Final answer:
The first test for suspected kidney stones is often a diagnostic imaging scan, with computed tomography (CT) being the gold standard. Urine culture and routine urinalysis may precede imaging to exclude infection or assess for other abnormalities. Additional tests or stone analysis may follow depending on initial findings.
Step-by-step explanation:
The first test of choice with suspicion of kidney stones is generally a diagnostic imaging procedure. A non-invasive and highly effective method is the use of a Computed Tomography (CT or CAT scan), considered the gold-standard for detecting kidney stones. However, before imaging, a culture of a urine sample may be performed to exclude urine infection. Depending on the initial results, a doctor might recommend further urine tests, such as a routine urinalysis.
Routine urinalysis assesses kidney function by examining physical attributes of the urine, as well as chemical substances such as protein, glucose, and its pH level. Microscopically, it looks for red and white blood cells, bacteria, and crystals. If necessary, 24-hour urine collection can measure total daily urinary volume and levels of substances like magnesium, sodium, and calcium that may indicate stone-forming tendencies.
Should a stone pass, patients might be advised to catch it at home, typically by urinating through a tea strainer, for later analysis. In some cases, medication such as thiazides or allopurinol may be prescribed, depending on the nature of the stone formation.