SIR: The syndrome of increased intracranial pressure without hydrocephalus, or mass lesion with normal cerebral spinal fluid (CSF) composition, previously known as pseudotumor cerebri, is now termed idiopathic intracranial hypertension (IIH).1 Typically, it occurs in obese but otherwise healthy women of childbearing age. A case of IIH in an adolescent presenting with psychiatric symptoms is described.
A 14-year-old adolescent girl was referred for inpatient psychiatric treatment by the partial program she was attending for self-injurious behavior. Prior to this, at age 12, the patient started complaining of daily headaches associated with dizziness and nausea. After a comprehensive neurological workup, she was diagnosed with IIH as she was found to have bilateral papilledema, increased CSF pressure on lumbar puncture and a normal MRI. Secondary causes of increased intracranial pressure, including drugs and vitamin A, were excluded. The patient was subsequently treated with acetalzolamide but due to no response, it was discontinued. The patient was then tried on topiramate but her neurological symptoms continued. A couple of months after the onset of neurological symptoms, she also developed affective symptoms, characterized by mood swings ranging from being depressed and lethargic to being happy and energetic. She also developed transient binge eating and trichotillomania. In addition, she developed psychotic symptoms, including referential delusions, delusions of thought broadcast and auditory hallucinations, the voices telling to hurt herself. Besides this, she also displayed selective mutism and dissociative symptoms wherein she would go into a "trance-like" state. During this state, she would stare into empty space, be nonresponsive to verbal commands and would utter sentences or scribble on a paper. Such episodes occurred three or four times a week, each lasting several minutes. She had no recollection of these episodes. During one such episode, she wandered out in the rain and had to be brought back. Two subsequent EEGs were read as normal. The patient continued to display the above symptoms despite sequential and/or combined trials with acetazolamide, topiramate, fluoxetine, quetiapine and cyproheptadine over the past 2 years. Finally, while an inpatient, she was treated with only gabapentin (200 mg/day) after the neurologist suggested benefit with this drug in headaches in children. At the time of discharge, patient no longer displayed self-injurious behavior and had no dissociative spells but continued to experience psychotic symptoms. She is currently being followed-up by the neurology and the partial program that referred her. This patient had family history of depression but no history of psychotic disorder. There was nothing to suggest trauma or abuse.
The notable feature of this patient’s presentation was the multitude of psychiatric symptoms, spanning the affective, psychotic and dissociative spectra. Whether IIH caused this presentation or unmasked an underlying diathesis is not clear. One study on women with IIH showed higher rates of depression and anxiety.2 Only one report describes psychosis in a patient developing pseudotumor cerebri due to hypervitaminosis A.3 In this case, the patient initially had depression alternating with bouts of elation, and later developed paranoid ideation. The patient recovered following withdrawal of Vitamin A. Other reports cited by the above article mention lethargy, loss of interest, irritability and insomnia as some of the psychiatric symptoms of increased intracranial tension.3
There are, however, no reports of dissociative symptoms associated with IIH. This condition, by definition, is without any structural brain changes on neuroimaging. But studies have shown diffuse cerebral blood flow abnormalities in IIH,4 and such global cerebral abnormalities can partly explain the myriad symptoms in this patient. Interestingly, cerebral blood flow abnormalities have also been documented with ketamine, a dissociative anesthetic, and also in patients with posttraumatic stress disorder experiencing dissociative flashbacks.5,6 The underlying neurochemical basis of IIH is poorly understood but one report cites glutamine, converted from glutamate in astrocytes, in part, mediating the increased intracranial hypertension by osmotic action.7 With increased glutamate transmission hypothesized to cause dissociative symptoms in PTSD,8 further research in this direction is encouraged.