Paul39 is correct. The latest version is known as the "DSM-5". Yes, PTSD is listed as a recognized mental disorder in the DSM5. DSM5 criteria for PTSD are discussed here:

http://www.ptsd.va.gov/professional/PTSD-overview/diagnostic_criteria_dsm-5.asp

My wife works in the mental health field. One word of caution. Once a qualified doctor or mental health professional diagnoses a patient with a specific mental order, that diagnosis will likely follow the patient for the rest of their life. My wife is very cautious regarding assigning certain diagnoses due to the potential long term impact on the patient.