What is the diagnosis for a patient with leukocytosis (elevated White Blood Cell count), normal Comprehensive Metabolic Panel (CMP), urinary tract infection (UTI) symptoms, including pyuria (White Blood Cells in urine), hematuria (Red Blood Cells in urine), bacteriuria (bacteria in urine), and radiographic evidence of left hydroureteronephrosis, a 3mm ureterovesical junction (UVJ) stone, and cystitis?

Differential Diagnosis

• Single most likely diagnosis
  • Urinary Tract Infection (UTI) with obstructing kidney stone:
    • The presence of many bacteria, WBCs, and RBCs in the urine, along with a 3 mm stone at or near the ureterovesical junction (UVJ), supports this diagnosis. The patient's mild left hydroureteronephrosis and urinary bladder wall thickening also suggest an obstructive process with associated cystitis.
• Other Likely diagnoses
  • Pyelonephritis:
    • The patient's elevated WBC count, particularly the segmented neutrophil absolute count, and the presence of WBCs and RBCs in the urine could indicate an upper urinary tract infection.
  • Cystitis:
    • The urinary bladder wall thickening and the presence of leukocyte esterase, WBCs, and RBCs in the urine support this diagnosis.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Sepsis:
    • Although the patient's CMP is unremarkable, the elevated WBC count and the presence of a possible infection source (obstructing kidney stone with UTI) necessitate consideration of sepsis, especially if the patient shows signs of systemic illness.
  • Urosepsis:
    • Similar to sepsis, the combination of an obstructing stone with infection could lead to urosepsis, a life-threatening condition.
• Rare diagnoses
  • Xanthogranulomatous pyonephrosis:
    • Although rare, this condition could be considered in the presence of a long-standing obstructing stone and chronic infection, especially if there's significant renal parenchymal damage.
  • Emphysematous pyelonephritis or cystitis:
    • These are rare but serious infections that could be life-threatening, particularly in diabetic patients or those with immunocompromising conditions. The presence of hepatic steatosis and the current diagnosis does not directly suggest these conditions, but they should be considered in the appropriate context.