week 10- renal 2 Flashcards
• Acute renal failure (ARF):
o Aka acute kidney injury (AKI)
o =GRF abruptly ↓ (w/i 48hrs) →sudden retention of normally cleared endogenous and exogenous metabolites (urea, K, PO4, SO4, creatinine, drugs)
o High risk: DM2, HTN, geriatrics
o General presentation (variable): Azotemia (N&/V, malaise, altered sensorium), Arrythmias from hyperkalemia, Ecchymoses dt plt dysfxn, Pericardial effusion, cardiac tamponade, Sz dt electrolyte imbalance, Fasciculations and mm cramps, Perioral paresthesias dt hypocalcemia, Peripheral edema (↑wt), Skin pallor, Hyper/hypovolemia
• Pre-renal ARF, causes, ssx:
o MC (60% community-acquired): inadequate perfusion to KD dt inadequate circulation or volume o ↓intravascular vol= Hemorrhage, dehydration, ↑diuresis, extravascular space sequestration, pancreatitis, burns, trauma, peritonitis o Change in vascular resistance= Sepsis, anaphylaxis, drugs (ACE inhibitors, NSAIDs, epi, norepi, cyclosporine), RAS o ↓CO= CHF, pulm emb, pericardial tamponade o SSX: Dehydration, thirst, dizziness, mental status change, Poor skin turgor, collapsed neck veins, dry mucous membranes, orthostatic BP
• Pre-renal ARF work-up:
o Oliguria (↓400ml/d), emergency! If ↓100 mL (anuria), SG >1.018
o Normal urine osm (>500 mOsm/kg), Urine Na ↓10 mEq/L, FENa ↓1%
o BUN/creatinine >20:1 (azotemia)
o UA: No changes in urine sediment, no protein, cells or casts
o MRI or doppler US: Locate and assess vascular abnormality
o CXR: to evaluate CHF
• Renal (intrinsic) ARF, causes:
o Dt injury in renal tubules, interstitium, vasculature or glomeruli
o mc ATN (80%), ischemic or toxic
o ATIN (10-15%)
o Acute GN (eg PIGN, RPGN)
o Acute PN
o Vascular dzs: vasculitis, polyarteritis nodosa
o Nephrotic syndrome (mult causes)
• Renal ARF ssx, work-up:
o Ssx: vary w cause: Hx URI, diarrhea, use of Abx or IV drugs; Back pain, gross hematuria, fever (PN), Maculopapular rash (interstitial nephritis), Dehydration and shock
o UA: SG ↓1.012, Urine osm ↓350 mOsm/kg, Urine Na >40 mEq/L, FENa >1%
o Variables: Granular casts=ATN, GN, ATIN; WBC casts=PN; RBC casts=PIGN; Eosinophiluria=ATIN
o CBC: ssx anemia, infx
o CMP: ↑ BUN, Creatinine, ratio ↓10:1
o Cystatin C: ↑ when creatinine is still N (early in course)
o ↓serum complement, circulating immune complexes
o Renal bx shows characteristic changes
• Post-renal ARF, causes, ssx:
o urinary flow from both KDs obstructed → ↑nephron intraluminal back pressure, ↓GFR o Causes: BPH, tumors of bladder, prostate, cervix or pelvic area, urolithiasis, renal V stenosis, neurogenic bladder; post-surgical or trauma; anticholinergic drugs o SSX(depend on cause): Renal pain and tenderness, lo abd pain, post-surgery urine leak, edema, ileus w abd distention, enlarged prostate on DRE, distended bladder
• Post-renal ARF work-up, management:
o Lab: normal urine osm, ↑BUN and creatinine, crystals or hematuria
o US: mb hydronephrosis
o Cystoscopy: mb utereral obstruction
o CT or MRI: mb mass causing obstruction
o Manage: mb Refer for dialysis; Find and treat cause, assess pt vitality; Monitor Vitals, input/outputs, electrolytes, BUN/creatinine
• Chronic renal failure, ssx:
o Aka ESRD or “chronic kidney dz” CKD
o = ↓ KD clearance of certain solutes → retain fluids/toxins, progress over mos-yrs. Difficult to identify onset and predict course
o ARF may →irreversible CRF
o General SSX: HTN, edema, osteodystrophy, anemia of chronic dz, uremia
• Causes of CRF:
o Glomerulopathies: Primary: FSGS, IgA nephropathy, membranous nephropathy; Secondary: diabetic nephropathy, amyloidosis, heroin abuse, PIGN, SLE
o Tubulointerstitial nephritis: Drug hypersensitivity, heavy metals, analgesic nephropathy, chronic PN
o Heredity: PKD, Alport syndrome
o Obstructive nephropathy: Prostate dz, nephrolithiasis, retroperitoneal tumor, congenital
o Vascular: Hypertensive nephropathy, RAS
• Ssx of uremia (CRF):
o General: Fatigue, weakness; Sallow-appearing
o Skin: Pruritis, easy bruising; Pallor, ecchymosis, edema
o ENT: Metallic taste, epistaxis; Urinous breath
o Eye: Pale conjunctiva
o Pulm: SOB; Crackles, pleural effusion
o CV: DOE, retrosternal pn on inspiration; HTN, cardiomegaly, friction rub
o GI: Anorexia, N/V, hiccup
o GU: Nocturia, impotence; Isosthenuria
o Neuromuscular: Restless legs, numbness, cramps in legs
o Neuro/MSE: Irritability, poor concentration, depression; Stupor, asterixis, myoclonus, peripheral neuropathy
• Labs for CRF:
o Microalbuminuria (N = ↓20 mg/L, abN >50), WBCs, waxy casts,
o Proteinuria: magnitude predicts rate of progression of ESRD
o Blood: total protein, electrolytes, BUN /creatinine, reticulocytes; Spot check Alb/creatinine (want ↓30)
o Hypercholesterolemia (>400 mg/dl); Anemia, met acidosis, ↓Ca, ↑K, ↑P
o ANA (SLE), Cystatin C (cysteine proteinase inhib) (filtered, not secreted)
o Estimate GFR with serum creatinine
• Imaging for CFR:
o US: BL small kidney, cortical thickness
o Xray: slow bone growth, osteomalacia, renal osteodystrophy
o Avoid contrast dyes
• Staging of CRF:
o 0: Risk factors for CRF (HTN, DM), GFR ≥90 w/o albuminuria; Every 6 mos: check BP, microalbumin, creatinine, HbAIC
o 1: KD damage w N GFR (≥ 90 w albuminuria); tx cormorbid dz
o 2: Ki damage w mild ↓GFR (60-89); Estimate progression
o 3: Mod ↓GFR (30-59); Tx complications
o 4: severe ↓ GFR (15-29); prep for replacement
o 4: KD failure, GFR ↓15, replacement, dialysis
• Renovascular dos:
o Benign hypertensive arteriolar nephrosclerosis
o Renal artery stenosis/occlusion
o Renal vein thrombosis
• Benign hypertensive arteriolar nephrosclerosis
o Chronic HTN damages microvasculature, glomeruli, tubules, interstitial tissues → nephrosclerosis. Over years may → ESRD (common!)
o Risk factors: aging, poorly controlled HTN, DM, African-Americans
• Renal artery stenosis/occlusion
o stenosis of one or both renal a (atherosclerosis): → refractory HTN, abd bruit o occlusion (thromboembolism): → flank pain, abd pain, fever, N/V, hematuria. Mb ARF; Seen on CT angiography
• Renal vein thrombosis:
o → occlusion of one or both renal veins. Causes include hypercoagulability, nephrotic syndrome, amyloidosis, estrogen therapy, pregnancy, SLE
o SSX: RF, st N/V, flank pain, gross hematuria, ↓urine output; Seen on MR venography and Doppler US
• Renal masses:
o Polycystic kidney disease (PKD or ADPKD)
o Renal cell carcinoma (Adenocarcinoma) (RCC)
o Wilms’ Tumor (nephroblastoma)
• Polycystic kidney disease (PKD or ADPKD), ssx:
o AD, BL KD cysts that ↑ in size, disrupt normal KD fxn. may become infected and bleed
o typically manifests >40; mb hepatic, splenic, pancreatic, CNS arachnoid cysts
o ssx: asx early; as cysts ↑: Pain over both kidneys, “drag” from heaviness; Pain w infx, obstruction, hemorrhage (ruptured cyst); infx: fever, chills, tender kidney(s)
o Gross hematuria; HTN (look for retinopathy); nocturia
o Renal insufficiency: HA, N/V, ↓wt
o Palpable, nodular kidneys
• Work-up for PKD:
o Lab: mild proteinuria, hematuria varies, pyuria; ↑EPO → ↑Hb and HCT; Anemia from blood loss; Progressive uremia from renal insufficiency (↑BUN and creatinine)
o KUB: ↑renal shadows up to 5x
o CT: 95% accurate for dx, can detect cysts from 0.5cm
o US: can detect cysts from 1-1.5cm (Most cost effective, usu start here)
o MRI can differentiate RCC from cysts
• PKD px:
o > 50% become uremic w/in 10 yrs sx onset
o Course is variable, many reach ESRF > 20 yr
o Dialysis or transplant then required
• Renal cell carcinoma (Adenocarcinoma) (RCC), incidence, risks factors:
o Arise from glandular tissue: 85% of all primary malignant renal tumors, increasing incidence. ~1:10,000 cases/yr o M (3:1) in 50’s-70’s. ↑ black and Hispanic M o Risks: Cigarettes, chronic analgesic use, ADPKD, obesity, toxin exposure (Cd, Pb, asbestos, PAHs), coffee, animal fat diet, dialysis, hysterectomy, contrast IVU
• RCC ssx:
o “great masquerader” (mb few sxs)
o Classic triad: gross hematuria, flank pain, palp abd mass
o Fever, ↓wt, HTN
o M: possible L varicocele dt blockage L testicular v
o mets: dyspnea, cough (lung), seizure (brain), bone pain
• RCC work-up:
o Gross or microscopic hematuria in 60%
o ↑ESR; normochromic/normocytic anemia; ↓serum iron, ↓TIBC
o Abn LFT from toxin build-up (↑ALP,↓albumin)
o Possible: ↑alpha-fetoprotein (>500 ng/ml), B-hCG
o renal bx and fine needle aspiration
o US: defines simple cysts, tumor thrombus (do first)
o CT: method of choice to stage, extent of brain mets
o CXR useful for mets; radionucleotide for bone mets; MRI for vascular extension
o PET: monitor response to systemic tx
• Wilms’ Tumor:
o aka nephroblastoma
o =Mixed malignant tumor of KD, kids > adults, 3.5 yrs.
o Abn proliferation of metanephric blastema cells, genetic predisposition
o SSX: abd mass, abd pain, HTN
o Lab: hematuria, anemia
o US or CT
• Interstitial Cystitis/ Painful Bladder Syndrome (IC/PBS), hx:
o Fibrosis of bladder wall → ↓bladder capacity. Chronic inflam w mucosal disruptions, cellular infiltrates, sub-urothelial hemorrhages
o Micro: Hunner’s ulcers or glomerulations (petechial hemorrhages)
o ~500,000 people in US, 90% in whites and F
o Dx of exclusion
o Hx: Use “Pelvic Pain/Urgency/Frequency Patient Survey”
o “Flare up” of sxs linked to common foods (do diet diary!)
o Triggers mb: Coffee, carbonated drinks, cranberry, tomatoes, alcohol, vinegar, chocolate, strawberries, tea
• IC/PBS ssx, PE:
o SSX: freq/urgency (mb ever 10 mins!); bladder pain, worse full bladder, better voiding
o Very poor QoL
o Mb non-specific pelvic pain, dyspareunia
o Often exacerbations and remission of symptoms
o PE: mb normal, suprapubic tenderness; Variable tenderness of abd wall, buttocks, pelvic floor, urethra. F: mb no gyn exam dt tenderness. M: mb scrotal and penile tenderness
• IC/PBS work-up:
o Lab: UA: no signs infx, mb hematuria; Normal renal fxn tests unless obstruction or reflux
o Cytology: if at high risk for bladder CA
o Potassium sensitivity test (PST): infiltration causes pain
o Cystoscopy: bladder wall inflam, edema, small mucosal disruptions, cellular infiltrates, glomerulations, punctate hemorrhages
• IC/PBS dx criteria, ddx:
o Patient must have: Either Glomerulations OR Hunner’s ulcers on cystoscopic exam
o AND Either pain assoc w bladder OR urinary urgency
o No other diagnosable condition
o Ddx: TB of bladder, Schistosomiasis, cystitis, vag wall prolapse, urethritis, spastic neurogenic bladder, anxiety do, prostatitis, endometriosis, uterine fibroids, CA (bladder, cx, prostate, colon)
• Neurogenic Bladder:
o Overactive (spastic) bladder: Lesions above S2-4 → loss of inhibition of parasymp effects (MS, stroke), Detrusor hyperreflexia, loss of bladder capacity; frequent urination, triggered by detrusor spasm o Underactive (flaccid) bladder: Lesions at or below S2-4 → loss of sense of fullness, ↑capacity (nerve injury), Detrusor areflexia; urine retention w overflow incontinence
• Bladder CA, incidence, risk factors:
o 2nd mc site GU tumors (prostate CA #1)
o ↑ incidence industrialized nations. ~54,000 cases/yr, 12,000 deaths
o M>F (3:1); whites >African Americans; >60yo
o Usu superficial TCC, treatable if found early
o Risks: Cigarettes (up to 65% of cases); occ exposures (solvents, aromatic amines, combustion products, etc); infrequent urination; SAD diet; HPV infx; FHx; chemotherapy
• Bladder CA ssx, PE:
o SSX: 85-90% present w gross or microscopic hematuria, usu painless
o Suspect in any pt present w unexplained hematuria
o St: nocturia, dysuria, urge incontinence
o Late: freq, urgency, dysuria, flank pain, abd pn, bone pain with mets, anorexia
o PE: early normal; Later, thickened bladder wall, HM, supraclavicular LA, pelvic LA
• Bladder CA work-up, ddx:
o Lab: Hematuria, mb pyuria, azotemia when obstruction, anemia of chronic dz
o Micro: exfoliated cells from neoplastic epithelium
o cystoscopy and bx
o Pelvic CT: extent of bladder wall invasion and enlarged nodes
o CXR, bone scans, PET scans for metastasis
o DDX: IC, UTI, urolithiasis, neurogenic bladder, endometriosis
• Urolithiasis. Incidence, etio:
o 250-750,000 cases/yr in US. M>F 4:1, 30s-50s o FHx and significant risk for recurrence of stones o Crystals (common) precipitate into stones o Changes in: intake of stone constituents, excretion of stone constituents, urine output, urine pH. o Insufficient fluid intake (↓2L/d). Dehydration (↑incidence in summer) o Many metabolic defects from GI sources
• Risk factors for urolithiasis:
o M 30-5, PM F, obese, Positive FHx
o Diet: ↑fat, animal protein (purines), sugar, Na, coffee, alcohol, ↓ fiber, fluid intake
o High oxalates: rhubarb, spinach, black pepper, black tea, cocoa, Swiss chard, parsley, beets & greens, peanuts, cola drinks, wheat bran
o Crystalluria (saturation of salts), Chronic diarrhea
o Meds: diuretics, antacids, antiHTN; Chemo
o Vitamins: ↓Mg, B6, Vit C bw meals
o Hot Climate, Socioeconomic, Occupation: white collar, sedentary
• Urinary stone types:
o Ca oxalate: mc, 75%, Radiopaque, ↓1cm, White on KUB; Low water intake, Hyperoxaluria, hypercalciuria, Hyperuricosuria, hypocitriuria, Hyperparathyroid o Struvite (Mg NH4 PO4): GU tract colonization by urea-splitting organisms Proteus, klebsiella, pseudomonas; Radiopaque, often staghorn o CaPO4 (5%): HyperPTH, RTA; Radiopaque o Uric acid: hyperuricosuria; radiolucent (black) o Cysteine (rare): cystinuria; radiopaque
• Urolithiasis ssx:
o Colic (fluctuating pain): stretching of ureter by obstruction of flow
o Non-colicky pain: dt distention of renal capsule
o Common presentation: “attack” abrupt onset flank pn, radiates to groin, severity depends on size, location of stone, degree of obstruction
o Stone Location/pain:
o Renal calyx: deep dull flank pn
o Renal pelvis: >1cm can obs ureteropelvic junction, Severe dull to sharp CVA pn, Staghorn mb silent except for recurrent UTI
o Upper/mid ureter: severe sharp CVA/flank, radiates to dermatome. May mimic appendicitis on R
o Distal ureter: radiates to groin or testicle in males, labia majora in F. Dysuria, freq, urgency, gross hematuria
o Urinary urgency, frequency in sm amts, incomplete voiding
o Restlessness (pt w peritonitis will want to stay still)
o N/V, ↑ thirst
• Stones PE, lab:
o PE: Fever if infx (not common), mb CVA tenderness, mb abd mass if obstruction and hydronephrosis
o Lab: UA: Hematuria, mb pyuria dt inflam, crystalluria
o If Infx: LE, nitrites, WBCs. Run urine C&S
o Urine protein: ↑ w infx, obs, RF
o CBC: anemia, ↑WBC w left shift
o To assess renal fxn: BUN & serum creatinine, serum electrolytes
o For stone typing: Urine pH, Strain urine for sediment
• Procedures, referral for stones:
o Procedure: for location, size, general shape (suggesting composition):
o KUB and US: can identify large and radiolucent stones (start here)
o IVU: helps distinguish ureteral stones, phleboliths, assess for obs
o Non-contrast spiral CT: best (spec ~100%) but expensive
o Refer if: >5 mm, ssx obs or KD damage (↑serum creatinine), Anuria, Staghorn calculus, Cystine stone, Persistent V, Pain unresponsive to oral analgesics
• Ddx of stones:
o a) “acute abdomen” OR b) stone-like mass on KUB
o a) Appendicitis, diverticular dz, PUD, ovarian torsion/rupture, ectopic pg, PID, bowel obs, biliary stones, renal a embolism, abd aortic aneurysm, PN, UTI
o b) phleboliths, cholelithiasis, calcified nodes, foreign body
o c) Also consider narcotic-seeking individuals
