haematuria

A 48-year-old woman presents with acute onset severe left flank pain radiating to the groin, associated with nausea. She denies fever or dysuria. Vitals are stable. Urinalysis shows haematuria. Serum creatinine is 75 µmol/L. An ultrasound is performed. Considering the clinical presentation and the findings demonstrated in the provided image, which of the following is the most appropriate next diagnostic step?

A 38-year-old man presents with sudden onset severe left flank pain radiating to the groin, associated with nausea. He is afebrile, blood pressure 140/90 mmHg, heart rate 95 bpm. Urinalysis shows microscopic haematuria. Serum creatinine is 80 µmol/L. An ultrasound is performed. Considering the clinical presentation and the findings demonstrated in the provided image, which of the following best explains the mechanism of the patient's pain?

A 45-year-old male presents to the emergency department with sudden onset severe left flank pain radiating to the groin. He reports some nausea but no vomiting. His temperature is 37.5°C, pulse 88 bpm, BP 130/80 mmHg, respiratory rate 16/min, oxygen saturation 98% on room air. On examination, he has significant left costovertebral angle tenderness. Urinalysis shows microscopic haematuria and trace leukocytes. His creatinine is 90 µmol/L (baseline unknown). An ultrasound of the kidneys is performed, shown in the image. Based on the clinical presentation and the finding shown in the image, what is the most appropriate immediate next step in management?

A 38-year-old woman presents with sudden onset, severe left flank pain radiating to her groin. She reports associated nausea but denies fever or dysuria. On examination, she is afebrile, blood pressure 125/75 mmHg, heart rate 80 bpm. Urinalysis shows microscopic haematuria. Serum creatinine is 80 µmol/L. An ultrasound is performed. Considering the clinical presentation and the findings demonstrated in the provided image, which of the following is the most likely underlying mechanism causing the patient's pain?