Final answer:
The client's creatinine level decreased from 2.5 mg/dL to 1.6 mg/dL by discharge after a drop of 0.9 mg/dL.
Step-by-step explanation:
The client's original creatinine level on admission was 2.5 mg/dL. The question indicates that the creatinine level dropped by 0.9 mg/dL by the time of discharge. To find the client's current creatinine level, we subtract the decrease from the original level:
2.5 mg/dL - 0.9 mg/dL = 1.6 mg/dL
Therefore, the client's creatinine level at the time of discharge is 1.6 mg/dL.