Rosh Emergency Medicine Practice Test

Which diagnostic test is most appropriate for a patient with mild flank pain and urinary urgency but unremarkable urinalysis?

1. A. Cystoscopy

2. B. Kidney ultrasound

3. C. Noncontrast CT of the abdomen and pelvis

4. D. Prostate biopsy

The correct answer is: B. Kidney ultrasound

A kidney ultrasound is the most appropriate diagnostic test in this scenario due to the presentation of mild flank pain and urinary urgency, coupled with an unremarkable urinalysis. This combination of symptoms suggests the possibility of a urinary tract obstruction or the presence of kidney stones, which might not be visible on a urinalysis. A kidney ultrasound is a non-invasive imaging modality that can effectively assess the anatomy of the kidneys and urinary tract. It can help identify structural abnormalities, blockages, or any dilatation of the renal pelvis or ureters that could account for the patient's symptoms. It is particularly valuable as an initial study since it carries no radiation risk and provides important information about the renal parenchyma and surrounding structures. The other options involve more invasive procedures or less appropriate imaging methods given the current symptoms and findings. Cystoscopy, while useful for evaluating lower urinary tract problems, might not be necessary at this stage given the unremarkable urine findings. Non-contrast CT scans are excellent for diagnosing urinary stones but involve radiation exposure and may be reserved for cases where a more urgent and serious condition is suspected. A prostate biopsy would be inappropriate as it does not directly relate to the patient's stated symptoms and is indicated only in the context of suspected prostate