[The 479th case: cognitive impairment, respiratory failure, colon mass].

A 78-year-old man was admitted to Peking Union Medical College Hospital with fever, weakness of lower extremities, less speech, loss of memory. Fever was relieved after antibiotic treatment, while cognitive impairment and disorder of consciousness progressed rapidly, followed by critical pulmonary infections, respiratory failure, and septic shock. Lab tests showed negative occult blood, normal serum CEA level and positive Anti-nuclear-antibody. PET-CT suggested that strong FDG uptake signals were seen at sigmoid, while bilateral frontal lobe, temporal lobe, parietal lobe, posterior cingulate gyrus showed lower metabolic activity. Colonoscopy biopsy revealed differentiated adenocarcinoma of sigmoid colon. Therefore, paraneoplastic syndrome of nervous system secondary to colon cancer was considered. Rapid and proper diagnosis and treatment were completed by multidisciplinary team including departments of neurology, gastroenterology, general surgery, ICU, rheumatology, clinical nutrition. The laparoscopic sigmoid colectomy was performed under general anesthesia. The patient finally presented with significant improvement of cognition and consciousness. Respiratory function was totally recovered.