Metabol 2) Renal function tests and acid-base metabolism Flashcards
What needs to be accounted for when estimating GFR?
Muscle mass outliers
Pregnancy
Obesity
What can cause hyperkalaemia?
Decreased renal excretion
Shift of intracellular potassium - insulin lack, acidosis, tissue catabolism
What un-measured anions need to be considered?
Ketones
Lactate
Ethylene glycol
Salicylate
What influences sodium levels?
Water retention - AKI
Excessive water intake - polydipsia
Artefactual - high glucose
What causes should be considered if AKI?
Obstruction, hydration , infection
Drugs - ACEi, ARB, NSAIDs, diuretics, metformin
What are some electrolyte complications of AKI?
Raised K+
Raised H+
Raised PO4
What initial assessments should be done for AKI?
Volume status
Serum K, HCO3, PO4, calcium, albumin
Serum uric acid, magnesium
FBC
How can glomerular disease manifest?
Asymptomatic urinary abnormalities
AKI
End-stage kidney disease
What are the clinical manifestations of glomerular disease?
Haematuria, albuminuria, proteinuria
Kidney insufficiency
Hypertension
Oedema
How is nephrotic syndrome defined?
Heavy albuminuria ACR>250mg/mol Low serum albumin <30g/L Peripheral oedema - low oncotic pressure - kidney sodium retention
Describe creatine kinase levels in different individuals
Levels related to muscle mass
Lower levels in women and children
Black africans have greater muscle mass
Affected by physical exertion
What are kidney stones composed of?
Calcium oxalate Calcium phosphate Uric acid Ammonium Cysteine Xanthine
What investigations should be done for kidney stones?
Fluid intake Radiology Urine culture Serum Na, K, Cl, HCO3, creatinine, Ca, albumin, PO4, alkaline phosphatase, uric acid, vitamin D, PTH Urine
How can distal renal tubular acidosis be diagnosed?
Low serum K Metabolic acidosis with normal anion gap Increased serum Cl Inappropriately alkaline urine Clinical context Urine pH, citrate, bicarbonate Urine acidification test
How is renal tubular acidosis treated?
Potassium citrate
Correct acidosis
