A 60 year old man is brought to a psychiatrist with a 10 year history, that he suspects his neighbors and he feels that whenever he passes by they sneeze and plan against him behind his back. He feels that his wife has been replaced by a double and calls police for help. He is quite well- groomed, ale, occasionally consumes alcohol, likely diagnosis is:-

Kindly note that this patient also has Capgras syndrome (feeling that his wife has been replaced by a double) which is usually seen in patients with schizophrenia. Also the history is suggestive of delusion of persecution. Also, note that he is quite well groomed suggesting that personality is preserved as is seen in patients with paranoid schizophrenia. Paranoid schizophrenia * Predominant positive symptoms Most common Late onset Good prognosis * Personality preserved (daily activities & social interaction are normal)