrent pulm edema associated w/ Hypertension emergency * How to Screen – Any of: Renal Doppler US, captopril renogram, MRA, CTA * Avoid captopril and CTA if renal GFR <60 ml/min/1.73m2 ACEi or ARB not contraindicated with bilateral renal artery stenosis Atherosclerotic RAS is managed medically – no benefit to stenting over medical therapy in most * Angioplasty and stenting could be considered if any of the following present: (REVISED in 2020 guidelines) 1. uncontrolled HTN resistant to maximally tolerated pharmacotherapy 2. progressive renal function decline 3. Acute pulmonary edema

Answer 2

Paroxysmal, unexplained, labile, and/or severe (≥ 180/110) sustained HTN refractory to usual therapy – HTN + symptoms of catecholamine excess (headaches, palpitations, sweating, flushing) – HTN triggered by beta-blockers, MAO-Is, surgery, anesthesia, micturition – Incidental adrenal adenoma – Hereditary causes– such as Von-Hippel-Lindau, MEN 2A or 2B, neurofibomatosis type 1 How to Screen – Biochemical screening test first – YES ✓ – 24hr urine total metanephrines and catecholamines (and Creatinine to ensure adequate collection) – MAYBE – Plasma free metanephrines and free normetanephrines may also be considered – NOT ❌ urinary VMA

Answer 3

Work up for FMD if Htn and one of more: (CHEP 2020) – Kidneys asymmetrical (>1.5cm difference) – Abdominal bruit but no atherosclerosis risk factors – Confirmed FMD in another vascular bed – Family hx of FMD * How to workup for FMD: – CTA or MRA * Once FMD is confirmed: – Screen vasculature from head to pelvis with either CTA or MRA (cervicocephalic lesions, intracranial aneurysms, lesions in other vascular beds)

Answer 4

Elevated BP + evidence of end organ damage – Pulmonary edema, cardiac ischemia, neurologic deficits, acute renal failure, aortic dissection, and eclampsia Treatment: 1) Admit to Step down/ICU level of care for continuous BP monitoring 2) Lower BP by 20-25% only within first 1-2 hours * Lower the blood pressure by 25% in 1-2 hours and then to 160/100 over the next 2-6 hours, and then gradually to normal over few days * Certain conditions (ie. Aortic dissection, eclampsia) may require rapid control of BP whereas other conditions (ie stroke) require even slower lowering of BP (<15% lowering) 3) Use of IV medications to lower BP (rapid acting and easily titratable) * Oral meds may have delayed GI absorption and can suddenly tank BP if they’re all absorbed at a later time 4) IV med options: IV labetalol, esmolol, nicardipine, hydralazine, nitroglycerin 5) Transition to PO medications and transfer to wards 6) Consider work up of secondary hypertension

Answer 5

AIN or pyelonephritis= WBC casts ATN=Muddy brown casts Glomerular disease: -Nephritic- RBC casts & dysmorphic RBC -Nephrotic-Oval fat bodies or fatty casts

Answer 6

Fulminant disease, limited to lung and kidney – Called Goodpasture’s if RPGN is accompanied by pulmonary hemorrhage * Treatment: – Pulse corticosteroids – Cyclophosphamide – Plasma exchange (until titers are no longer detectable) EXCEPTIONS: consider conservative treatment if 85-100% crescents, no pulm hemorrhage, treated w/dialysis at presentation [where risk of immunosuppression potentially outweigh benefits as pt has ESRD already] * Steroids usually 6 months/ Cyclophosphamide 2-3 months * No maintenance therapy!

Answer 7

Microscopic Polyangiitis (MPA) Granulomatosis with polyangiitis (GPA) Eosinophilic granulomatosis with polyangiitis (EGPA) Clinical features: – Constitutional symptoms – Arthralgias, rash – Sinusitis, asthma, pulmonary hemorrhage – Nephritis – Mononeuritis multiplex

Answer 8

INDUCTION: Methylprednisolone up to 1g x 3 days + Cyclophosphamide or Rituximab *RPGN, Creat > 354 à Cyclophosphamide preferred* (KDIGO 2021 – less data for Ritux) *When to consider Ritux over Cyclophosphamide: – Pre-menopausal women, men interested in preserving fertility – Frail older adults – Relapsed disease – ACR (Rheum) 2021 guidelines: Rituximab preferred (if no evidence of RPGN) Maintenance therapy - Azathioprine OR continue Rituximab if used as induction agent - Taper glucocorticoids (usually 1mg/kg/d first week then taper) No maintenance therapy in dialysis dependent pts x 3 months with no extra-renal manifestations When to use plasma exchange (PLEX): Anti-GBM+ (“double positive”/overlap) Also consider PLEX: KDIGO: If ANCA+ GN vital organ / life threatening, Creat > 500 ACR: Patients at ↑ risk of progression to ESRD (accept a potential ↑ risk of infection)

Answer 9

Low C3: Post-streptococcal/infectious GN – 2–3 weeks post-infection (strep throat/strep cellulitis, chronic abscess, endocarditis, etc) Presentation varies from * Microscopic hematuria to * Proliferative GN: red/ brown urine, proteinuria, edema, Htn, AKI – Diagnosis: low C3, normal C4, +ASOT (70%), +anti-DNase B (90%) – Management: supportive care (this can include diuresis if edema); treat infection if still active (e.g. cultured from any site) – Resolves in 3 – 4 weeks – Biopsy only if considering other glomerular disorders, or course varies from typical trajectory i.e. severe AKI requiring dialysis: this is uncommon with PSGN

Answer 10

Low C4: MPGN Multiple etiologies: – Associated with HCV (>HBV), HIV, cryos, other infection (endocarditis, Syphilis, endemic parasites – malaria, schistosoma), complement dysregulation (there is genetic testing for this, beyond scope of GIM), monoclonal gammopathies, autoimmune disorders, TMA/ HUS, APLAS, Sickle Cell anemia, Polycythemia – Nephritic syndrome with low C4, normal C3 (*but can be low too) – Dx on biopsy – Management: treat the underlying cause

Answer 11

All patients with CKD should be screened for Hep C at diagnosis of CKD, and at time of initiation of renal replacement therapy * All patients should be evaluated for HCV Therapy (if transplant candidate, coordinate timing w transplant centre) – Both pangenotypic regimens in your GI lecture can be even in CKD 5 * HCV + GN workup – Note management nuances outside of scope of GIM... but FYI if RPGN or cryoglobulinemic flare KDIGO suggests Antiviral AND immunosuppression (Ritux) +/- PLEX * Or if patient has progressive GN or cryoglobulinemic kidney disease not responding to antivirals “I would consult my colleagues in nephrology / hepatology / infectious diseases / heme...”

Answer 12

SLE most common (more in Rheum lecture) Presents as nephritic and/or nephrotic. Elevated dsDNA. Dx. - requires Biopsy Treatment Principles: Hydroxychloroquine for all Often young women – remember pregnancy test and counseling before starting immunosuppression (particularly MMF/cyclophosphamide!) Class III/IV: induction with steroids and 1 of cyclophosphamide (CYC) or Mycophenolate (MMF), Prefer MMF if at risk of infertility, or of Asian/African/Hispanic ancestry [can consider adding if refractory a Calcineurin inhibitor (CnI ex tacrolimus), B-lymphocyte target biologic (ex ritux, belimumab)] Class V: ACEi/ARB for proteinuria and good BP control, statin – If nephrotic range proteinuria – add Glucocorticoid + 1 of MMF, AZA, CYC, CnI, Ritux, AZA. – If progressive renal dysfunction (i) Renal US to R/O renal vein thrombus (ii) Consider repeating renal biopsy (possible concurrent class III/IV) (iii) May need additional immunosuppression

Answer 13

IgA Nephropathy** (Great oral scenario question) – Most common cause of GN worldwide (esp Asians > Caucasians, rare if African descent) – Associated with celiac disease, autoimmune disease, hepatitis, HIV, cirrhosis (and others) – Various presentations: microscopic hematuria, gross hematuria, proteinuria, RPGN or nephrotic syndrome – *can mimic nephrolithiasis presentation – Flares with ANY infection (“syn-pharyngitic”) – HSP: systemic IgA vasculitis with arthritis, purpura, GI symptoms * Diagnosis: clinical (rarely need kidney biopsy – unless to confirm clinical diagnosis), + look for 2o causes above!) * Prognosis dependent on degree of proteinuria and HTN control – <0.5g/ day: low risk of progression – Overt proteinuria and/or high Cr: Progression to ESRD = 15-25% at 10 years * Treatment: – ACEi or ARB if proteinuria >0.5g/day; titrate to proteinuria <500 mg-1g/day – Adequate BP control (SBP<120) – Fish oil not clearly established, not recommended in guidelines – KDIGO Glomerulonephritis Guideline 2021 – Consider steroids x 6 months if high risk of progressive CKD – High risk of progression= refractory proteinuria >0.75-1g despite optimal medical therapy with RAAS blockade x 90d – Counsel about risks of treatment toxicity (infections etc)

Answer 14

Nephrotic Syndrome: * Nephrotic range proteinuria (>3.5g) * Edema * hypoalbuminemia * Dyslipidemia & lipiduria

Answer 15

Diagnosis - usually* requires biopsy *unless PLA2R antibody + normal renal function– can forego biopsy, but still do screening for 2o causes General Care – Edema: Na restriction + loop diuretics (1st line, add other diuretics as needed) – Hypercholesterolemia: Statins, heart healthy diet – Proteinuria: ACEi, BP control – Thrombosis: CONSIDER “Prophylactic” full-dose anticoagulation w warfarin if – albumin <20-25 AND any of: BMI>35 | Inherited thrombophilia (ex FVL) | NYHA 3-4 | Prolonged immobilization | Proteinuria >10g/day | Recent orthopedic or abdominal surgery – If high bleeding risk, KDIGO suggests ASA 81mg daily instead – DOACs = not studied in NS, highly –protein bound in blood so not ideal Definitive management – Immunosuppression in most 1o Cases – Minimal Change, FSGS : Steroids – Membranous: Risk evaluation for progression to renal failure– low risk (wait and see) Higher risk - immunosuppressants – Treat underlying cause if 2o Cause

Answer 16

* HCV renal disease: MPGN +/- cryoglobulinemia – Classically low C4 (but not always); high RF – Clinically: nephritic/proliferative picture, palpable purpura, arthralgias, weakness, peripheral neuropathies * HBV renal disease: membranous, MPGN, polyarteritis nodosa (PAN) – 1-5% of patients with HBV develop PAN (think of this if stem points to PAN) – Clinically: pre-renal AKI, renal infarcts with PAN * HIV-associated nephropathy (HIVAN): collapsing FSGS – Clinically: Black males, advanced HIV (CD4 <200), nephrotic, high Cr – Treatment: HAART and RAS blockade

Answer 17

Pre-renal – Hypovolemia (dehydration, hemorhhage, vomiting, rhabdomyolysis, tumor lysis syndrome) – Cardiorenal/heart failure – Sepsis, anaphylaxis – NSAIDS, contrast, ACEi * Intra renal – AIN – Nephrotoxic drugs – GN, autoimmune disease, vasculitis – Thrombosis – Sickle cell – Abdominal compartment syndrome – Rhabdomyolysis (pigment nephropathy) * Post renal – Obstructive uropathy

Answer 18

Causes – Drugs (#1 cause) – Infections – Systemic illnesses: “The S’s”: SLE, sarcoid, Sjogren’s, IgG4 disease * Presentation – Timing: 1 week to weeks/ months following. **If previous exposure to drug, can occur sooner** – Acute renal failure, sometimes with fever and/or rash – Hematuria, non-nephrotic range proteinuria – Pyuria (WBC in urine) and WBC casts (not always) – Eosinophils may be increased in blood and/or present in urine (not always) * Common drugs (not a dose-dependent effect): – Anti-inflammatory: NSAIDs, COX-2 inhibitors – Anti-biotics: penicillins, cephalosporins, sulphonamides, rifampin, cipro, septra – Anti-gout: allopurinol – Anti-acid: PPI’s – Anti-edema: loop diuretics, thiazides – Immunotherapy * Treatment – Remove offending agent. – If severe renal failure, often biopsy – especially if requiring dialysis! – In select cases, consider empiric glucocorticoids if severe renal failure, but also arrange for bx.

Answer 19

Contrast-induced nephropathy (CiN) – PREVENTION: None * Hold metformin, RAS , diuretics, SGLT 2, avoid NSAIDS prior to the study * Ensure euvolemia (3 ml/hg/hr 1 hour before procedure, 1ml/kg/hr 6 hours after procedure for CKD) – TIMING: 1 – 3 days post contrast load – COURSE: nonoliguric, most self resolve in 1 – 2 weeks – Treatment: supportive

Answer 20

* Symptoms: Muscle pain, weakness, cola coloured urine – Malaise, fever, tachycardia, nausea, vomiting in some * Physical exam: muscle tenderness and swelling * Lab findings: high CK, + RBC on dipstick, - blood on microscopy – AKI from hypovolemia and third spacing – Hyperkalemia and hyperphosphatemia from damaged muscle cell rupture – Hypocalcemia from deposition of calcium salts in damaged muscle – Uricemia from rupture of damaged muscle cells – Metabolic acidosis * Treatment: – IV fluids – Management of electrolytes – Do not treat hypocalcemia

Answer 21

***ACUTE REJECTION! (always suspect this)*** – Often varying degree of proteinuria, hematuria – Requires biopsy to diagnose – Immunosuppressive med levels can be low * Medication induced (Cyclosporine, Tacrolimus) * Reversible, bland sediment, no blood or protein, immunosuppressive med levels will be high * Infection (bacterial - anytime, BK virus – later complication) – WBC in urine, mild proteinuria/hematuria, tenderness over graft if pyelo * Renal artery/vein thrombosis, * Usually early post-operatively. Requires urgent ultrasound with dopplers * Hydronephrosis * Recurrence of primary disease * PTLD (later complication) * (Causes of AKI in native kidneys)

Answer 22

* Secondary to chemotherapy – Volume depletion from nausea, vomiting, diarrhea – Sepsis from immunosuppression – Chemotherapy related nephrotoxicity (cisplatin, carboplatin, mtx, gemcitabine, paclitaxel, doxorubicin, vincristine) -> can be directly nephrotoxic or cause TMA, AIN, hypertension * Secondary to malignancy spread – Tumor infiltration of the kidney (seen on renal imaging) – Obstructive nephropathy from retroperitoneal lymphadenopathy (seen on renal imaging) * Hematologic emergencies – DIC (hemolysis) – TLS (high K, high uric acid, high phos!) * Hypercalcemia * GN (membranous nephropathy à will see nephrotic range proteinuria) * Malignancy specific – Multiple myeloma à Cast chain nephropathy (will cause non albumin proteinuria) – Waldenstrom à hyperviscosity – Amyloid à fibril deposition (congo red positive + nephrotic range proteinuria)

Answer 23

* Contrast (see AKI with Angiography slide) * ACEi / ARB: pre-renal azotemia/ischemic ATN – Failure of efferent arteriole to constrict if volume contracted – Usually concomitant history of poor PO intake and/or GI losses * NSAIDs: pre-renal azotemia/ischemic ATN, AIN, membranous nephropathy, minimal change disease – Prostaglandin inhibition- constriction of afferent arteriole (mechanism of pre renal) * Lithium: tubular disease – Nephrogenic DI – Chronic tubular-interstitial disease (use amiloride) * Aminoglycosides/cisplatinum chemo: toxic ATN/ tubular injury – Non-oliguric; * Vancomycin: rare; mechanism unclear, associated with supratherapeutic levels – Recent systematic review/ meta analysis in Critical Care Med: continuous infusion of vanco associated with 53% reduction in odds of AKI (Flannery et al. June 2020) * PPI’s: Acute interstitial nephritis

Answer 24

abnormalities in either kidney structure or function for >3 months -Albuminuria ACR >3 mg/mmol -Urine sediment abnormalities -Electrolyte abnormalities due to tubular disorders -Structural abnormalities detected by imaging -Kidney Transplant hx. -eGFR< 60mL/min/1.73m2

Answer 25

1. SGLT2i for all CKD (+/- diabetes, eGFR ≧ 20*, ACR > 20 mg/mmol) * Prevent composite of decline in eGFR, progression to ESRD, kidney death, all cause mortality, nonfatal MI, hosp for HF (CCS 2022) * Continue until dialysis or transplant (KDIGO 2022) 2. Blood Pressure: (Hypertension 2020 guidelines) * ACEi or ARB first line * Diuretics if evidence of increased salt/water retention 3. Dyslipidemia: * CCS - Age ≥ 50 years and non dialysis eGFR <60 or ACR >3 mg/mmol à STATIN, add ezetimibe 2nd line, bile acid sequestrant as 3rd /alternate * KDIGO- In adults aged ≥ 50 years with GFR categories G3a-G5 but not treated with chronic dialysis: statin or statin/ezetimibe àIn adults aged ≥50 years with CKD and GFR categories G1-G2: statin or statin/ezetimibe 4. Glycemic control optimization if diabetic (SGLT2i, GLP1RA) 5. Smoking Cessation 6. Proteinuria: <500 mg – 1 g/d (ACEi/ARB). DM2: proteinuria as low as possible

Answer 26

– Hb 100-110, Tsat >30% – K <5 – HCO3 > 22 – PO4 and Ca toward normal range – PTH target unknown for pre-dialysis CKD – PTH target for dialysis patients is 2-9x ULN

Answer 27

Anemia: Rule out other causes of anemia, e.g. blood loss If Hgb < 100: – 1st step: Iron studies * Ferritin ≤ 500, Tsat ≤30%: Oral or IV iron (prefer IV if feasible & no Contraindications) * Monoferric (ferric derisomaltose) or Venofer (iron sucrose) – 2nd step: Hb <100 and iron replete or after trial – Erythropoietin-stimulating agent (ESA)*: Eprex or Aranesp – Target Hb while on ESA: no higher than 115 * Hb >115 with ESA associated with stroke, CAD, HTN

Answer 28

Hyperkalemia: target K <5 – Potassium-restricted diet – Diuretics may help – K binders (sodium zirconium) – Avoid NSAIDs, look at other medications * Metabolic acidosis: target normal HCO3 – Sodium bicarb tabs to keep HCO3 >22 – RCT evidence to slow decline in GFR!

Answer 29

Hyperphosphatemia: target normal PO4 – Decreased renal PO4 excretion due to low GFR – Low PO4 diet – Oral phosphate binders with meals * calcium-containing: e.g. calcium carb (TUMS) – TYPICALLY FIRST LINE sec to cost – But avoid if hypercalcemia, adynamic bone disease, vascular calcification * Non-calcium containing: e.g. sevelamer or lanthanum Hypocalcemia: target normal Ca –Decreased 1-α-hydroxylase activity –Rx: calcium carbonate and calcitriol (1,25 Vit. D) **Can’t use vitamin D if hyperphosphatemic

Answer 30

Target PTH 2-9x ULN in dialysis patients * What if PTH is >9x ULN? – Calcitriol (1,25 Vit. D) but only if PO4 and Ca are not high – Cinecalcet (calcimimetic): activates Ca-sensing receptor to shut off PTH secretion – Surgical parathyroidectomy in selected patients

Answer 31

Management of Complications - Osteoporosis * CKD 1-2: with osteoporosis and/or high risk of fracture, manage as per general population * CKD 3 +: PTH in the normal range and OP / high risk of fracture, manage as per general population (2B) * CKD 3+: with biochemical abnormalities of CKD-MBD and OP or fragility fractures: “tx takes into account the magnitude and reversibility of the biochemical abnormalities and the progression of CKD, with consideration of a bone biopsy (2D)”... * In real life: * Can consider anti-OP medications if eGFR permits and optimized MBD parameters * Most Bisphosphonates acceptable down to eGFR 30-35 * Beware of the risk of severe hypocalcemia with bisphosphonates or denosumab use in CKD * Anti-OP meds are not the answer for dialysis patients

Answer 32

* Urgent/In hospital indications: AEIOU: – Acidosis (severe) – Electrolyte problems, i.e. hyperkalemia – Intoxication: methanol, ethylene glycol, Li, ASA – Overload, volume – Uremia: pericarditis, encephalopathy/seizures **Dialyze if REFRACTORY to medical management** **Note: Anuria/oliguria is technically NOT in itself an indication to start** **AKIKI and STARRT AKI (see bonus slides for trial summaries) * Non-urgent/Outpatient * Uremic symptoms/ Quality of life

Answer 33

* Anorexia, N/V, weight loss, appetite loss * Metallic taste in mouth * Pericarditis: doesn’t usually show classic diffuse ST elevation * Peripheral neuropathy * Bleeding, i.e. platelet dysfunction * CNS: mental status changes, seizures, mood disorder * Amenorrhea, decreased libido, erectile dysfunction * Nocturia, restless legs (related to iron deficiency) * Pruritus

Answer 34

First line for diabetes with CKD 1. metformin (gfr >30) * eGFR 30-44 – initiate at 1⁄2 dose and titrate upwards to half of max recommended dose * Monitor b12 annually (once on met 4+ yrs) * Monitor renal function q3-6mos 2. SGLT 2i (eGFR >20-30*) ↓ MACE (empa, cana), Hospitalization for HF, Progression of nephropathy Add On: 1. GLP 1 agonist ↓ MACE (liraglutide, semaglutide) Treatment with ACE or ARB for DM2 with HTN + albuminuria – Consider for albuminuria without hypertension – Repeat Cr, BP, K in 2-4 weeks – Accept up to 30% rise of creatinine within 4 weeks * Above 30%? Think volume depletion, NSAIDs, AKI, RAS... – Advise contraception – Hyperkalemia: dietary change, consider K binder before altering RASi dose * Treatment with SGLT 2i – Gfr > 20 ml/min, and can continue if gfr falls below 20 unless starting dialysis – Does not apply to transplant patients – Hold SGLT2 in fasting, surgery, critical medical illness * Treatment with non steroidal MRA (finerenone – now in Canada) – For DM2, gfr >25 ml/min, normal K, albuminuria 30mg/g despite max RASi

Answer 35

Urinalysis dipstick – Protein: hypertension, diabetes, MM, GN, orthostatic proteinuria, nonpathological (illness, fever, exercise, pregnancy) – Glucose: DM, pregnancy, SGLT 2 inhibitor, tubular dysfunction (MM) – Ketones: starvation, DKA, alcohol, poisoning – Leukocyte esterase and nitrites * Urinalysis microscopy – Erythrocytes > 3 * Isomorphic vs dysmorphic * + blood on dipstick with negative erythrocytes = rhabdomyolysis, hemolysis, mechanical valve – Leukocytes > 5 : infection – epithelial cells * Squamous: contamination. Renal tubular epithelial: ATN, transitional : ureters * Casts: – Hyaline cast: CKD – WBC cast: AIN or infection – RBC cast: GN – Granular cast: ATN – Tamm Horsfall : normal * Crystals – Calcium phosphate, calcium oxalate, uric acid, struvite

Answer 36

Ultrasound – Echogenicity: acute or chronic parenchymal disease * Kidney stone: non contrast CT * Hematuria: CT urography or cystoscopy * Renal mass: MRI * Doppler/CTA/MRA: renal artery stenosis

Answer 37

* Indications: nephrotic/nephritic, especially when it will change management * Risks: – Most common complication: bleeding (hematuria is expected), pain at biopsy site – Need for transfusion 1%, requirement for intervention to control bleeding < 1%, death 0.06% * Medication management – Ideally would be best to stop antiplatelets 5 days before and resume 5 days post biopsy. But research shows that patients continuing asa at time of biopsy did not report increased risk of bleeding – Anticoagulation: involve a specialist! Individualize management * Warfarin: allow INR < 1.5, * bridge with heparin depends on patient * IV heparin: stop 6 hours prior and allow apTT to normalize, resume 12-24 hours later * LMWH: stop the day prior and resume 48-72 hours later * DOAC: there is no data – DDAVP is commonly given to prevent bleeding – Blood pressure should be controlled < 160 pre biopsy * Contraindications: – UTI, uncooperative patient, bleeding diathesis, uncontrolled hypertension, poor visualization, infection – Relative: solitary kidney, hydronephrosis, small kidneys

Answer 38

Renal Cysts - Bosniak classification (based on CT) (CT preferred, however it is with Contrast! If CKD or contraindication to contrast: radiologists will also classify based on US) * Bosniak 1 and 2: <5% are cancer – Simple cysts with thin walls, no (stage 1) or fine (stage 2) calcifications, and no (1) or thin (2) septae, no enhancement – No need to follow up * Bosinak 2F (F for ‘follow-up’) – approx 10% are cancer – Smooth, minimally thickened wall. May have multiple septa, but smooth without contrast enhancement – Needs active surveillance: repeat imaging at 6 mo, 12 mo, then yearly * Bosniak 3: 50% are cancer – One or more enhancing thick or irregular walls or septa * Bosniak 4: 90% are cancer – Like Bosniak 3 but also have a solid enhancing nodule Bosniak 3 and 4 should be referred for partial nephrectomy – If not fit for surgery, go for perc biopsy or active surveillance. Possible thermal ablation if candidate

Answer 39

Solid Renal Mass * Image CT or MRI * <1cm: too small to really workup – Needs active surveillance * >1cm: vast majority are actually cancer – If scan shows lesion is clearly an angiomyolipoma, then no further w/u is needed – Otherwise, first check for metastases, then: – If life expectancy >5 years, partial nephrectomy – If life expectancy <5 years, or not fit for surgery, consider perc biopsy, active surveillance or thermal ablation (Beyond the scope of this exam!)

Answer 40

* Polycystic Kidney Disease is an autosomal dominant disorder resulting in growth of renal cysts that destroy normal renal parenchyma * Affects 1/1000 live births * Diagnosis done by family history and imaging: Unified Criteria **in absence of family history, NO validated criteria to diagnose ADPKD based on US imaging** PKD1 progresses faster than PKD 2 Unified Criteria (for US diagnosis of ADPKD in patients with + family history): -If age 15-39 ≥ 3 cysts total -If age 40-59 ≥ 2 cysts per kidney Common symptoms: – HTN – pain- most common symptom; abdo pain common in cyst rupture – hematuria- often from cyst rupture, proteinuria – Stones- uric acid stones , Ca Oxalate – UTI- 4 weeks antibiotics if infected cyst! – concentrating deficit- thirst, polyuria, polydipsia, nocturia – Erythrocytosis- ↑ epo levels – Extra-renal manifestations- liver cysts, diverticuli, cerebral aneurysms, pancreatic cysts Mitral Valve Prolapse/ AI most common cardiac anomalies

Answer 41

Recommend all ADPKD patients be referred to nephrology for initial assessment, which should include imaging and consideration of genetic testing * Diagnose on imaging: – If known family history of PCKD– Ultrasound is serially preferred imaging – If no prior family history, US, MRI, or CT can be used – ALL patients should have baseline imaging to assess total kidney volume (TKV)- preferred method is MRI or CT – Follow up imaging should not exceed a frequency of once yearly * Treatment – Sodium restriction to <2g/day, high fluid intake – 18-50 years with eGFR >60 and without significant CV morbidities target BP of ⩽110/75 mm Hg – Tolvaptan therapy for specific patients– For reference only, outside the scope of this exam * TEMPO candidates: 18 to 50 years with TKV >750 mL and eGFR >60 * REPRISE candidates: 18 to 55 years with eGFR of 25 to 65 OR 56 to 65 years with eGFR of 25 to 44 with evidence of a decline in eGFR >2/year

Answer 42

* Pathogenesis: – Increased excretion of solutes: calcium, oxalate, uric acid – Decreased urine volume – Abnormal urine pH * Alkaline: calcium phosphate, struvite * Acidic: calcium oxalate – most common, uric acid, cysteine (AR, genetic) – Absence of inhibitors: citrate, magnesium – Structural kidney disease * General work-up (outside of acute setting): – Urinalysis, urine culture – Electrolytes, Cr, Ca, PO4, PTH, uric acid – 24 hour collection for volume, Na, Ca, PO4, uric acid, oxalate, citrate, Mg, – Urine Creat (to assess for adequate sample)

Answer 43

Myeloma Kidney (Seen with myeloma and other monoclonal gammopathies) – Cast nephropathy – Light chains both toxic to and clog tubules à AKI – Other mechanisms of AKI: hypercalcemia, hyperviscocity syndrome (Waldenstroms) – Tubular proteinuria, but dipstick negative (dipstick for albumin only!) – Fanconi’s like syndrome – Risk factors: NSAIDs, Lasix, IV contrast – Treat the myeloma – Extracorporeal methods to remove SFLC (plasmapheresis and high cutoff dialysis) can be used as adjunctive therapy – not great evidence and not for the scope of this exam Amyloid Kidney – Deposition of fibrils in tissues – Congo red positive, apple-green birefringence – Deposit in glomerulus- leak albumin à nephrotic syndrome AL amyloid: clonal light chains deposit in glomerulus – Treat with chemotherapy Other: MGRS (monoclonal gammopathy of renal significance – multiple etiologies) *Note* AA amyloid: chronic inflammatory disease leads to amyloid creation, deposits in kidney – Treat underlying disease: e.g. RA, TB, chronic osteomyelitis