Renal conditions Flashcards
Renal Colic - Description
Renal stones (calculi) made of crystal aggregates form in collecting ducts and then deposited anywhere from renal pelvis to urethra
Renal Colic - Epidemiology
- More males
- 10% lifetime risk
- More in the Middle East
Renal Colic - Pathology
- Solutes in urine become too concentrated → supersaturated → solvent precipitates → crystals form
- Occurs when there is an increase in solute or a decrease in solvent (dehydration)
- Crystals make stones which cause obstruction → hydronephrosis (obstruction and dilation of renal pelvis → lasting kidney damage)
- Stones are made of: calcium oxalate (most common, in acidic urine), calcium phosphate (in alkali urine), calcium carbonate, uric acid, crystine, drug precipitants
- Stones are most commonly found in pelviureteric junction (most common), pelvic brim, vesicoureteric junction
Renal Colic - Types
- Upper urinary tract - renal stones, ureteric stones
- Lower urinary tract - bladder stones, prostatic stones, urethral stones
Renal Colic - Causes (7)
- Anatomical - congenital (horseshoe, duplex, pelviureteric junction obstruction, spina bifida) and acquired (obstruction, trauma, reflux)
- Urinary - dehydration, too much solutes
- Infection - UTIs with organisms that produce urease (Proteus, Klebsiella, Pseudomonas) produce specific types of stones called staghorn calculus
- Hypercalciuria - increased urinary calcium excretion (caused by hyperparathyroidism - most common, hypercalcaemia, eating too much calcium, prolonged immobilisation - bone reabsorption)
- Hyperoxaluria - increased oxalate means more clacium oxalate (eating too much oxalate, malabsorption, autosomal recessive enzyme deficiency)
- Uric Acid Stones - patients with ileostomies as they loose more bicarbonate so have acid urine so uric acid is more soluble
- Cystine stones - caused by an autosomal recessive condition, cystinuria
Renal Colic - Prevention (6)
- Reduce dietary salt / sodium
- Normal dairy intake
- Healthy protein intake (50-100g/day)
- Lose weight
- Active lifestyle
- Stop smoking
Renal Colic - Risk Factors (9)
- Anatomical abnormalities
- Hypercalciuria
- Hypercalcaemia
- Hyperparathyroidism
- Family history
- Hypertension
- Gout
- Immobilisation
- Dehydration
Renal Colic - Differential Diagnosis (9)
- Ruptured AAA
- Diverticulitis
- Appendicitis
- Pylonephritis
- Acute pancreatitis
- Ectopic pregnancy
- Ovarian cyst
- Ovarian torsion
- Testicular torsion
Renal Colic - Symptoms (6)
- Asymptomatic
- Loin pain, rapid onset, unable to get comfy, radiates to groin, N&V
- UTI symptoms - dysuria (painful urinating), strangury (burining urinating), urgency, frequency
- Shivering
- Recurrent UTIs
- Bladder distension
Renal Colic - Investigations (6)
- History - excess Vit D consumption leads to hypercalcaemia, excess rhubarb or tea leads to high oxalate
- X-Ray KUB (kidney, urethre, bladder) - first line
- Non-contrast CT KUB - gold standard
- Ultrasound - sensitive for hydronephrosis, good for pregnant or youth
- Urine dipstick - blood traces
- Bloods - FBC, U&E, Calcium, Uric acid, Creatinine
Renal Colic - Treatment (9)
- Ureteric stones
- Analgesia - diclofenac IV 75mg
- Anti-emetics - metoclopramide
- Allow 2 weeks for it to pass
- Drainage if septic
- ESWL (Extracorpeal Shock Wave Lithotripsy) - non invasive procedure breaks down stones, use if <1cm
- Kidney stones
- Analgesia - Diclofenac
- Anti-emetics - Metoclopramide
- ESWL - for stones 1-2cm
- Surgical - uteroscopy, percutaneous nephrolithotomy, nephrectomy
Renal Colic - Complications (3)
- Small stones migrate to ureter
- Large stones occlude calyces or uteric pelvic junction
- Chronic damage especially if it gets infected
AKI - Description
Abrupt deterioration (hours-days) in renal function (raised serum urea and creatinine) due to a rapid decline in GFR leading to a failure to maintain fluid, electrolyte and acid-base homeostasis. Usually reversible
AKI - Criteria for Diagnosis
- Creatinine increased >26 micromol/L in 48 hours
- Creatinine increased >50%
- Urine output <o.5ml/kg/hr for more than 6 hours
AKI - Epidemiology
- Associated with diarrhoea, haematuria, haemoptysis, hypotension, urine retention
- Common in elderly
- 25% with sepsis and 50% with septic shock have AKI
AKI - Causes
- Pre-renal - reduced blood flow to kidney leading to reduced GFR
- Shock, hypovolaemia, hypotension, Renal artery thrombosis, sepsis, renal hypoperfusion
- Renal - kidney can’t filter blood properly, cells damaged so reabsorption and secretion impaired
- Acute tubular necrosis, Nephrotoxins, Glomerulonephritis, Acute interstitial nephritis, Infection, Vasculitis, Malignant hypertension, Autoimmune disease
- Post-renal - blockage of kidney reducing outflow
- BPH, Kidney stones, Cancer, Blood clot
AKI - Risk Factors (8)
- > 75
- DM
- HF
- Sepsis
- PVD
- Family history
- Drugs
- Dehydration
AKI - Symptoms (11)
- Asymptomatic in early stages
- Oliguria (decreased urine output)
- Anuria (no urine output)
- Ddehydration
- N&V
- Tremor, weakness, fatigue, confusion
- Breathlessness (anaemia and pulmonary oedema from volume overload)
- Tachycardia
- Peripheral oedema (from hypertension)
- Poor tissue turgor
- Postural hypotension (dehydration)
AKI - Investigations (5)
- Urine dipstick - glomerulonephritis suggested by haematuria and proteinuria
- Bloods - Anaemia and high ESR suggest myeloma or vasculitis
- Renal ultrasound - shows obstruction, small kidney indicates CKD
- Monitor urine output
- KUB XR and non-contrast CT
AKI - Complication
Hyperkalaemia - when kidneys fail they go into cardiac arrest
AKI - Treatment (4)
- Treat underlying cause - pre-renal (fluids, antibiotics), post-renal (catheteris, cystoscopy)
- Stop nephrotoxic drugs - NSAIDs (aspirin, diclofenac, ibuprofen), ACEi (Ramipril), Gentamicin, Amphotericin
- Treat complications - hyperkalaemia, pulmonary oedema, uraemia, acidaemia
- Dialysis
CKD - Definition
Long standing, usually progressive abnormality of the kidney or a reduction of GFR to <60ml/min/1.73m2 for >3 months
CKD - Epidemiology
- 6-11% incidence
- Risk increases with age
- More females
- Highest mortality from cardiac complications
CKD - Classification/staging
- Stage 1: >90ml/min - Normal GFR with evidence of renal damage
- Stage 2: 60-89 - Slight decrease GFR with evidence of renal damage
- Stage 3A: 45-59 - Moderate GFR decrease with or without evidence of renal damage
- Stage 3B: 30-44 - Moderate GFR decrease with or without evidence of renal damage
- Stage 4: 15-29 - Severe GFR decrease with or without evidence of renal damage
- Stage 5: <15 - Established renal failure
CKD - Pathology
- Progression of end-stage kidney disease (ESRF) with varying speed of decline
- Many nephrons are failed so burden of filtration goes to functioning nephrons which experience hyperfiltration (increased flow per nephron as blood flow remains the same) → glomerular hypertrophy and reduced arteriolar resistance
- Stress means increased failure of functioning nephrons and cycle continues
CKD - Pathology of bone disease
Increased renal phosphate and reduced 1,25-dihydroxyvitamin D → reduced serum calcium → compensatory increase PTH → skeletal decalcification
CKD - Pathology of Anaemia
reduced erythropoietin production → less RBCs → anaemia. reduced production and excretion of hepcidin builds up and inhibits iron absorption → anaemia
CKD - Pathology of Hyperkalaemia
less potassium excretion → build up in blood
CKD - Pathology of CVD
decreased filtration → renin release → increase BP → cardiomyopathy, pericarditis (uraemia), bleeding (urea stops platelet binding)
CKD - Causes (7)
- Hypertension - walls thicken to withstand pressure → narrow lumen → less blood and O2 to kidney → ischaemic injury. Immune cells release TGF-B1 in damaged glomerulus → mesangial cells regress to immature mesangioblast and secrete extracellular matrix → glomerulosclerosis
- DM - Excess glucose sticks to proteins making efferent arterioles stiff and narrow → obstruction for blood leaving glomerulus → hyperfiltration → supportive mesagnial cells secrete structural matrix → increased size of glomerulus → glomerulosclerosis
- Glomerular disease - Nephrotic syndrome damages glomerular capillary call and decreases tubular protein reabsorption → renal tubular cell damage → inflammation → fibrosis of proximal tubular cells
- PKD
- SLE (Systemic Lupus Erythematosus
- Obstructive uropathy
- Nephrotoxic drugs
CKD - Risk Factors (9)
- DM
- Hypertension
- Age
- Female
- CVD, IHD, PVD
- SLE
- Family history
- UTIs
- BPH
CKD - Symptoms (11)
- Asymptomatic in early stages
- Urinary - oliguria, haematuria, proteinuria, nocturia, polyuria
- Non-specific - N&V, anorexia, itching, hiccups, lethargy, tremors, convulsions
- Bone disease - osteomalacia, osteoporosis, osteosclerosis
- Anaemia - pallor, lethargy, exertional breathlessness, bruising
- Hyperkalaemia - cardiac arrhythmias/arrest, weakness/paralysis, metabolic acidosis
- CVD - uraemic pericarditis, hypertension, PVD, HF
- Neurological - confusion, coma, fits
- Volume overload - pulmonary oedema, dyspnoea, ankle oedema
- Sexual dysfunction
- Increased skin pigmentation (yellow)
CKD - Investigations (2)
- Ultrasound - bilaterally small kidneys, excludes obstruction
- FBC - anaemia, raised creatinine, phosphate,PTH, K+, renin and urea, decreased Ca2+
CKD - Treatment (7)
- Treat underlying cause
- Manage BP (ABCD) - ACEi, Beta Blocker, Calcium channel blocker, Diuretic
- Statins - if GFR <60
- Lifestyle changes
- Stop nephrotoxic drugs
- Dialysis
- Transplant