Acute urinary problems Flashcards
What two things are measured in AKI and help to define AKI? What is the main clinical clue?
Serum urea and creatinine
REDUCED URINE OUTPUT is the main clinical clue - consider AKI in anyone with reduced urine output
How is AKI staged and what are the stages?
KDIGO staging
- Creatinine increased by >26umol or 1.5X baseline PLUS urine output <0.5mL/kg/h for 6 consecutive hours
- Creatinine increase by 2-2.9X baseline PLUS urine output <0.5mL/kg/h for 12 consecutive hours
- Creatinine increase >3X baseline PLUS urine output of <0.3L/kg/hr for >24h or anuria for 24h
How is it most useful to split up the major causes of AKI?
Into pre-renal, intra-renal or post-renal causes
What are the most common pre-renal causes of AKI?
Nearly always due to HYPOPERFUSION of the kidney (these are very common reasons for AKI to develop)
- Hypovolaemia
- Sepsis
- Renal artery stenosis
What are some common intra-renal causes of AKI?
Acute tubular necrosis - often as result of pre-renal damage or nephrotoxic drug (e.g. contrast medium, NSAIDs)
Glomerular damage (common in autoimmune disease e.g. SLE or HSP)
Interstitial damage (Due to drugs, infiltration, lymphoma)
Vascular (vasculitis, malignant hypertension, thrombus(
What are some common post-renal causes of AKI?
Renal stones, luminal malignancies or extrinsic compression (e.g. from tumour or retroperitoneal fibrosis)
What are some risk factors for developing AKI?
Age >75, CKD, Cardiac failure, peripheral vascular disease, Diabetes, chronic liver disease, drugs (always look for newly started medications), sepsis, poor fluid intake
How should you investigate someone if you suspect they’ve got an AKI?
Do a bedside investigation looking for rashes, fevers or any examples of the patient being systemically unwell
LOOK FOR: palpable bladder (?retention), palpable kidneys or renal bruits
URINE DIP
BLOODS; FBC, U&E (look for K+), LFT, CRP, Clotting, CK, ABG
IMAGING: Renal USS and bladder scan
How should you initially manage a patient with AKI?
Assess volume status and give them fluids if necessary (0.9% NaCl good - avoid any fluids with potassium)
STOP NEPHROTOXIC DRUGS
Search for and treat underlying cause and refer to nephrology if necessary
What common drugs are nephrotoxic?
ACE-inhibitors Diuretics Intravenous contrast Antibiotics - gentamicin and nitrofurantoin Metformin Opioids NSAIDs Decrease BP (B-blockers) Lithium
A DIAMOND + Li
In an elderly patient that comes in confused, what two urinary problems should you always consider?
UTI
ACUTE URINARY RETENTION
In a patient who is in acute urinary retention what can you expect to find on examination?
An enlarged, tender bladder that is dull to percussion
Who is acute urinary retention more common in and why?
MEN
Due to prostatic hypertrophy
Also common post-operatively and due to urethral stricture
What are some common causes of acute urinary retention in women?
Retroverted gravid uterus
Atrophic urethritis
MS (multiple sclerosis)
What are some relevant investigations in urinary retention?
ALWAYS SUSPECT SPINAL PATHOLOGY
Perform peripheral nerve assessment of the lower limb, also perform a PR and assess anal tone
When performing a PR in men also take the opportunity to assess the prostate
How should acute urinary retention be managed?
Urgent bladder decompression as long as there is no contraindication
Urethral catheterisation or consider supra-pubic if urethral not possible
Once urine has been passed then DIP IT for infection and treat that
How will renal colic present?
Intermittent flank or loin pain that might also travel down to the groin
SEVERE PAIN that comes and goes in waves - this pattern of pain is due to ureteric peristalsis
Might also have urinary symptoms of:
- Anuria, dysuria, increased frequency, urgency, suprapubic tenderness, changes in smell or colour of urine, haematuria, sweating, fever, N&V
What is a common cause of renal colic?
KIDNEY STONES (Sweaty, N&V, and excruciating pain will predominate)
How should you investigate someone with renal colic pain?
KUB USS Urine dip - blood leucocytes Pregnancy test in women CT Bloods: FBC, U&E, WCC, CRP
How should someone with renal colic be managed initially?
Painkillers (might need IV)
FLUIDS - really important to keep patient hydrated.
Shock therapy can break down stones to make them easier to pass
How will testicular torsion present?
What will appear like on examination?
Sudden onset SEVERE PAIN in the testicles, upper thigh, groin or lower abdomen
Vomiting
O/E: Red, Swollen, tender testis, ABSENCE of cremasteric reflex, might lie more horizontally than vertically
Who is testicular torsion most common in?
Boys in neonatal period and then again between the ages of 11-30 (peak during puberty)
How should this be investigated?
It shouldn’t. If you suspect torsion you need to contact uro-surgery immediately because it is time sensitive
How do we define a UTI?
Sometimes by the symptoms but sometimes there are none (ASYMPTOMATIC BACTERURIA) bactria >10^5 in urine
- Sometimes asx bacteriuria need treating and sometimes not (PREGNANT WOMEN NEED TREATMENT)
What are some symptoms of UTI?
Urgency, Frequency, Changes in colour or smell to urine, dysuria, supra-pubic tenderness, blood in urine, sweating, fever, N&V
What sort of symptoms would make you concerned that the LUTI had become an UUTI?
Fever, rigors, sweating, malaise, anorexia, loin/back pain and vomiting
MORE SYSTEMIC SYMPTOMS OF UNWELL
What is the most common cause of UTI?
Gram negative bacteria from the gut (usually E.coli) but should always do a culture to make sure you’re treating to right bug
How do we investigate a UTI
Urine dip (look for nitrites - sensitive, leucocytes, protein, blood) Urine microscopy and culture
Initial management of UTI
If Uncomplicated: 3-6 day course of trimethoprim or nitrofurantoin and advice about hydration
Asx Bacteriuria in pregnant women give amoxicillin
MEN should be given 2 weeks of ciprofloxacin, trimethoprim or co-amoxiclav and followed up
IF CATHETER only treat if symptomatic - 7 days of ciprofloxacin or co-amoxiclav
