The diagnosis of high altitude illness by the determination of plasma dermcidin isoform 2 levels by enzyme linked immunosorbent assay.

BACKGROUND

High altitude illness (HAI) is a cluster of syndromes which develops due to the injury of the central nervous system produced by the reduction of the partial pressure of O2 in the atmosphere which disappears on decent. The HAI also results in a prothrombotic condition leading to acute coronary syndrome (ACS), which cannot be controlled on descent to the ground level. There is no diagnosis in HAI to forewarn of the impending ACS. A protein identified to be dermcidin isoform 2 (dermcidin), produced in the system due to environmental stresses, has been reported to be a potent diabetogenic agent. Investigation was carried out to determine the systemic stimulation of dermcidin synthesis at different levels of altitudes in normal adult male volunteers to assess the feasibility of developing a diagnosis for ACS in HAI due to dermcidin synthesis.

METHODS

Normal, nondiabetic, normotensive male volunteers (25 - 35 years old, n = 16) participated in the study. The plasma dermcidin level was determined by enzyme linked immunosorbent assay (ELISA) and by in vitro translation of dermcidin mRNA. The plasma insulin level was determined by ELISA and blood glucose level was determined in a glucometer (Behringer).

RESULTS

The plasma dermcidin level in the volunteers at ground level was 10 +/- 2.10 nM and increased to 80 +/- 4.62 nM at 15000 feet altitude. For each 1000 feet increase of altitude, the dermcidin level increased by 5.83 +/- 0.21 nM with a Coefficient of Correlation "r" = +0.9405. The increase of plasma dermcidin level was found to be inversely related to the decrease of plasma insulin level from 23 microunit/mL to 5 microunit/mL from sea level to 15000 feet height ("r" = -0.9951) with concomitant increase of blood sugar level from 80 +/- 3.6 mg/dL to 135 +/- 2.01 mg/dL.

CONCLUSIONS

These results suggest the feasibility of a diagnosis of a prediabetic condition by determining the plasma dermcidin level in HAI by simple ELISA which may also be useful to forewarn of the possibility of developing an impending prothrombotic condition in HAI.