We report a case of a 50-year-old shepherd hospitalized in intensive care unit for hiatal hernia complicated by an occlusive syndrome. In post-surgery, an acute respiratory distress occurs due to mediastinitis with large pleural effusion. At the laboratory, direct examination of the pleural sample revealed the presence of pseudohyphae. Kazachstania slooffiae was identified by Mass Spectrometry and confirmed by DNA sequencing. This uncommon yeast has never been previously described in human infections. Although its pathogenicity is not well known, K. slooffiae should be considered in the case of critically ill patients.