I need help with an ICD-9 code for "increased creatinine". I'm having a moment today! Would you use 790.99 (Findings, abnormal, serum) or 794.4 (findings, abnormal, function study, kidney)? I don't think that 794.4 is appropriate because this code includes scans, uptake studies, etc. and I'm looking for abnormal findings of the blood. 790.99 just doesn't seem specific enough. Is there a better code?