MNT 3

Main functions of the kidneys

Fluid/electrolyte balance, acid-base regulation, waste excretion, BP control, EPO & Vitamin D production.

GFR

Glomerular Filtration Rate; estimates kidney function by measuring plasma clearance.

Normal GFR

~120 mL/min or 135-200 L/day.

CKD definition

GFR

Common CKD causes

Diabetes (most common), HTN, glomerulonephritis, congenital disease.

CKD stages

Based on GFR ranges (Stage 1 ≥90 to Stage 5 <15).

MNT for CKD stage 1-2

Manage comorbidities (DM, HTN), maintain adequate nutrients.

MNT for CKD stage 3-4

Protein: 0.6-0.8 g/kg; energy: 25-35 kcal/kg; restrict Na⁺, K⁺, Phos.

MNT for CKD stage 5

Protein: 1.2-1.3 g/kg; tight fluid/electrolyte/phos control.

Protein needs in hemodialysis

1.2 g/kg/day.

Protein needs in peritoneal dialysis

1.2-1.3 g/kg/day.

Vitamin supplements to avoid in CKD

High doses of Vitamin A and C.

Causes of anemia in CKD

↓ EPO, poor iron intake, blood loss, inflammation.

Treatment for anemia in CKD

EPO injections + iron supplementation.

Causes of renal osteodystrophy

↓ Vitamin D → ↑ PTH → bone resorption.

Treatment for renal osteodystrophy

Phosphate binders, vitamin D, restrict dietary phosphorus.

Signs of hyperkalemia

Muscle cramps, irregular heartbeat, cardiac arrest risk.

Foods high in potassium

Bananas, potatoes, avocados, watermelon, beans.

Symptoms of CKD

Edema, Na retention, HTN, metabolic acidosis, anemia, bone disease.

Main goal of MNT in CKD

Slow progression, manage electrolytes, maintain nutrition status.

Key CKD labs to monitor

Serum creatinine, BUN, potassium, phosphorus, albumin.

Lactulose use

Treating hepatic encephalopathy by reducing ammonia levels.

Causes of ascites

Portal HTN and hypoalbuminemia in cirrhosis.

Nutritional management of ascites

Restrict Na and fluid, use diuretics, monitor protein status.

Causes of esophageal varices

Portal hypertension in liver disease.

MNT for esophageal varices

SFM, soft/low-fiber foods to prevent rupture.

Causes of hepatic encephalopathy

Ammonia buildup due to liver's inability to detoxify.

Protein recommendation in hepatic encephalopathy

1.2-1.5 g/kg/day (not restricted anymore).

Energy and protein MNT for ALD

30-35 kcal/kg; 1.5-2.0 g/kg PRO.

Energy and protein MNT for cirrhosis

35-40 kcal/kg; 1.2-1.5 g/kg PRO.

MNT for hepatitis

High protein and calories to support liver regeneration.

Signs of jaundice

Yellow skin/eyes, dark urine, pale stools, ↑ bilirubin.

Causes of portal hypertension

Obstruction in liver blood flow, common in cirrhosis.

Treatment for portal HTN

Beta blockers, endoscopic interventions, shunts.

MNT for pancreatitis (acute)

EN preferred, adequate kcal/PRO, rest pancreas.

MNT for pancreatitis (chronic)

SFM, low-fat, enzymes, MCTs, fat-soluble vitamins.

Steatorrhea

Fatty, foul-smelling stool from fat malabsorption.

MNT for steatorrhea

Low fat, pancreatic enzymes, MCTs.

MNT for diarrhea

Fluid/electrolyte replacement, low-residue diet, ORS.

MNT for constipation

Gradual fiber increase, fluids ≥2L/day, pre/probiotics.

Causes of osmotic diarrhea

Poorly absorbed solutes (e.g., sorbitol, lactose).

Secretory diarrhea

Infections, inflammation, bile acids; does NOT resolve when NPO.

MNT for Celiac Disease

Lifelong gluten-free diet, initially lactose-free and low-residue.

Gold standard to diagnose celiac disease

Small intestine biopsy + positive IgA antibodies.

Symptoms of Celiac

Diarrhea, bloating, nutrient deficiencies, rash, neuropathy.

MNT for IBS

FODMAP diet, normalize meals, pre/probiotics.

Difference between Crohn's and UC

Crohn's affects any GI region (all layers); UC affects colon (top layers).

MNT for IBD during flare

SFM, 1.2-2.0 g/kg PRO, low-residue/lactose-free, EN preferred.

MNT for IBD remission

Normal diet, pre/probiotics, ↑ energy/protein, antioxidants.

MNT for diverticulosis

High fiber and fluids, pre/probiotics.

MNT for diverticulitis

Low fiber, antibiotics, EN/TPN, possible surgery.

Short bowel syndrome

<200 cm of small intestine remaining → severe malabsorption.

MNT for short bowel syndrome

TPN → EN → oral; low-fat, low-oxalate, lactose-free.

Biggest risk in SBS

Massive fluid and electrolyte losses, malnutrition.

Nutrients commonly malabsorbed in SBS

Fat-soluble vitamins, B12, Mg, Ca, Zn, iron.

Dwell time in dialysis

Duration that dialysate stays in peritoneal cavity.

Dialysate

Solution used in dialysis to remove waste and balance electrolytes.

Nephrolithiasis

Kidney stones - often Ca oxalate.

Nutritional management of nephrolithiasis

Increase fluids to 3L/day, DASH diet, moderate Ca intake.

Foods high in phosphorus

Meat, dairy, dark soda, beans, whole grains.

Importance of serum albumin in liver/renal disease

Low levels indicate malnutrition or inflammation; affects fluid shifts.

Effect of inflammation on CRP

CRP ↑ in inflammation, including liver and CVD complications.

Consequences of malnutrition in CKD

PEM, poor wound healing, ↑ infection risk, muscle wasting.

Vitamins lost in dialysis

Water-soluble: B-complex, C; supplement with renal vitamins.

Dialysis effect on medication dosing

Dialysis may clear or concentrate drugs - adjust dose accordingly.

MCT oil use

Alternate energy for fat malabsorption; no bile/pancreas needed.

Low-residue diet

Low fiber, avoids gas-producing & undigested food particles.

High vitamin A avoidance in CKD

Can accumulate to toxic levels; kidneys cannot excrete it well.

Refeeding syndrome

Electrolyte shift (↓ P, Mg, K) after reintroducing nutrition to starved patient.

Potassium restriction

Hyperkalemia, ESRD, urine output <1L/day.

Goal of EN in pancreatitis/IBD/SBS

Maintain gut function, reduce infection, cheaper than TPN.

Glutamine use in GI disorders

Supports enterocyte healing, reduces gut permeability.

Signs of fat malabsorption

Steatorrhea, weight loss, vitamin deficiency (A/D/E/K).

Top complications of cirrhosis

Ascites, encephalopathy, varices, steatorrhea, vitamin deficiencies.

Role of erythropoietin

Stimulates red blood cell production; produced by kidneys.

Hyperphosphatemia in CKD

Decreased renal excretion of phosphate.

Symptoms of hyperphosphatemia

Itching, joint pain, muscle cramps, vascular calcification.

Oliguria

Urine output <500 mL/day.

Anuria

Urine output <50 mL/day.

Urine output

<50 mL/day.

Fluid restriction in dialysis patients

Based on urine output and weight gain between sessions.

Phosphate binder

Medication that binds dietary phosphorus to prevent absorption.

Protein recommendation for PD patient with peritonitis

May need >1.3 g/kg due to losses in dialysate.

BUN elevation in CKD

Decreased clearance by kidneys, protein catabolism, GI bleeding.

Vitamin D supplementation in CKD

Active form (calcitriol) is not produced by damaged kidneys.

High-phosphorus beverages

Cola, beer, chocolate milk.

Metabolic acidosis

Low blood pH due to kidney's inability to excrete hydrogen ions.

Management of metabolic acidosis in CKD

Sodium bicarbonate supplements, adequate protein.

Sodium intake recommendation for CKD

<2.4 grams/day.

Potassium intake goal for hyperkalemia in CKD

<2-3 grams/day.

Fiber type for constipation

Insoluble fiber.

Fiber type for diarrhea

Soluble fiber (pectin, oats).

Ileostomy

Surgical opening in the ileum to remove stool.

Colostomy

Surgical opening in the colon to remove stool.

Foods that increase ostomy odor

Onions, eggs, fish, asparagus.

Foods that reduce ostomy odor

Yogurt, parsley, buttermilk.

Nutrients lost in ostomy patients

B12, fat-soluble vitamins, fluids, sodium.

Wernicke's encephalopathy

Thiamin deficiency, often in ALD.

Role of zinc in CKD

Supports taste sensation and immune function.

Nutrient deficiency common with steatorrhea

Vitamin A, D, E, and K deficiency.