Kidney Flashcards
(50 cards)
What drugs are safe in AKI
Paracetamol Warfarin Statins Aspirin Clopidogrel BB
What drugs to stop in AKI
NSAIDs ACEi/ARBs Metformin Diuretics Gentamicin Amphotericin Lithium Digoxin
What is focal segmental glomerulosclerosis
Affects part (segmental) or some (focal) glomeruli of nephron. Foot processes of podocytes damaged, proteinuria. Proteins, lipids trapped, build up in glomeruli, hyalinosis, scar tissue > glomerulosclerosis.
Mesangial matrix expansion + capil loop collapse.
What is membranoproliferative/mesangio capillary GN
Inflam of GBM, mesangium, ↓kidney function.
IC mediated: circulating IC deposit in kidney, activate complement. Hep C, SLE, monoclonal gammopathies.
Complement mediated: less common, persistent activation of alternative complement pathway eg C3 nephritic factor.
What is membranous GN?
Inflam of GBM, subendothelium IC deposits (between podocytes + GBM), ↑permeability,
Autoantibodies target M type phospholipase A2 receptor + neural endopeptidase on GBM
Complement activated, damage to podocytes mesangial cells work to remove debris.
Light microscopy: diffuse thickening of GBM
Electron microscopy: spike + dome, GBM matrix on top of subendothelial deposits, podocyte effacement
Minimal change disease
Most common nephrotic synd in kids
Podocyte effacement > lose barrier function > albumin permeates, bigger proteins can’t get through (selective)
Summary of amyloidosis
Abnormal amyloid fibrils build up + damage tissues. AL (light chain) eg myeloma, huge no of light chain produced some misfolded + deposit in tissue. AA (serum amyloid A) normal protein that is acute phase reaction, in inflam conditions eg RA, IBD, lot of SAA in blood, accumulate in tissues.
Hepatosplenomeg JVP distension Large tongue Periorbital purpura Unexplained WL, N/C/D Abdo cramps Fatigue Dyspnoea OE Claudication Submandibular gland enlargement Light headed/ orthostatic hypotension Shoulder pad sign: periarticular infiltration with amyloid, pseudohypertrophy, enlarged musculature of shoulder/ hip girdles Diffuse muscular weakness Proteinuria
Tinel’s/Phalen’s sign
Serum/urine immunofixation: pos, presence of monoclonal protein
Immunoglobulin free light chain assay: abnormal kappa to lambda ratio.
Bone marrow biopsy: clonal plasma cells
Biopsy: Congo red stain, deposits pink, green birefringement under polarised light.
LM: eosinophilic deposits in mesangium, cap loops, arteriolar walls.
Serum amyloid P scintigraphy: uptake at sites of amyloid deposition
↑ALP if hepatic amyloid
↓albumin
Eprodisate: inhibits deposits in tissues
Myeloablative chemo
Dexamethasone
Post strep GN
Wks after group A β haemolytic strep
T3 hypersensitivity, IC deposition.
Rapidly progressive GN
Renal failure
Good pasture syndrome
Ant-GBM antibody disease, damage BM in lungs, kidneys
ANCA pos
IgA nephropathy
Berger’s disease.
Abnormal post translational mod of IgA, IgG binds to IgA IC deposited in mesangium. T3 hypersensitivity, alternative complement activated, cytokines released, macrophages migrate to kidney, glomerular injury, RBC leak into urine.
1-2 days after URTI
Rapidly progressive GN
Inflam of kidney’s glomeruli, crescent shaped prolif of cells in Bowman’s capsule
Crescent aggregate of macrophages + epithelial cells in Bowman’s space.
Anti GBM:Goodpasture
IC: post-step GN, SLE, IgA neph, Henoch—Schoenlein purpura.
Pauci immune: ANCA, C-ANCA > Wegener’s. PANCA > microscopic polyangiitis, Churg Strauss.
Renal failure within wks/mnths
Alport syndrome
Defect in gene coding for T4 collagen > abnormal BM of kidney glomerulus, eye, cochlea
Appear childhood/ adolescence
Renal: progressive renal insuff, HTN, GN. Microscopic/ gross haematuria, proteinuria
Eye: corneal abrasions, lens opacity, ocular pain, myopia, visual disturbance cataracts.
Ear: initial high freq/tone hearing loss, loss of normal speech, bilat
Fatigue/ breathlessness/ periph oedema: renal failure/ anaemia
Learning disability
Growth retardation
Retinitis pigmentosa
ACEi, ARB: prevent progression to kidney failure
Dialysis
Kidney transplant
Replacement of lens in ant lenticonus
Monitor renal disease
Hearing loss may benefit from hearing aids.
Causes of hypernatraemia
Extrarenal water loss: skin (sweat), GI (N/V)
Hypothalamic lesion: ↓ADH > dilute water loss as water not reabsorbed. Central DI
Renal water loss: nephrogenic DI
osmotic diuresis e.g. hyperosmolar non-ketotic diabetic coma
excess IV saline
Sx of hypernatraemia
FRIED SALT F: fever R: restless, anxious I: ↑fluid retention, HTN E: oedema D: ↓UO, dry mouth S: skin flushed A: agitated L: low grade fever T: thirst
Tx of hypernatraemia
Hypernatraemia should be corrected with great caution. Although brain tissue can lose sodium and potassium rapidly, lowering of other osmolytes (and importantly water) occurs at a slower rate, predisposing to cerebral oedema, resulting in seizures, coma and death
it is generally accepted that a rate of no greater than 0.5 mmol/hour correction is appropriate
Causes of hyponatraemia
caused by water excess or sodium depletion
pseudohyponatraemia - hyperlipidaemia (^ in serum volume) or taking blood from drip arm
need urinary sodium and osmolarity levels to make diagnosis
urinary sodium > 20 mmol/l Sodium depletion, renal loss (patient often hypovolaemic) diuretics: thiazides, loop diuretics Addison's disease diuretic stage of renal failure
Patient often euvolaemic
SIADH (urine osmolality > 500 mmol/kg)
hypothyroidism
urinary sodium <20 mmol/l
Sodium depletion, extra-renal loss
diarrhoea, vomiting, sweating
burns, adenoma of rectum
Water excess (patient often hypervolaemic and oedematous)
secondary hyperaldosteronism: heart failure, liver cirrhosis
nephrotic syndrome
IV dextrose
psychogenic polydipsia
Sx of hyponatraemia
SALT LOSS S: stupor/coma A: anorexia (N/V) L: lethargy T: tendon reflex ↓ L: limp muscles (weak) O: orthostatic hypotension S: seizures/ headache S: stomach cramps
Causes of hyperkalaemia
acute kidney injury drugs*: potassium sparing diuretics, ACE inhibitors, angiotensin 2 receptor blockers, spironolactone, ciclosporin, heparin** metabolic acidosis Addison's disease rhabdomyolysis massive blood transfusion
Sx of hyperkalaemia
M: muscle weakness U: urine, oliguria, anuria R: resp distress D: ↓cardiac contractility E: ECG changes R: reflexes, hyperreflexia, areflex↓K ia (flaccid)
ECG: prolonged PR, tall, peaked (tented T waves with narrow base), short QT, depressed ST, sinuisoidal
Management of hyperkalaemia
10mL 10% Ca gluconate: stabilise myocardial cells
Insulin with dextrose + β-2 agonist (salbutamol): ↑K into cells
Kayexalate: bind K, ↓K absorbed from GIT
Loop diuretics, Ca resonium (enemas more effective than oral as K is secreted by rectum), dialysis: ↑K excretion in kidneys.
Sx of hypokalaemia
A SIC WALT A = alkalosis S = shallow resps I = irratibility C = confusion + drowsy W = weakness + fatigue A = arrhythmias L = lethargy T = thready pulse
ECG: flattened/ inverted T waves, U waves, ST depression, prolonged PR, prolonged QT
Causes of hypokalaemia
Hypokalaemia with hypertension: Cushing's syndrome Conn's syndrome (primary hyperaldosteronism) Liddle's syndrome 11-beta hydroxylase deficiency*
Hypokalaemia without hypertension: diuretics GI loss (e.g. Diarrhoea, vomiting) renal tubular acidosis (type 1 and 2**) Bartter's syndrome Gitelman syndrome
Management of hypokalaemia
Replenish with K supplementation
If mild oral sando-K, if severe IV K
Mg replacement, ↓K often hard to correct until Mg levels normalised.
If diuretic therapy: K sparing diuretics
Causes of hypercalcaemia
- Primary hyperparathyroidism: commonest cause in non-hospitalised patients
- Malignancy: the commonest cause in hospitalised patients. This may be due to number of processes, including;
PTHrP from the tumour e.g. squamous cell lung cancer
bone metastases
myeloma,: due primarily to increased osteoclastic bone resorption caused by local cytokines (e.g. IL-1, tumour necrosis factor) released by the myeloma cells
Other causes include sarcoidosis* vitamin D intoxication acromegaly thyrotoxicosis Milk-alkali syndrome drugs: thiazides, calcium containing antacids dehydration Addison's disease Paget's disease of the bone
