Differential Diagnosis
- Single most likely diagnosis: + Urinary Tract Infection (UTI) with ureteral obstruction due to a stone: The presence of many bacteria, WBCs, and RBCs in the urine, along with leukocyte esterase and a positive nitrite test, strongly suggests a UTI. The CT findings of mild left hydroureteronephrosis and a 3 mm stone at or near the ureterovesical junction (UVJ) indicate an obstructing stone causing the infection.
- Other Likely diagnoses: + Pyelonephritis: The combination of UTI symptoms, WBCs in the urine, and the CT finding of hydroureteronephrosis could also suggest pyelonephritis, especially if the infection has ascended to the kidney. + Cystitis: The urinary bladder wall thickening on CT and the presence of WBCs, RBCs, and bacteria in the urine support the diagnosis of cystitis, which could be related to the UTI or the obstructing stone.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.): + Sepsis: Although not directly indicated by the provided information, any infection, especially one involving an obstructed urinary system, carries a risk of progressing to sepsis, a potentially life-threatening condition. + Emphysematous Pyelonephritis: A rare but serious infection of the kidney that can occur in diabetic patients or those with urinary tract obstruction, characterized by gas formation in the kidney.
- Rare diagnoses: + Xanthogranulomatous Pyelonephritis: A rare form of chronic pyelonephritis associated with long-standing urinary tract obstruction and infection, often with stones. + Malakoplakia: A rare inflammatory condition that can affect the urinary tract, often associated with chronic infection and obstruction.