A 49-year-old male presented to the ER with a chief complaint of increased urinary frequency for 4 days. He was seen in the ER 3 days ago, diagnosed with urinary tract infection (UTI), and sulfamethoxazole/trimethoprim was prescribed. Urinary frequency decreased but his urine turned dark and he developed fever and chills.
What can be the cause of this change? Should any radiological test be recommended?