Differential diagnosis in mild brain injury: understanding the role of non-organic conditions

Over one million mild traumatic brain injuries (TBI) occur annually in the United States. Most of these patients recover full function within about 3 months, but a significant minority do not. Failure to recover as expected following a diagnosed or suspected mild TBI is most commonly related to a concurrent diagnosis or alternative diagnosis or condition. Consideration during the diagnostic process must be given to alternative organic conditions (prior or unsuspected severe TBI, pain, medication side effects or dementia), pre-existing non-organic conditions (active or dormant psychiatric conditions, pre-existing personality characteristics, or social/economic factors), non-clinical conditions (compensation/litigation, malingering) or post-injury psychiatric morbidity (notably depression, anxiety, post-traumatic stress disorder, panic disorder, or conversion disorder). Scrupulous care must be given during the history, physical examination, and neuropsychologic assessment of the patient to evaluate for different or contributory diagnostic possibilities; not all patients that have symptoms following a blow to the head have traumatic brain injury as the sole etiologic agent for their symptoms. Accurate diagnosis will lead to better treatment and optimal outcomes. Future research should focus on early identification of the 'slow to recover' group to allow early and appropriate treatment.