Gempp E, De Maistre S, Louge P. Serum albumin as a biomarker of capillary leak in scuba divers with neurological decompression sickness. Aviat Space Environ Med 2014; 85:1049–52. Background: Prior reports have shown that decompression sickness (DCS) in scuba divers is accompanied by vascular endothelium damage attributed to gas emboli formation, resulting in capillary leak with hemoconcentration. The significance of serum albumin as a biomarker of vascular permeability in this condition has been insufficiently investigated. We studied whether there was a relationship between low serum albumin values on admission and the occurrence of neurological DCS. Methods: Demographic, diving, and laboratory data of 52 randomly selected DCS divers were compared with those of 52 asymptomatic divers referred for inadequate decompression. The diagnostic performance of serum albumin in predicting neurological DCS was assessed. Results: Both groups did not differ from the variables examined. Serum albumin was significantly lower in injured divers than in controls (38.7 ± 3 g · L⁻¹ vs. 41 ± 2.9 g · L⁻¹). At a cut-off value of 35.2 g · L⁻¹, we found a specificity of 98% (95% CI 90–100) and a sensitivity of 16% (95% CI 7–28) for the prediction of neurological DCS development. Conclusion: Our findings suggest that hypoalbuminemia at initial presentation, albeit rare, accurately predicts the occurrence of neurological DCS in scuba divers. The prognostic value of this biomarker and the potential beneficial role of albumin infusion in more severe cases remain to be investigated.