Unmasking the Enigma: Progressive Neurocognitive Decline in a Thriving Adolescent

Abstract

The neurocognitive deterioration accompanied by behavioral disturbance in adolescent or young adult poses a great diagnostic challenge. While there is a tendency to equate behavioral change or disturbance to psychiatric causes, it is essential to consider organic causes, especially when there are other features that would raise clinical suspicions such as progressive neurocognitive decline and the atypicality of the presentation.

This case illustrates a male adolescent with a background of normal development, intellectual and adaptive functioning. He presented with slowly progressive neurocognitive decline since the age of 14 years old. The symptoms became prominent when he started to become forgetful and had deterioration of school performance. His speech and comprehension started to trouble, together with episodes of repetitive motor movements (eye-blinking, hand clenching, lip smacking, and mouth chewing) without impairment in awareness, episodes of bedwetting and daytime somnolence. Later, he portrayed worsening of behavioural disturbances, irritability and impulsivity with prominent ‘pseudo-regression’ in his general maturity and reasoning. Despite on antiepileptic and neuroleptic medication, he showed lack of improvement, raised the suspicion of possible autoimmune in origin. Patient partially responded with intravenous methylprednisolone and behavioural modifications. Unfortunately, the repetitive movement were persistent and EEG was repeated. There was no evidence of epileptiform discharges. The diagnosis of Tourette syndrome has been made eventually.

Correct diagnosis is cardinal for effective treatment. In complex and difficult cases regular monitoring of the symptoms and response to treatment can be an indirect method in establishing one. In cases with such complex, non-specific initial presentation a thorough history taking, examination and investigations are crucial to rule out organic causes. This case is one of the important examples that warrants a great multidisciplinary management and effective communication between all the stakeholders.

Keywords: Neurocognitive decline, adolescent, autoimmune.