Osmotic Resistance of Erythrocytes and Types of Hemolysis among Foreign Students

This study explores the osmotic resistance of erythrocytes in foreign students from India who came to study at the International Higher School of Medicine in the Issyk-Kul region of Kyrgyzstan. The work was inspired by observations that students arriving from lower-altitude, warmer climates often report fatigue, headaches, and mild weakness during their first weeks at high altitude. These symptoms suggested possible physiological shifts — particularly changes in red blood cell membrane stability under osmotic stress — that warranted scientific examination. The aim of the study was to determine the level of erythrocyte osmotic resistance and to analyze the patterns of hemolysis across different sodium chloride concentrations. The research included 20 clinically healthy male students aged 18–22 years with no history of hematological disorders. Venous blood was collected under standard conditions and added to a series of NaCl solutions ranging from 0.90% to 0.10%. After incubation for 30 minutes and centrifugation, the degree of hemolysis was assessed visually and by spectrophotometry at 540 nm. The results showed that 70% of participants had normal osmotic stability, while about one-third demonstrated a shift of the hemolysis curve toward higher salt concentrations, indicating increased membrane fragility. These findings are interpreted as part of the physiological adaptation process to high-altitude conditions and environmental change. The obtained data have both academic and practical relevance. The osmotic resistance test provides a simple and informative approach to evaluate the adaptive responses of foreign students living and studying in mountainous regions. This method can be used for preventive health assessments, educational laboratory work, and longitudinal monitoring of adaptation during the early stages of residence in Kyrgyzstan.