Evidence‑Based Management of Nephrolithiasis

Acute Renal Colic Analgesia

NSAIDs (e.g., diclofenac, ibuprofen, metamizole) are recommended as first‑line analgesics for renal colic because they lower the need for additional pain medication compared with opioids. Strength: strong recommendation. 1
Opioids (e.g., hydromorphine, pentazocine, tramadol) should be reserved for second‑line use; they are associated with higher rates of vomiting and greater requirement for rescue analgesia. Strength: strong recommendation. 1

Patients presenting with sepsis and/or anuria due to an obstructed kidney require immediate decompression by percutaneous nephrostomy or ureteral stenting. Strength: strong recommendation. 1
Urine should be cultured before and after decompression, and empiric broad‑spectrum antibiotics started promptly, with later adjustment according to susceptibility results. Strength: strong recommendation. 1
Definitive stone removal should be postponed until the septic episode has resolved. Strength: strong recommendation. 1

Alpha‑blockers are strongly recommended for patients with distal ureteral stones larger than 5 mm who are suitable for conservative (non‑surgical) management; the greatest benefit is seen with stones >5 mm. Strength: strong recommendation (off‑label class effect). 1

All stone formers should aim for a daily urine output of at least 2 L (≈2 L of fluid intake) to achieve roughly a 50 % reduction in stone recurrence. Strength: moderate‑quality evidence. [2][3]
Patients already achieving adequate fluid volumes or those with contraindications such as decompensated heart failure should not be urged to increase intake further. Strength: moderate‑quality evidence. [2][3]

Calcium: Maintain dietary calcium intake of 1,000–1,200 mg/day from foods; low‑calcium diets increase stone risk by enhancing intestinal oxalate absorption. Strength: guideline consensus. 4
Sodium: Limit sodium to ≤2,300 mg/day (≈6 g salt) because higher sodium raises urinary calcium excretion. Strength: guideline consensus. 4
Animal Protein: Reduce animal protein consumption, as its metabolism generates sulfuric acid that increases urinary calcium and uric acid while lowering protective citrate. Strength: guideline consensus. 4
Oxalate: Restrict high‑oxalate foods (e.g., spinach, nuts, chocolate) only when urinary oxalate exceeds 40–45 mg/day; otherwise restriction yields minimal benefit. Strength: guideline consensus. 4
Potassium‑Rich Foods: Increase intake of fruits and vegetables to provide potassium, citrate, magnesium, and phytate, all of which protect against stone formation. Strength: guideline consensus. 4
Vitamin C: Avoid vitamin C supplements because they increase endogenous oxalate production and may raise stone risk. Strength: guideline consensus. 4

Initiate monotherapy with a thiazide diuretic, potassium citrate, or allopurinol; each agent effectively reduces calcium stone recurrence. Strength: moderate‑quality evidence. [2][3]
Combination therapy does not provide additional benefit over monotherapy. Strength: moderate‑quality evidence. [2][3]
Escalate to medication after 6–12 months of optimal dietary measures if stones recur. Strength: guideline consensus. 4

Thiazide Diuretics: Effective for hypercalciuria; efficacy is enhanced by concurrent sodium restriction. Strength: guideline consensus. 4
Potassium Citrate: Increases urinary citrate, a key inhibitor of calcium‑oxalate crystallization. Strength: guideline consensus. 4

Oral alkalinization with potassium citrate or sodium bicarbonate to achieve urine pH 7.0–7.2 is strongly recommended; this regimen can dissolve uric acid stones. Strength: strong recommendation. 1
Reported success rate is approximately 80 % (with ~16 % of patients needing subsequent intervention). Strength: strong recommendation. 1
Patients should regularly monitor urine pH and adjust alkalinizing therapy accordingly. Strength: strong recommendation. 1

Obtain urine microscopy and culture before any stone‑removal procedure to identify and treat urinary infection beforehand. Strength: strong recommendation. 1
Provide a single‑dose peri‑operative antibiotic to all patients undergoing endourological stone treatment (e.g., ureteroscopy). Strength: strong recommendation. 1
For high‑risk patients undergoing percutaneous nephrolithotomy, an extended pre‑operative antibiotic course markedly reduces postoperative sepsis and fever. Strength: strong recommendation. 1
Choose the prophylactic agent based on local antimicrobial susceptibility patterns. Strength: strong recommendation. 1

Perform stone composition analysis for every first‑time stone former to guide individualized prevention strategies. Strength: strong recommendation. 1
More detailed analytical programs are reserved for patients identified as having a high risk of recurrence. Strength: strong recommendation. 1

Do not prescribe low‑calcium diets; they paradoxically increase stone risk by promoting oxalate absorption. Strength: guideline consensus. 4
Do not focus solely on oxalate restriction without ensuring adequate calcium intake at meals to bind dietary oxalate in the gut. Strength: guideline consensus. 4
Avoid pethidine as an opioid analgesic because it is associated with a high incidence of vomiting. Strength: strong recommendation. 1