HYPOXANTHINE LEVELS IN VITREOUS-HUMOR - A STUDY OF INFLUENCING FACTORS IN SUDDEN-INFANT-DEATH-SYNDROME

Elevated hypoxanthine (Hx) levels in the vitreous humor of victims of the sudden infant death syndrome (SIDS) have been been claimed to indi cate hypoxia before death. An important methodologic problem is the te mperature-dependent Hx increase after death. Although most previous st udies have corrected for expected postmortem Hx increase, the aim of t he present study was to omit this problem by matching the subjects of the different groups studied for similar postmortem time. Thirteen cas es of violent death, 11 cases of borderline SIDS, 22 cases of death fr om infectious disease, and 17 cases of death from heart/lung disease w ere compared with a 3-fold number of SIDS cases. To investigate the im pact of environmental factors on the Hx levels of the SIDS cases, the following possible confounding factors were investigated: attempt to r esuscitate, slight infections before death, sleeping position, and tim e of the day when found dead. To investigate whether the size of the e yeball would influence the Hx level, five cases of violent death in ch ildren were compared with 15 adults who died suddenly. The vitreous hu mor Hx level was significantly higher in SIDS victims than in cases of violent death (p < 0.01) and deaths due to heart/lung disease (p < 0. 01), whereas no such difference was found either between SIDS and bord erline SIDS or SIDS and infectious death. There were no differences be tween any of the subgroups of SIDS victims. The vitreous humor Hx leve l in small children and adults did not differ. The findings raise the question of possible similarities in death mechanism in SIDS and infec tious death.