Diverticulitis-associated urinary findings: The presence of moderate blood and protein in urine, in conjunction with distal colonic diverticulitis shown on CT, suggests that the urinary abnormalities could be secondary to the diverticulitis, possibly due to a colovesical fistula or localized inflammation affecting the urinary tract.

Nephrotic syndrome or nephritic syndrome: The moderate proteinuria could indicate an underlying glomerular disease, although the normal GFR and creatinine levels make this less likely. Further testing, such as urine protein electrophoresis or renal biopsy, might be necessary.
Urinary tract infection (UTI) with negative culture: Although the culture is negative, some UTIs may not be detected by standard cultures, especially if the patient has been on antibiotics recently or if the infection is caused by fastidious organisms.
Hepatorenal syndrome: The elevated liver enzymes (AST, ALT, Alkaline Phos) could suggest liver dysfunction, which, in combination with renal findings, might indicate hepatorenal syndrome, although the GFR is currently normal.

Sepsis: Diverticulitis can lead to perforation and peritonitis, potentially causing sepsis, which is life-threatening and requires immediate intervention.
Obstructive uropathy: Any process that obstructs the flow of urine (e.g., kidney stones, tumors) could lead to renal failure if not promptly addressed.
Vasculitis (e.g., ANCA-associated vasculitis): Although less common, vasculitis can cause both renal and hepatic abnormalities and is critical to diagnose due to its potential for severe morbidity.

Amyloidosis: This condition can cause both proteinuria and elevated liver enzymes, although it is relatively rare and would typically require specific diagnostic testing (e.g., biopsy).
Polycystic kidney disease (PKD): While PKD can cause hematuria and proteinuria, it usually presents with a family history and significant renal cysts visible on imaging, which are not mentioned here.
Membranoproliferative glomerulonephritis: A rare cause of proteinuria and hematuria, often associated with chronic infections, autoimmune diseases, or paraproteinemias, which would require specific diagnostic tests to confirm.