Analyze the case below, answer the questions with rationales to support your answers.  A 27 yr. old man presents in the eme

Analyze the case below, answer the questions with rationales to support your answers. 

A 27 yr. old man presents in the emergency room (ED) in handcuffs, escorted by two police officers for an evaluation for causing a ruckus outside a grocery store and threatening store customers. The patient refuses to participate much during an interview.  He yells let me go or they are going to get me! They have been after me for years! You cant let them get me! He denies depressed mood or SI/HI or A/V H, and prior psychiatric and medical problems. He denies taking prescription medication or illegal drugs. In response to marijuana use, he retorts, “it’s legal now.” He prematurely ends the interview stating , refusing to answer any further questions because they can hear us.  The patient refused to provide any contacts from which to gather collateral information.

On mental status examination the patient appears disheveled and dirty, he acts suspicious and guarded, avoiding eye contact.  His speech is difficult to follow, and he often turns his head away  and mumbles to himself. His affect is blunted.  He looks around abruptly several times and appears to be responding to internal stimuli.

1. Describe the conditions that will need to be ruled out before a psychiatric diagnosis can be made.
2. Discuss any diagnostic work up you think is necessary, provide your rational. 
3. Does the patient require psychiatric hospitalization? What’s your rationale for your decision?
4. Discuss your most likely diagnosis with the evidence to support your decision?
5. Provide your references.