The nurse should expect the following findings in a toddler with hemolytic uremic syndrome:
1. Creatinine: The nurse should expect the creatinine level to be elevated, indicating kidney damage. Therefore, option A is incorrect.
2. Hemoglobin (Hgb): In hemolytic uremic syndrome, red blood cells are destroyed, leading to a decrease in hemoglobin levels. Therefore, option B is incorrect.
3. Urine casts: In hemolytic uremic syndrome, the urine may show the presence of casts, which are cylindrical structures formed in the renal tubules. Additionally, blood and protein may be present in the urine. Therefore, option C is incorrect.
4. BUN (Blood Urea Nitrogen): The BUN level is a measure of kidney function. In hemolytic uremic syndrome, the BUN level is likely to be elevated due to kidney damage. Therefore, option D is the main answer.
In conclusion, the nurse should expect an elevated BUN level in a toddler with hemolytic uremic syndrome. The other findings mentioned in the options are not consistent with this condition.