Clinical Manifestations of Uremia

Uremia, resulting from acute or chronic renal failure, is characterized by the accumulation of metabolic waste products, electrolyte imbalances, endocrine dysfunction, and systemic toxicity. As the condition progresses, symptoms intensify across multiple organ systems.

(1) Neurological Symptoms

Early signs include dizziness, headaches, fatigue, and cognitive decline (impaired memory/concentration). Advanced stages may present with agitation, muscle twitching, seizures, or coma, attributed to:

• Neurotoxin accumulation
• Electrolyte/acid-base disturbances
• Cerebral hypoxia and edema (from renal hypertension)

(2) Gastrointestinal Symptoms

• Initial signs: Loss of appetite, indigestion
• Progression: Nausea, vomiting, diarrhea, or GI bleeding (due to ammonia-induced mucosal inflammation from bacterial urea breakdown).

(3) Cardiovascular Symptoms

• Heart failure/arrhythmias from hypertension, anemia, and hyperkalemia.
• Uremic pericarditis (fibrinous exudate; chest pain and friction rub on auscultation).

(4) Respiratory Symptoms

• Kussmaul breathing (deep, slow respirations in acidosis).
• Uremic fetor (ammonia-like breath from urea decomposition).
• Pulmonary edema (heart failure/hypoalbuminemia) or calcific pneumonitis (calcium-phosphate deposits).

(5) Dermatological Symptoms

• Pruritus (toxin-induced or secondary hyperparathyroidism).
• Yellow-gray skin (melanin deposition), xerosis, and uremic frost (urea crystals on sweat glands).

(6) Metabolic Disorders

A. Impaired Glucose Tolerance

• Insulin resistance due to:
  • ↓ Insulin secretion
  • Growth hormone antagonism
  • Toxin interference (urea/creatinine).

B. Negative Nitrogen Balance

• Causes cachexia, hypoalbuminemia, and edema. Contributing factors:
  • Reduced protein intake (anorexia/vomiting).
  • ↑ Catabolism (methylguanidine/infection).
  • Protein loss (bleeding/urinary leakage).

C. Hypertriglyceridemia

• Driven by ↑ hepatic VLDL synthesis and ↓ lipoprotein lipase activity (linked to methylguanidine).