Need Advise. Something more dangerous?

Pls if someone could help share their views! On 28th Mar'22, my sister who is 37 years has blood pee in the morning with no pain whatsoever. She visited the doctor same day in the evening by that time, amount of blood had reduced in pee on its own but was still visible. The GP said CT test would be required and proposed next week date. However, in the meanwhile the doctor prescribed CIPROFLOXACIN 500 mg to be consumed every 12 hours for next 7 days. The blood in urine has further reduced after consuming 2 tablets so far. Reading above, pls suggest based on your vast experience if its the case of some  infection or stone or something more dangerous? There is no other symptom and my sister had her period 2 weeks back. Any suggestions are most welcome