Bean Basics
CKD can be defined as eGFR <__ for 3+ months.
60
Name 3 important lab tests to follow in CKD (especially CKD3a or higher)
BMP or renal function panel (sCr, BUN, Na, K, CO2, Ca), Hgb/Hct, Vit D, intact PTH, urine protein:Cr
CKD causes ____calcemia, ____phosphatemia, ____vitaminosis D and ____ hyperparathyroidism
HYPOcalcemia, HYPERphosphatemia, HYPOvitaminosis D, SECONDARY hyperPTH
What is the 1st leading cause of CKD in America & what is the pathology?
Diabetes Mellitus --> diabetic nephropathy
Metformin should be discontinued when eGFR <__.
30
What is a normal urine protein:Cr and albumin:Cr
<0.15 (150) and <30, respectively
Name 2 common ways in which serum creatinine can be falsely high.
High muscle mass, taking creatinine based supplements
A 58 y.o. male presents to clinic with underlying CKD4. LDL levels are 82. Do you initiate statin therapy?
Yes - Given high ASCVD risk, guidelines recommend treatment with statin regardless of cholesterol level and do not recommend targeting specific cholesterol or LDL
What are 3 signs OR symptoms in an advanced CKD patient that might signal need for hemodialysis (a.k.a call your neighborhood friendly nephrologist)?
Refractory acidosis, hyperkalemia, refractory volume overload, uremic symptoms such as progressive cachexia, abnormal taste of food (particularly meats), nausea, difficulties sleeping (that is new in onset).
What is the 2nd leading cause of CKD in America & what is the pathology?
HTN --> hypertensive nephrosclerosis
How do we define oliguria in renal failure?
<400-500 mL/day (normal = 1-2 L)
What urine protein:Cr is considered "nephrotic range" and where does that typically localize the pathology to within the nephron?
>3.5, usually glomerular (as opposed to tubulointerstitial or overflow as alternate etiologies)
What is the leading cause of death among patients with CKD?
Cardiovascular disease
What test commonly examines the "echogenicity" of the kidney and can help rule-out structural causes of AKI/CKD?
Renal Ultrasound (recommended in all new CKD workup)
A 28 y.o. female presents with "foamy" urine. UA reveals >500 protein, urine TP:Cr is 8.2. Serum creatinine is 0.81. What would you expect to find on her lipid panel?
Secondary dyslipidemia including high LDL 2/2 nephrotic range proteinuria.
What part of the nephron does hypertension affect (Hint: same as NSAIDs)?
Tubulointerstitium (NOT glomerular)
At what bicarbonate level is bicarbonate therapy indicated in the management of chronic metabolic acidosis associated with CKD?
Bicarbonate <22
A new patient presents to the office for a physical. Labs return with a spot urine albumin to creatinine ratio (ACR) of 0.46. Blood pressure is 143/90 in the office confirmed on home reads. What first-line class of medications would be used to treat this patient?
ACEi or ARB. An argument could also be made to use SGLT-2 inhibitors (if GFR allows) to slow progression of renal impairment.
Why should providers ask about high risk sexual activity or IVDU in new CKD patients?
HIV and Hep B/C are potential causes
Name 3 indications for nephrology referral in a CKD patient.
eGFR <30 (CKD3b+), unclear CKD etiology, rapid GFR decline, progressive electrolyte derangement, uremia, structural disease (e.g. PKD). Any patient with persistent hematuria + CKD should have at least one time
A 53 year old female with CKD3b 2/2 diabetic nephropathy on Irbesartan presents for follow up. Labs reveal potassium of 5.8. Name 3 things you can do as an outpatient to lower her potassium.
Low K diet, add loop diuretic, potassium binder (Veltassa, Lokelma; usually need Nephrologist and/or PA), check other medications
A 38 y.o. female with strong FHx of kidney disease and "brain bleeds" has an abnormal eGFR and abdominal fullness on exam. What is the concerning diagnosis?
Autosomal dominant PKD
A 55 y.o. female with CKD4 comes in with BP 156/90. She is on Amlodipine 10 mg, HCTZ 25 mg, Coreg 25 mg BID and has been unable to tolerate ACEi/ARB due to hyperK. She requests qd medications. What is the best option to consider?
Discontinue HCTZ, start daily Torsemide. Could consider alpha blocker, though less common.
A patient has a known history of diabetic nephropathy with CKD3b. The patient developed widespread erythematous rash with ACEi as well as ARB. What is another medication class that can be used to reduce proteinuria?
Aldosterone antagonists spironolactone, epleronone) or non-DHP calcium channel blockers (verapamil, diltizem)
CHALLENGE: Name a condition with CKD but relatively preserved eGFR (Hint: common podocytopathy)
Minimal change disease (early nephrotic range proteinuria)
What are the indications for iron supplementation and EPO in CKD patients (Tsat, ferritin, EPO)?
Fe: Tsat <20%, Ferritin <100; Hgb 9-10
What is the most likely mechanism of hypertension in CKD?
Ineffective sodium excretion leading to subtle volume expansion
CHALLENGE: While awaiting GN workup incuding ANA, ANCA, anti-PR3, anti-dsDNA and anti-MPO you find low serum complement levels. Which is a potential diagnosis? A) IgA Nephropathy, B) MPGN, C) Wegener's, C) RPGN
B) MPGN. All others have normal or normal/high complement levels. Low C3/C4 = lupus nephritis, cryoglobulinemia, Hep B/C, and post-infectious.
What is the only true way to accurately diagnose the etiology of most CKD?
A kidney biopsy, though benefit must outweigh risk.
You are CC'ed on urine studies from a recent hospitalization. You review the labs and find a spot urine TP:Cr of 2.8 with a spot urine Albumin:Cr of 0.38. What is the significance of this finding?
There is the presence of a protein gap concerning for overlow proteinuria from increased protein production. This is concerning for monoclonal gammopathy process.