Chronic Kidney Disease

Chronic Kidney Disease (CKD), also known as chronic renal disease, is a long-term condition characterised by a progressive loss of kidney function over months or years. Initially, CKD may be asymptomatic, but as the disease progresses, symptoms such as leg swelling, fatigue, vomiting, loss of appetite, and confusion may develop. Complications include heart disease, high blood pressure, and anaemia. The primary causes include diabetes, high blood pressure, glomerulonephritis, and polycystic kidney disease. Risk factors include genetic predisposition and low socioeconomic status.

Signs and Symptoms

In the early stages, CKD often presents no symptoms and is typically detected through routine blood tests showing increased serum creatinine or protein in the urine. As the disease progresses, the following symptoms may appear:

• Increased blood pressure due to fluid overload and hormonal changes.
• Accumulation of urea leading to azotaemia and uraemia.
• Hyperkalaemia, causing symptoms ranging from malaise to potentially fatal cardiac arrhythmias.
• Fluid overload leading to oedema or pulmonary oedema.
• Hyperphosphataemia and hypocalcaemia, contributing to cardiovascular risks and bone disease.
• Anaemia due to reduced erythropoietin production.
• Cognitive decline and sexual dysfunction.

Causes

The leading causes of CKD include diabetes mellitus, hypertension, and glomerulonephritis. Other causes can be classified by anatomical location:

• Vascular disease: Includes large-vessel diseases like bilateral kidney artery stenosis and small-vessel diseases like ischaemic nephropathy.
• Glomerular disease: Such as focal segmental glomerulosclerosis and IgA nephropathy.
• Tubulointerstitial disease: Includes drug- and toxin-induced nephritis.
• Obstructive nephropathy: Caused by conditions such as bilateral kidney stones.

Genetic conditions like polycystic kidney disease and environmental factors such as exposure to high temperatures in fields are also causes.

Diagnosis

Diagnosis involves a combination of history, physical examination, and laboratory tests, including serum creatinine levels and urine dipstick tests. Differentiating CKD from acute kidney injury (AKI) is very important. Screening is recommended for at-risk individuals, such as those with hypertension, diabetes, or a family history of kidney disease.

Ultrasound

Kidney ultrasonography helps in diagnosis, showing increased echogenicity and decreased kidney size due to disease progression.

Treatment

Treatment aims to manage symptoms and slow disease progression through lifestyle changes and medication.

Blood Pressure Management

ACE inhibitors (ACEIs) and angiotensin II receptor antagonists (ARBs) are first-line treatments to slow kidney function decline and reduce cardiovascular risks.

Other Measures

• Lipid Management: Aggressive treatment of high blood lipids.
• Dietary Management: Low-protein, low-salt diet to slow CKD progression.
• Anaemia Management: Target haemoglobin level of 100–120 g/L, with parenteral iron and erythropoietin replacement.
• Bone Disease Management: Calcitriol for vitamin D deficiency and phosphate binders for elevated serum phosphate levels.
• Sexual Dysfunction: Phosphodiesterase-5 inhibitors and zinc for men.

Lifestyle Interventions

Obesity and high dietary sodium intake are risk factors. Weight management and salt restriction can help manage CKD, though evidence for other interventions like omega-3 supplementation and protein supplements is mixed.

Renal Replacement Therapy

In advanced CKD (stage 5), dialysis or kidney transplant is required. Dialysis helps manage uraemic toxins, though it is not as effective as a fully functioning kidney.

Prognosis

CKD significantly increases the risk of cardiovascular disease, which is the leading cause of death in CKD patients. While kidney replacement therapies can prolong life, they often come with reduced quality of life. Kidney transplantation improves survival rates but comes with short-term surgical risks. High-intensity home haemodialysis shows better outcomes compared to conventional methods.

Epidemiology

Globally, CKD affected 753 million people in 2016, with 1.2 million deaths in 2015. The prevalence is higher in populations with risk factors like diabetes and hypertension and varies across different regions and ethnic groups.

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Self-assessment MCQs (single best answer)

What is a primary cause of Chronic Kidney Disease (CKD)?

Which of the following is NOT a symptom of advanced CKD?

What is a common complication of CKD?

What laboratory test is typically used to detect CKD in its early stages?

Which medication is commonly used to manage high blood pressure in CKD patients?

In advanced CKD, what treatment option becomes necessary?

What dietary recommendation is often given to CKD patients to slow disease progression?

Which imaging technique is used to diagnose CKD by showing changes in kidney size and echogenicity?

Which electrolyte imbalance is commonly seen in CKD patients?

Which factor is NOT a risk for developing CKD?