A Rare Case of Pyelonephritis With Methicillin-Resistant Staphylococcus aureus (MRSA) Bacteremia Complicated by Renal Vein Thrombosis.

Pyelonephritis is a significant urinary tract infection (UTI) that can lead to serious complications, including bacteremia and renal vein thrombosis (RVT). This report presents a case of pyelonephritis caused by methicillin-resistant (MRSA), which progressed to RVT. We report a case of a 44-year-old male patient who presented with dysuria, increased urinary frequency, and urine retention over the past three days. His condition deteriorated, leading to reduced urine output and acute urinary retention. Notably, the patient did not report pyuria, hematuria, or fever, and there was no history of nephrolithiasis or recent urogenital procedures. Blood and urine cultures confirmed the presence of MRSA. A contrast-enhanced CT scan of the abdomen revealed left pyelonephritis complicated by abscess formation in both the left kidney and the prostate, as well as left RVT. This case highlights the potential complications of pyelonephritis, such as RVT, and underscores the importance of early diagnosis and intervention. Clinicians should maintain a high vigilance for RVT in patients with pyelonephritis and bacteremia, as timely management can significantly improve patient outcomes.