W6 Case Studies Flashcards
Define AKI
decline in renal excretory function over hours or days that can result in failure to maintain fluid, electrolyte and acid-base homeostasis
Parameters:
(1)Creatinine rise of 26 micromol or more within 48 hours
/ Creatinine rise of 50 - 99% from baseline within 7 days
(2) 100-199%) creatinine /7d or urine output <0.5mL/ 12hr+
(3) 200% creat. increase withi 7 days
Define Oliguria
Oligura - reduced urine output < 400mls/24hours
What drugs to cease in AKI
BISOPROLOL
RAMIPRIL
FUROI
IBUPROFEN
Pre-Renal Causes of AKI
Volume depletion
⇩CO
⇩renovasc. blood flow
⇩peripheral vasc resistance
Intrinsic Causes of AKI
Acute interstitial nephritis
Vasculitis
Acute Glomerulonephritis
Post-renal Causes of AKI
Obstruction
Spinal cord disease/injury
Drug effects on the glomerulus
1) Prostaglandins dilate afferent to maintain glomerular perfusion. NSAIDs BLOCK this = constriction. = ⇩perfusion
2) Ang. II constricts efferents if renal perfusion is low so BLOCK ANG. II lead to fall in GFR d/t NSAID
Suitable drugs in AKI
- paracetamol
- weak opiod = codeine phosphate or tramadol
normal range of K+
blood potassium level is 3.6 to 5.2 millimoles per liter (mmol/L).
Hyperkalaemia features on ECG
tall tented t waves
shortened QT interval
and ST-segment depression
principles of hyperkalaemia management
PROTECT HEART = calcium salts (calcium chloride / calcium gluconate) if 6-6.4mmol/L of K+
SHIFT K INTO CELLS = salbutamol; insulin and dextrose
(6-6.4mmol of K+)
REMOVE K FROM BODY = calcium resonium,
(initial milkd 5.5-5.9) or DIALYSIS
MONITOR K AND GLC
PREVENT REOCCURRENCE
You are on night shift and called to the ward to see Mrs C because she is feeling breathless and desaturated.
NEWS = 8 RR 24/min Sats 96% (4 litres) HR 105bpm BP 170/98 mmHg Temp 37.5°C Alert Urine output < 30mls/hour Mrs C had been admitted with acute kidney injury and has been receiving IV fluids.
What do you do?
ABCDE
Fluid assessment
Review output - Is she catheterised? Is the catheter working? Any urine in bladder?
ABG
ECG
Chest x-ray
Complications of AKI
Pulmonary oedema picture, fluid retention, JVP, crackles
(1)
> stop fluids, furosi, monitor output, urgent ultrasound to exclude obstruction
> review soon 1hr
(2)
> dialysis
Indications for acute renal replacement therapy.
Persistent hyperkalaemia resistant to medical therapy
Symptoms or complications of uraemia
Refractory fluid overload and pulmonary oedema
Severe metabolic acidosis
Significance of cyclical MicroHaemut. with periods
Suggestive of endometriosis
Significant travel history for MH
Areas endemic with Schistosoma haematobium or TB
52 male attends GP for right flank pain
No history of UTIs
History of obesity and T2DM
Stopped smoking a year ago
No family history of renal problems
Apyrexial, BP 150/92mmHg
Prostatic examination, digital rectal examination: some prostatic enlargement, smooth and no tenderness or nodularity
Urinalysis: blood ++ only
Urine protein creatinine ratio is 18mg/mmol (<20mg/mmol)
Urine microsocopy: no evidence of dysmorphic RBCs
Cause of MH? Next steps?
Non-glomerular source
CT urogram
36 male offshore Oil and Gas worker was found to have non-visible haematuria on 2 consecutive urine samples
He has no significant past medical history
He reports having episodes of sore throat in the past and on one occasion having frank blood in the urine (when he was 16)
No family history of kidney disease
Blood pressure has been elevated recently at 158/100mmHg
What are next investigations?
Urine protein creatinine ratio
U&Es
ANA / ANCA / C3-C4 / immunoglobulins
Indications for renal biopsy
Haematuria (in the absence of infections or urological abnormalities) often in the presence of other markers of kidney injury e.g. significant proteinuria, hypertension, rising creatinine or immunological markers
Proteinuria of more than 1 g/day
Unexplained renal impairment
To investigate renal involvement in systemic diseases
A previously fit and healthy 52-year old man presents with bilateral lower limb oedema (acute onset), fatigue and frothy urine. He is a non-smoker and drinks c. 21 units alcohol/week. He works as an accountant. Urine dip shows 4+ protein.
and apt investigations
Nephrotic Syndrome, typical picture
> urine p:c / albumin:creatinine + 24hr
> bloods albumin
> definitive: biopsy for light microscopy/ immunifluorescence / electron microscopy
features that characterise nephrotic syndrome?
Proteinuria (> 3.5g/24hours)
Hypoalbuminaemia (< 30g/L)
Peripheral oedema
+Hyperlipidaemia and thrombosis (usually VTE) are also frequently seen.
Primary and 2º Causes of Nephrotic Syndrome
Minimal Change Disease
Focal Segmental Glomerulosclerosis
Membranous Nephropathy
2º
Diabetic Nephropathy
Systemic Lupus Erythematosis (SLE)
Amyloidosis
Typical picture of nephritic syndrome
presence of AKI, increased BP and an active urine sediment of red cells/red cell casts
Tests for nephritic syndrome
ANCA esp with rapid progressive glomerulonephritis with AKI
Key marker in membranous nephropathy
Anti-PLA2R, correlation with disease activity thus good monitoring tool.
Receptor expressed on podocytes.
Complication of membranous nephropathy
Hypercoagulability/thrombosis (due to urinary loss of anticoagulant proteins such as antithrombin II and plasminogen, as well as an increase in clotting factors). Also, immobility and abnormal endothelial function contribute.
Infection e.g. Beta-haemolytic streptococcal cellulitis and pneumococcal peritonitis
AKI
Progressive CKD
Mgmt approach to idiopathic membranous nephropathy
conservative unless symptomatic or 8g+ proteinuria
> BP control, ACEi, diuretics, statins
High risk of complications
> imm. suppr. Rx
Hallmarks of Minimal Change Disease
Oedema: periorbital + peripheral
Wt gain
Often childhood
> steroid trial without biopsy in children
