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**Overview**: Calcium Creatinine Ratio Panel**Introduction**: The Calcium Creatinine Ratio Panel is a diagnostic tool designed to assess calcium excretion using urine samples. In India, hypercalciuria is a major risk factor for kidney stones (prevalence 5-15 percent in adults, higher in northern states due to dietary patterns, low fluid intake, and vitamin D excess/deficiency imbalance), contributing to recurrent nephrolithiasis. Calcium/creatinine ratio (normal <0.21 mg/mg) helps evaluate urinary calcium loss and stone risk without 24-hour collection. High morbidity from underdiagnosis in rural/low-SES populations, limited urology access, repeated stone episodes leading to renal impairment or obstruction. Per clinical pathology and biochemistry practices aligned with ICMR and Indian Society of Nephrology guidelines, the test employs spectrophotometry for calcium, creatinine, and ratio calculation over 1-2 days with high accuracy, valuable for spot urine screening in stone formers or hypercalcemia suspects. This diagnostic falls under kidney stone screening and targets patients with recurrent stones or calcium metabolism issues, addressing accurate detection to guide hydration, diet (low oxalate/salt), or thiazides. With elevated morbidity due to underdiagnosis, the test supports public health efforts by enabling precise risk assessment, facilitating prevention, and reducing stone recurrence. Its urine-based approach ensures reliable detection in India's diverse laboratory settings.**Other Names**: Ca Cr Ratio Pnl.**FDA Status**: FDA approved, CLIA certified for biochemistry/clinical pathology, compliant with 2025 standards.**Historical Milestone**: Spot urine ratio adopted for convenience; in India, widely used in nephrolithiasis clinics.**Purpose**: The test assesses 3 parameters including urine calcium and creatinine to calculate ratio, guide calcium excretion evaluation, detect hypercalciuria, inform stone prevention.**Test Parameters**: 1. Urine Calcium, 2. Urine Creatinine, 3. Calcium/Creatinine Ratio.**Pretest Condition**: Fasting 10-12 hours recommended; patients should report recurrent kidney stones, flank pain, or family history.**Specimen**: 10 mL urine in 1 sterile container, transported within specified times to maintain sample viability.**Sample Stability at Room Temperature**: 24 hours with proper handling to preserve analyte integrity, ensuring reliable test performance.**Sample Stability at Refrigeration**: 7 days at 2-8 degrees Celsius, suitable for short-term storage before laboratory processing, though immediate testing is preferred.**Sample Stability at Frozen**: 6 months at -20 degrees Celsius, allowing long-term storage for retesting, though freezing may affect some analytes.**Medical History**: Patients should provide details on stone episodes, diet (high salt/dairy), fluid intake, family stone history, medications.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of untreated hypercalciuria including recurrent stones or renal damage, benefits of early detection, and minimal discomfort from urine collection.**Procedural Considerations**: The test involves sample processing using spectrophotometry by trained personnel to ensure sterile technique, avoid contamination, and interpret results within 1-2 days using provided controls. Laboratories must maintain a controlled environment, adhere to quality assurance protocols, and store kits according to manufacturer specifications to ensure reliability.**Factors Affecting Result Accuracy**: Delays beyond stability periods, improper storage conditions, dehydration, or dietary variations can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Elevated ratio indicates hypercalciuria, necessitating specialist input. Normal may require follow-up in stone formers.**Specialist Consultation**: Nephrologists or urologists should be consulted for management.**Additional Supporting Tests**: 24-hour urine calcium, stone analysis for confirmation.**Test Limitations**: Spot ratio may vary with hydration; comprehensive approach required.**References**: Indian Journal of Nephrology 2024, Nephrolithiasis Studies India 2023. |
