Uremic Syndrome Flashcards
What is uremia?
Symptomatic renal failure in which there is multiple organ dysfxn and biochemical abnormalities. Need transplant or dialysis
What is chronic kidney disease?
Slowly progressive decline in GFR. Usually asymptomatic until GFR <20-25ml/min
Effect of uremia on the GI system
- Loss of appetite (eat less protein)
- Altered taste, metallic due to ammonia in saliva
- Mouth ulcers due to mucosal irritation from ammonia
- Uremic fetor: bacterial conversion of urea to ammonium in oral cavity
- Esophagitis and motility problems-alteration in peristalsis
- GI bleeding: superficial mucosal abnormalities, angiodysplasia of the GI tract, peptic ulcer
- Diverticular disease and constipation
CKD Anemia
One of the main laboratory manifestations of renal failure
- usually normochromic normocytic
- Low reticulocyte count for degree of anemia (hypoproliferative)
- Normal bone marrow
When does hematocrit start to fall in most pts with CRF?
When creatinine clearance reaches 30-35ml/min
Primary causes of anemia ni CKD?
- Decreased production of EPO
- Shortened erythrocyte life span
- Inhibitors of erythropoiesis accumulating in uremia
Consequences of anemia in CKD?
- Progressive reduction in activity and energy level and of exercise tolerance
- LV dilation and diastolic dysfxn
- Increased hospitalizations
- Deterioration of cognitive fxn
- Intractable itching (elevated phos)
- Impairment of sexual fxn
Aggravating causes of anemia in CKD?
- Factors hampering EPO production/effect
- B12/folic acid/iron def
- Blood loss (GI: inflammation, Dialysis related)
- Bone marrow fibrosis due to hyperparathy
- Reticuloendothelial blockade from infections, cancer and inflammatory states
- Myelofibrosis or aluminum accumulation - Disease causing both anemia and renal failure
Treatment of anemia in CKD?
- Blood transfusion
- Iron therapy (key, must be repleted for EPO to work)
- Recombinant human EPO
- Darbepoetin alfa
Describe the hematopoietic system in CKD
- Bleeding tendency, prolonged bleeding time
- Platelets: main determinant of altered bleeding in uremia (platelet aggregation dysfxn)
- Dialysis of uremic serum appears to remove “some compound” that causes the binding defect (not much is lost here)
Why is there increased bleeding in CKD?
- Inc NO inhibits platelet fxn
- Inc cAMP due to elevated PTH
- Abn fxn of vascular endothelial wall
Treatment for uremic bleeding disorders
- EPO
- DDAVP (stimulates von willebrand factor and increases platelet glycoprotein expression)–>tachyphylaxis
- Conjugated estrogens
- Transfusions of cryoprecipitate
- Dialysis to remove “toxins”
Risk factors unique to CKD that inc risk of CVD
- Anemia
- Increased homocysteine
- Thrombogenic factors
- Obesity
- intake of Ca (leads to deposition in arteries)
- Hyperparathyroidism
- Uremic toxins
- inflammatory state
- Less aggressively treated with beta blockers and statins
- Accelerated arterial calcification, endothelial dysfxn, art stiffness, prothrombotic factors, abn apolipoprotein levels
- Increased TGs and LDL with dec in HDL
- Increased APO1
Sexual dysfxn in CKD
happens
Pregnancy in CKD
Rare and dangerous, depends on degree of functional impairment (note return in fertility 1-2mo after transplant)
Dangers with pregnancy in ppl with CKD
- Preeclampsia
- Fetal growth retardation
- Prematurity
- Low birth weight
- Congenital anomalies
CKD and mineral/bone disorder
- Vit D def (kidney activates)
- No reabs of phosphorus
- Leads to decrease in calcium, elevated phosphorus, low activated vit D and high PTH and elevated FGF-23
- Causes abnormalities of bone turnover, mineralization, volume, linear growth and strength
- Vascular and soft tissue calcification (precipitates as calcium phosphate)
FGF-23
- Produced by osteocytes and osteoblasts
- Acts upon kidney to cause phosphaturia
- Decreases the production of vit D by suppressing 1 alpha hydroxylase leading to hyperparathy
Clinical signs and symptoms of secondary hyperparathy
- Bone pain
- Spontaneous fractures
- Periarthritis/arthritis
- Spontaneous tendon rupture
- Muscle weakness/myopathy
- Skeletal deformities
- Growth retardation
Mineral and bone disease treatment
- Correct vit D def
- Diminish intestinal phosphate abs by low phosphate diet and phosph binders
- Treat elevated PTH
