Master CPS - Renal/Urology
for MSRA

Core Concepts

**Acute Kidney Injury (AKI):** Sudden and often reversible decline in renal function. Classified into pre-renal (hypoperfusion), intrinsic (parenchymal damage e.g., ATN, GN), and post-renal (obstruction).
**Chronic Kidney Disease (CKD):** Progressive, irreversible decline in kidney function persisting for >3 months, defined by eGFR <60 mL/min/1.73m² or markers of kidney damage (e.g., albuminuria). Stages 1-5.
**Urinary Tract Infection (UTI):** Infection of the urinary tract. Types include cystitis (bladder), pyelonephritis (kidney), prostatitis (prostate). Can be uncomplicated or complicated.
**Nephrolithiasis (Kidney Stones):** Formation of calculi in the urinary tract. Most common type is calcium oxalate. Presents as renal colic.
**Glomerulonephritis (GN):** Inflammation of the glomeruli. Can manifest as Nephritic Syndrome (haematuria, hypertension, oliguria, mild proteinuria) or Nephrotic Syndrome (heavy proteinuria, oedema, hypoalbuminemia, hyperlipidaemia).
**Benign Prostatic Hyperplasia (BPH):** Non-malignant enlargement of the prostate gland, common in older men, leading to Lower Urinary Tract Symptoms (LUTS).
**Obstructive Uropathy:** Blockage of urine flow at any level of the urinary tract, leading to hydronephrosis and potential renal impairment.

Clinical Presentation

• **AKI:** Oliguria/anuria, peripheral oedema, fatigue, nausea/vomiting, altered mental status. History of dehydration, sepsis, nephrotoxic drugs, or recent obstruction.
• **CKD:** Often asymptomatic early. Later: fatigue, pruritus, dyspnoea, reduced appetite, metallic taste, oedema, easy bruising.
• **Cystitis:** Dysuria, increased frequency/urgency, suprapubic pain, haematuria.
• **Pyelonephritis:** Fever, chills, unilateral loin pain, nausea/vomiting, dysuria. May be acutely unwell and septic.
• **Renal Colic (Nephrolithiasis):** Sudden onset, severe, colicky flank pain radiating to groin/testicle/labia, nausea, vomiting, haematuria. Patient is typically restless.
• **Nephritic Syndrome:** Cola-coloured urine (gross haematuria), periorbital oedema, hypertension, oliguria.
• **Nephrotic Syndrome:** Frothy urine, widespread pitting oedema (anasarca), fatigue, weight gain.
• **BPH:** LUTS – Storage symptoms (frequency, urgency, nocturia) and Voiding symptoms (hesitancy, weak/intermittent stream, straining, incomplete emptying).
• **Obstructive Uropathy:** Loin pain (often dull/aching), reduced urine output, palpable bladder, features of AKI/CKD, recurrent UTIs.

Diagnosis (Gold Standard)

**AKI:** Defined by serum creatinine rise (≥26.5 µmol/L in 48h OR ≥1.5x baseline in 7 days OR urine volume <0.5 mL/kg/h for 6h). Identify cause via urinalysis, renal ultrasound (to exclude obstruction), and targeted blood tests. **CKD:** eGFR <60 mL/min/1.73m² for >3 months, OR markers of kidney damage (e.g., albuminuria, haematuria, structural abnormalities) for >3 months. Confirmed by serial eGFRs and Albumin-Creatinine Ratio (ACR). **UTI:** Urine dipstick positive for nitrites and/or leukocyte esterase. Gold standard is urine culture (MSU) for organism identification and sensitivity. **Nephrolithiasis:** Non-contrast CT KUB is the gold standard. Renal ultrasound is useful for initial assessment of hydronephrosis. **Glomerulonephritis:** Renal biopsy is definitive, guiding specific diagnosis and treatment. Serological tests (e.g., ANCA, anti-GBM, C3/C4, ANA) aid in differential diagnosis. **BPH:** Clinical diagnosis based on LUTS, International Prostate Symptom Score (IPSS), and Digital Rectal Examination (DRE). PSA testing may be performed to screen for prostate cancer (if indicated). **Renal Artery Stenosis:** Diagnosed via duplex ultrasound, CT angiography, or MRA.

Management (First Line)

**AKI:** Address underlying cause (e.g., fluid resuscitation for hypovolaemia, cease nephrotoxic drugs, relieve obstruction). Monitor fluid balance and electrolytes closely. Dialysis if severe complications (e.g., hyperkalaemia, pulmonary oedema, uremic encephalopathy). **CKD:** Manage complications: BP control (<130/80 mmHg, ACEi/ARB often first-line), glycaemic control, dietary modification (low salt, phosphate, potassium), erythropoietin for anaemia, vitamin D analogues, statins. Refer to nephrology. Renal replacement therapy (dialysis or transplantation) for End-Stage Renal Disease (ESRD). **Uncomplicated Cystitis:** Short course oral antibiotics (e.g., Trimethoprim or Nitrofurantoin for 3 days; single-dose Fosfomycin). Refer to local guidelines for resistance patterns. **Pyelonephritis:** Oral Ciprofloxacin/Co-amoxiclav for 7-14 days; IV antibiotics (e.g., Ceftriaxone) if severe, septic, or unable to tolerate oral. Obtain urine culture before starting antibiotics. **Renal Colic:** Analgesia (NSAIDs e.g., diclofenac, or opioids). Alpha-blockers (e.g., Tamsulosin) can aid stone passage. Small stones (<5mm) often pass spontaneously. Larger/symptomatic stones: Extracorporeal Shock Wave Lithotripsy (ESWL), Ureteroscopy, or Percutaneous Nephrolithotomy (PCNL). **Nephritic/Nephrotic Syndromes:** Specific management depends on the underlying cause (often immunosuppression with corticosteroids). Manage complications: diuretics for oedema, ACEi/ARB for hypertension/proteinuria, statins for hyperlipidaemia, anticoagulation for nephrotic syndrome if high risk. **BPH:** Lifestyle modifications. Alpha-blockers (e.g., Tamsulosin) for rapid symptom relief. 5-alpha reductase inhibitors (e.g., Finasteride) to reduce prostate size. Transurethral Resection of the Prostate (TURP) if medical therapy fails or complications occur.