A 32-year-old male presents to the emergency department with sudden onset severe, colicky pain in the right lower back that radiates to the groin. The pain started approximately six hours ago and has progressively worsened. The patient describes the pain as sharp and intermittent, with associated nausea but no vomiting. He reports difficulty finding a comfortable position and has been unable to urinate since the pain began. He denies any fever, chills, or blood in his urine, but mentions he has had occasional discomfort with urination in the past few weeks.

The patient has no significant past medical history, although he admits to inadequate fluid intake and a diet high in sodium and oxalate-rich foods (e.g., spinach, nuts). He is otherwise healthy and has no known history of kidney disease or urinary tract infections.

On examination, the patient is in visible distress and has tenderness over the right costovertebral angle. There is no fever or signs of systemic infection. Urinalysis reveals microscopic hematuria. A non-contrast abdominal CT scan is performed, which shows a 6mm stone located in the right renal pelvis.

The patient is diagnosed with a renal stone and is started on pain management, IV fluids, and instructed on lifestyle modifications, including increasing fluid intake. If the stone does not pass spontaneously within a few days, further interventions such as lithotripsy may be considered.