Chronic Kidney Disease and ESA Guidelines

Lecture 6: Chronic Kidney Disease (CKD)

• CKD is defined as abnormalities of kidney structure or function, persisting for more than 3 months and affecting patient health.
• The abnormalities stem from progressive and irreversible destruction of nephrons.
• Learning objectives include identifying CKD patients, differentiating etiologies, and managing complications.

Definition of CKD

• Abnormalities in kidney structure or function persisting for more than 3 months.
• Influence patient health status
• Complex clinical and biological manifestations due to nephron destruction.
• Temporal criteria: > 3 months
• Functional criteria: eGFR < 60 ml/min/1.73m2
• Structural criteria: Kidney damage

End-Stage Kidney Disease (ESKD)

• Late stage of chronic renal failure
• Without replacement treatment of renal function or renal transplantation, survival is impossible.
• Glomerular filtration rate (GFR) is below 15 ml/min.

Indicators of Kidney Damage

• Albuminuria > 30 mg/day (proteinuria > 150 mg/day)
• Urinary sediment abnormalities (red blood cells, red blood cell casts)
• Electrolyte, acid-base, and metabolic anomalies due to renal tubular dysfunction.
• Histological kidney lesions (kidney biopsy)
• Structural kidney lesions detected by imaging examinations (morphological asymmetry, hyperechogenicity, nephrocalcinosis, contour irregularities, cystic diseases, hydronephrosis)
• History of kidney transplantation

Conditions Associated with Increased CKD Risk

• Diabetes
• Hypertension
• Cardiovascular diseases
• Systemic diseases affecting the kidney (e.g., systemic lupus erythematosus)
• Structural kidney diseases (lithiasis, prostate hypertrophy)
• Weight under 2.5 kg at birth
• First-degree relatives with renal replacement treatment or hereditary kidney diseases
• Chronic exposure to nephrotoxic drugs (NSAIDs)

Prevalence of CKD

• Global prevalence is consistently estimated at 11% to 15%.
• Most cases are at stage 3.
• At least 1 in 10 people suffer from CKD.
• Main causes: diabetes and hypertension.

Incidence of CKD

• Incidence varies by ethnicity.
• CKD is 3-4 times more common in people of Black African descent in the UK and the USA.
• Hypertensive nephropathy is a prevalent cause of ESKD in this group.
• Prevalence is higher in some Asian groups than in white people.

Staging of CKD

• Prognosis of CKD depends on GFR and albuminuria category.
• Details on various stages are provided in the text.

Documentation of Chronic Anomalies

• Dynamic analysis of anomalies (from the patient's history or repeat testing every 3 months) is essential for diagnosis.

Complete CKD Diagnosis

• Includes primary kidney disease and the degree of risk of CKD.
• Indicates eGFR (G) and albuminuria (A) categories.
• Reflects that both parameters correlate with progressive renal impairment and cardiovascular risk.
• Example: CKD chronic glomerulonephritis - with risk that G3aA3.
• Stage 3 CKD is divided in stages 3a and 3b to recognize increased cardiovascular complications with more advanced disease.
• Patients with G2 stage CKD may not show disease unless other damage is present (haematuria, proteinuria, structurally abnormal kidneys, inherited kidney disease or biopsy changes consistent with kidney disease).

Etiology of CKD

• Detailed list of causative factors grouped by disease type.

Screening of CKD

• Methods for detecting CKD (albuminuria, urine dipstick, GFR estimation using serum creatinine).

eGFR Recommendations

• eGFR is a crucial indicator of renal function.
• Value is expressed as a percentage of residual renal function.
• Epidemiological studies link low eGFR (<60ml/min) with increased risk of adverse renal outcomes, requiring renal replacement therapy, and cardiovascular morbidity and mortality.

Progression of CKD

• Rate of renal function decline depends on underlying nephropathy, albuminuria, eGFR at diagnosis, and blood pressure control.
• Chronic glomerular diseases tend to deteriorate faster than chronic tubulo-interstitial nephropathies.

Causes of Accelerated CKD Progression

• Uncontrolled hypertension
• Proteinuria over 0.5g/g
• Cardiovascular disease (heart failure)
• Uncontrolled blood sugar (diabetes)
• Untreated urinary tract obstruction
• Reactivation of primary kidney disease
• Dyslipidemia
• Obesity
• Smoking
• NSAIDs use

Prognosis of CKD

• Correlates with hypertension (especially poorly controlled), proteinuria, and the degree of interstitial scarring on histology.
• Treatment aims to inhibit the effect of angiotensin II and reduce proteinuria using ACEIs and ARBs to help nephroprotection.

Management of CKD

• General measures (diet, body mass control, physical activity, avoiding self-medication, such as NSAIDs).
• Renoprotection (Controlling blood pressure and proteinuria)
• Specific measures for the treatment of causative nephropathy (intensive glycaemic control, immunosuppressive treatment, use of vasopressin V2 receptor antagonists)
• Other measures to limit progression, including controlling dyslipidemia with statins.

Management of CKD-MBD

• Reduction of phosphate and limiting the calcium load (dietary restriction and use of gut phosphate binders)
• Control of PTH with calcitriol vitamin D analogues or calcimimetics.

Cardiovascular Disease in CKD

• Cardiovascular risk is much higher in CKD compared to the general population.
• Risk factors include hypertension, diabetes mellitus, dyslipidemia, smoking, and male gender.
• Conditions like left ventricular hypertrophy and diastolic and systolic dysfunction are common.
• Pericarditis may also occur in CKD stage G5.

Skin Disease in CKD

• Pruritus (itching) is common due to accumulating waste products.
• Nephrogenic systemic fibrosis (NSF) is a fibrosing skin disorder affected by patients with a GFR < 30ml/min and/or undergoing RRT.
• Caciphylaxis (calcific uraemic arteriolopathy) is a rare, life-threatening condition.
• Prevention measures are crucial for managing these complications.

Gastrointestinal Pathologies in CKD

• Uremia halena, nausea, vomiting, intestinal dysmicrobism, gastrointestinal bleeding, and acute pancreatitis are potential complications.

Metabolic Abnormalities in CKD

• Insulin catabolism is altered.
• Renal glucose production is diminished or altered, which impacts insulin requirements in diabetic patients.
• Insulin resistance and impaired glucose tolerance frequently accompany advanced CKD.
• Lipid metabolism is disrupted, leading to impaired clearance of triglyceride particles and hypercholesterolemia, especially in advanced CKD.
• Gout risk increases due to urate retention as GFR declines.
• Multiple other metabolic complications are detailed.

Nervous System Abnormalities in CKD

• Uremia alters the central nervous system.
• Increased circulating catecholamines cause downregulation of a-receptors and impair baroreceptor sensitivity, and affect the autonomic nervous system.
• Median nerve compression in the carpal tunnel and symmetrical polyneuropathy are common consequences.

Correction of Specific Complications

• Includes management of hyperkalemia (using insulin, glucose, sodium bicarbonate, sodium salts of specific anions), acidosis (using bicarbonate), and more.

Precautions in Drug Administration

• Precautions are needed for ACE/ARBs, beta-blockers, statins, NSAIDs, and more because of specific risk factors and renal function.

Renal Replacement Therapy (RRT)

• Initiation is based on the presence of complications associated with decreased GFR (including hyperkalemia, severe metabolic acidosis, severe hyperhydration, uremic pericarditis, signs of uremic intoxication, and persistent GFR below 6-8 ml/min).

Detailed information for each subject can be extrapolated from the OCR text provided.

This quiz explores critical concepts related to erythropoiesis stimulating agents (ESAs) and chronic kidney disease (CKD). Test your knowledge on indications for ESA administration, target hemoglobin ranges, and important monitoring aspects during treatment. Additionally, you'll assess your understanding of kidney function and hemodialysis criteria.