Analyte	Level	Associated Diseases/Conditions	Diagnostic Context
Urea/BUN	Elevated	Impaired glomerular function, stress, dehydration, hemorrhage into GIT, ↑ protein catabolism (starvation, sepsis), high protein diet	Correlate with creatinine levels; assess patient history for diet, hydration, and potential GIT bleeding.
Creatinine	Elevated	Diet and exercise, muscle disease, obstruction in urinary flow, impaired GFR, artefactual causes (Diabetic ketoacidosis, maple-syrup urine disease)	Differentiate between pre-renal, renal, and post-renal causes.
Cystatin C	Increased	Malignancy, hyperthyroidism, treatment with corticosteroids	Useful in detecting early renal impairment, especially in patients with unusual muscle bulk.
Urine Protein	Elevated	↑ filtration, ↓ reabsorption, cardiovascular disease morbidity and mortality	Confirm with further testing due to potential interferences.
Urine Glucose	Present	DM (hyperglycemia) or low renal threshold (pregnancy)	Correlate with blood glucose levels to differentiate between DM and low renal threshold.
Urine Ketones	Present	Lipid metabolism vs. starvation	Assess patient history to differentiate between lipid metabolism issues and starvation.
Urine Blood	Present	Trauma (vascular injury), renal calculi, pyelonephritis, cystitis (+WBC), drugs, heavy exercise, menstruation	Verify with microscopy to confirm the number and assess patient history.
Urine Bilirubin	Present	Liver - jaundice, hepatocellular disease, obstruction	Evaluate liver function tests to confirm liver involvement.
Urine Nitrites	Present	Gram (-ve) bacteria	Perform microscopy and culture to confirm bacteriuria and identify the specific bacteria.
Urine Leucocytes	Present	Acute inflammation, UTI, acute glomerulonephritis	Look for segmented neutrophils on microscopy to confirm acute inflammation or infection.
Specific Gravity	Elevated	Dehydration, DM, CHF, proteinuria, adrenal insufficiency	Assess patient's hydration status and other clinical signs.
Urine pH	Acidic (<7)	Unable to excrete H^+, high protein diet, starvation, etc.	Evaluate dietary habits and acid-base balance.
Urine pH	Alkaline (>7)	Vomiting, renal tubular acidosis, metabolic/respiratory alkalosis	Assess for acid-base disorders and vomiting history.
Plasma Potassium	Elevated	↓ heart rate	Assess heart rate
Plasma Potassium	Decreased	↑ myocardial excitability (arrhythmia)	Assess myocardial excitability (arrhythmia)
Chloride	Elevated	Renal tubule defect, gastrointestinal losses, aldosterone deficiency	Evaluate renal function and aldosterone levels.
Chloride	Decreased	Prolonged vomiting, diabetic ketoacidosis, aldosterone excess, pyelonephritis (loss of salts)	Assess vomiting history, diabetic status, aldosterone levels, and signs of pyelonephritis.

Renal Function Notes