Sertaridou EN, et al. - In this study, researchers examined critically ill patients who were admitted in the intensive care unit (ICU) with septic shock or developed septic shock during their ICU stay for the potential alterations of circadian rhythmicity of urine 6-Sulfatoxymelatonin (aMT6s) and cortisol excretion, in a prospective fashion and on successive occasions (septic shock and recovery). Observations revealed induction of inverse changes of aMT6s and cortisol circadian rhythm profiles both within and between different groups of patients by septic shock, depending on timing of onset. They noted a correlation of reduced rhythmicity with severity of disease and longer ICU stay.