Chronic renal failure, also known as chronic kidney disease (CKD), is a progressive condition characterized by the gradual loss of kidney function over months to years. Recognizing, diagnosing, and managing CKD effectively is crucial to delay progression, manage complications, and improve patient outcomes. This guide will focus on the key aspects of history-taking, examination findings, investigations, and management plans tailored to junior doctors.
History Taking
When approaching a patient with suspected chronic renal failure, focus on eliciting details that help identify the cause, assess severity, and recognize complications. Key questions include:
· Symptoms of kidney dysfunction:
Fatigue, weakness: Could indicate anemia or electrolyte imbalances.
Oedema: Ask about swelling in the legs, ankles, or face, as fluid retention is common.
Dyspnea or orthopnea: May suggest pulmonary oedema due to fluid overload.
Nausea, vomiting, anorexia: Non-specific but can indicate uremia.
Nocturia, oliguria, or polyuria: Changes in urine output can provide clues to the degree of kidney function.
Pruritus: Uremic toxins can cause itching.
Bone pain: Can be due to renal osteodystrophy.
Risk factors:
Hypertension and diabetes mellitus: The two most common causes of CKD.
History of glomerulonephritis or urinary tract infections.
Family history of renal disease: Consider genetic causes like polycystic kidney disease.
Medication history: Especially nephrotoxic drugs like NSAIDs, ACE inhibitors, ARBs, and certain antibiotics.
History of cardiovascular disease: CKD and cardiovascular disease often coexist.
Past medical history:
Autoimmune conditions: Lupus, vasculitis, or other systemic diseases can affect the kidneys.
Obstructive symptoms: Ask about changes in urinary flow, hesitancy, or pain, which may suggest post-renal causes like benign prostatic hyperplasia or kidney stones.
Examination Findings
Physical examination can provide important clues to the severity of CKD and its complications. Look for:
Vital signs:
Blood pressure: Hypertension is both a cause and consequence of CKD. Check for postural hypotension, which may indicate volume depletion or autonomic dysfunction.
General appearance:
Pallor: Anemia from decreased erythropoietin production.
Edema: Periorbital or peripheral oedema suggests fluid retention.
Cachexia or muscle wasting: Seen in advanced CKD due to malnutrition or protein loss.
Uremic frost: A rare finding in severe uremia where crystallized urea deposits on the skin.
Cardiovascular:
Raised jugular venous pressure (JVP): Indicates fluid overload.
Auscultate for a pericardial rub: Uremic pericarditis may develop in end-stage renal disease (ESRD).
Auscultation of the heart: A left ventricular heave may indicate left ventricular hypertrophy (common in CKD).
Abdominal:
Palpable kidneys: May indicate polycystic kidney disease.
Auscultate for renal bruits: Suggests renal artery stenosis.
Neurological:
Peripheral neuropathy: Uremia can cause sensorimotor neuropathy.
Cognitive dysfunction or confusion: Uremic encephalopathy may occur in advanced cases.
Musculoskeletal:
Bone tenderness or deformities: CKD-related bone disease (osteodystrophy) may cause bone pain and deformities.
Investigations
The aim of investigations is to confirm the diagnosis, assess the severity of CKD, identify the underlying cause, and evaluate for complications.
Blood tests:
Serum creatinine and eGFR: Key markers for assessing renal function. CKD is classified into stages based on eGFR.
Electrolytes (sodium, potassium, bicarbonate): Hyperkalemia and metabolic acidosis are common complications.
Full blood count (FBC): Look for anemia (normocytic, normochromic).
Calcium, phosphate, and parathyroid hormone (PTH): Indicative of bone disease and secondary hyperparathyroidism.
Urea: Elevated levels in uremia.
Liver function tests (LFTs): To exclude hepatorenal syndrome.
Urinalysis:
Proteinuria or hematuria: These can suggest glomerular disease.
Urine albumin-to-creatinine ratio (ACR): Helps quantify proteinuria, which is a marker of CKD progression.
Urinary sediment analysis: Look for red cell casts (glomerulonephritis) or white cell casts (infection).
Imaging:
Renal ultrasound: To assess kidney size, cortical thickness, and rule out obstructive causes like stones or hydronephrosis. Small, shrunken kidneys suggest chronic disease.
Doppler studies: To evaluate renal artery stenosis if suspected.
CT or MRI: May be required for detailed assessment of structural abnormalities.
Special tests:
Renal biopsy: Indicated when there is uncertainty about the cause of CKD, especially in cases of rapidly progressive glomerulonephritis or nephrotic syndrome.
Management Plan
Management of CKD focuses on slowing disease progression, managing complications, and preparing for renal replacement therapy in advanced stages.
· Lifestyle Modifications:
Dietary advice:
Low sodium diet: Helps manage hypertension and fluid overload.
Protein restriction: To reduce the workload on kidneys (discuss with a dietitian).
Phosphate control: Avoid high-phosphate foods, and consider phosphate binders in advanced stages.
Smoking cessation and weight loss: To reduce cardiovascular risk.
· Pharmacological Treatment:
Blood pressure control: Aim for <140/90 mmHg (or <130/80 mmHg if proteinuria). ACE inhibitors or ARBs are preferred to reduce proteinuria.
Glycemic control: Tight control of blood sugar in diabetic patients (target HbA1c <7%).
Management of complications:
Hyperkalemia: Treat with calcium gluconate, insulin with dextrose, and consider sodium bicarbonate or dialysis if refractory.
Acidosis: Sodium bicarbonate supplementation may be necessary.
Anemia: Administer erythropoiesis-stimulating agents (ESAs) and iron supplementation.
Bone disease: Treat with vitamin D analogs and manage hyperphosphatemia with phosphate binders.
· Renal Replacement Therapy (RRT):
Indications for dialysis or transplant: Consider RRT in stage 5 CKD (eGFR <15 mL/min), uremic symptoms, refractory hyperkalemia, or acidosis.
Types of dialysis: Hemodialysis or peritoneal dialysis may be initiated depending on patient factors.
· Referral to Nephrology:
Referral is indicated for patients with an eGFR <30 mL/min, rapid progression of CKD, or difficulty managing complications (e.g., refractory hypertension, hyperkalemia, or bone disease).
Chronic renal failure is a complex condition requiring a multidisciplinary approach. Early identification and intervention can slow disease progression and prevent complications. As a junior doctor, developing a systematic approach to history-taking, examination, and investigations will help you provide optimal care for CKD patients.
Comentários