A vitreous sample from a decomposed body shows glucose of 0 mg/dL, hypoxanthine of 350 µmol/L, and urea of 12 mmol/L. The MOST likely interpretation of the markedly elevated hypoxanthine is:
- A The deceased had chronic gout before death
- B Elevated hypoxanthine indicates ante-mortem hypoglycaemia
- C Hypoxanthine accumulates from adenosine triphosphate (ATP) degradation and is a useful postmortem interval marker, especially in early decomposition when potassium is unreliable ✓
- D Hypoxanthine indicates vitreous contamination with vitreous bacterial flora
Correct answer: C. Hypoxanthine accumulates from adenosine triphosphate (ATP) degradation and is a useful postmortem interval marker, especially in early decomposition when potassium is unreliable
Explanation
Hypoxanthine is an adenine nucleotide catabolism product: ATP → ADP → AMP → IMP → hypoxanthine. It accumulates progressively in vitreous after death and correlates with PMI in early postmortem periods. Elevated hypoxanthine (>200 µmol/L) is useful as a PMI marker when vitreous potassium accuracy is compromised. It is unrelated to ante-mortem gout (which affects serum urate, not vitreous hypoxanthine) and is not a contamination marker.
Reference: The Essentials of Forensic Medicine and Toxicology (Narayan Reddy), 34th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.