Differential Diagnosis
- Single most likely diagnosis
- Pyelonephritis: The presence of moderate blood, protein, and bacteria in the urine, along with an elevated CRP indicating inflammation, points towards a urinary tract infection involving the kidneys. The absence of hydronephrosis and ureteral stones makes an obstructive cause less likely, but the clinical and laboratory findings are consistent with pyelonephritis.
- Other Likely diagnoses
- Urinary Tract Infection (UTI) with cystitis: Given the findings in the urine analysis (moderate blood, protein, RBCs, and bacteria), a lower urinary tract infection is possible. The presence of bacteria and other abnormalities in the urine suggests an infectious process.
- Diverticulitis: Although the CT scan reports diverticulosis without diverticulitis, the presence of inflammation (elevated CRP) and mild ileus or nonspecific gastroenteritis could be related to diverticulitis, especially if the CT scan missed early or mild inflammation.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Sepsis: The elevated CRP, bands on the CBC, and evidence of infection (bacteria in urine) could indicate a systemic infection. Sepsis is a life-threatening condition that requires prompt recognition and treatment.
- Perforated viscus: Although the CT scan does not show evidence of appendicitis or other obvious sources of perforation, any sign of peritonitis or free air under the diaphragm on imaging would necessitate urgent surgical evaluation. The presence of fluid in the small bowel and colon could be a sign of a perforation, especially if the patient's condition worsens.
- Rare diagnoses
- Vasculitis or autoimmune disorders affecting the kidneys: The presence of blood and protein in the urine could suggest a glomerulonephritis or vasculitis, although these would be less common and typically require additional diagnostic testing (e.g., ANA, anti-GBM antibodies) for confirmation.
- Tuberculosis of the urinary tract: This could present with sterile pyuria (bacteria in the urine without a positive culture) and other systemic symptoms. It's a rare diagnosis in many populations but should be considered in endemic areas or in patients with risk factors.