Continuing Education Activity

Psychiatric symptoms are a common comorbid feature of hypothalamic hamartoma with epilepsy. They are most disabling and are a significant challenge for the patient and their families. Most commonly, psychiatric symptoms present with externalizing behaviors such as aggression and rage attacks. This activity reviews the evaluation, treatment, and management of psychiatric symptoms and discusses the role of the interprofessional team in the care of patients with this condition.

Objectives:

• Determine the etiology of hypothalamic hamartoma with epilepsy.

• Apply the typical presentation of psychiatric symptoms in patients with hypothalamic hamartoma and epilepsy.

• Identify the treatment and management of psychiatric symptoms in patients with hypothalamic hamartoma and epilepsy.

• Communicate the importance of improving care coordination, collaboration, and communication amongst an interprofessional team members to enhance care for patients with psychiatric symptoms associated with hypothalamic hamartoma and epilepsy.

Introduction

Hypothalamic hamartomas are benign congenital tumors that arise from the ventral hypothalamus.[1][2] Research has identified 2 clinical phenotypes of hypothalamic hamartoma: parahypothalamic and intrahypothalamic hamartoma.[3] Parahypothalmic hamartomas, or pedunculated, are attached to the anterior hypothalamus. Parahypothalamic hamartomas are highly associated with central precocious puberty, whereas intrahypothalamic hamartoma attached to the posterior hypothalamus correlates highly with treatment-resistant epilepsy.[4][5] This treatment-resistant epilepsy mainly starts with gelastic (laughing) seizures, which later develop into other resistant seizure types, including localization-related and generalized seizures. Nearly 40% of patients with hypothalamic hamartoma have both central precocious puberty and epilepsy; however, this is more related to larger lesions that arise from the anterior and posterior hypothalamus.[4]

The intrahypothalamic subtype of hypothalamic hamartoma, in particular, is also associated with neurobehavioral comorbidity, including cognitive impairment and psychiatric symptoms.[6][7] Cognitive impairment varies in patients, from mild to severe, depending on the earlier age of onset of the first seizure, frequency, size, and the number of antiepileptic drugs.[8][9]

Psychiatric symptoms are a common comorbid feature of hypothalamic hamartoma with epilepsy.[10] These are most disabling in patients and are a significant challenge for the patient and their families. Most commonly, psychiatric symptoms present with externalizing behaviors such as aggression and rage attacks. Patients can also have a reduced threshold for frustration, with extensive reactivity to minor stimuli, which can also result in destructive physical features.[3]

Etiology

A hamartoma is a discrete lesion that resembles a neoplasm but often arises from an errant organ and contains atypical portions of tissue elements.[11] Hypothalamic hamartomas are rare congenital benign tumors that contain atypical portions of neuronal tissue elements.[12]

Hypothalamic hamartoma develops in the fifth to sixth week of gestation and appears in or around the hypothalamus, arising from infundibular recess and mammillary bodies. There is a theory that a defect in the fetal development of the hypothalamus results in the development of a tumor. Pathologically, hypothalamic hamartoma consists of mature neurons and glial cells ranging from 10 to 30 mm.[13]

The cause of hypothalamic hamartoma remains unknown. Cases are usually sporadic, with no identified family history, and the patient remains the only affected individual.[14] However, hypothalamic hamartomas are also associated with rare genetic disorders such as Pallister-Hall syndrome. Pallister-Hall syndrome is an autosomal dominant disorder caused by a mutation to the GLI3 gene, which classically presents with hypothalamic hamartoma and polydactyly.[15]

Epidemiology

The estimated prevalence of hypothalamic hamartoma with epilepsy is 1 case per 50000 to 100000 in children and adolescents.[11] The prevalence of hypothalamic hamartoma with only precocious puberty remains unclear. For hypothalamic hamartomas with epilepsy, males are at a slightly higher risk than females, with a ratio of 1.3 to 1.[16] Hypothalamic hamartomas occur worldwide with no specific geographic concentration of cases. The current thinking is that all ethnic groups are at equal risk, with no identified maternal risk factor or fetal exposures.

History and Physical

The clinical presentation of hypothalamic hamartomas depends on their attachment region to the hypothalamus.[12] Clinically, hypothalamic hamartomas present as 2 recognized subtypes: parahypothalamic and intrahypothalamic hamartomas.

Parahypothalmic hamartomas, also known as pedunculated, occur in the anterior hypothalamus, arising from the inferior surface of the hypothalamus, tuber cinereum. This subtype of hypothalamic hamartoma is associated with central precocious puberty.[4] Central precocious puberty associated with hypothalamic hamartomas starts early at an average age of 3.7 years in boys and 2.5 years in girls.[17]

Conversely, intrahypothalamic hamartomas, also know as ‘sessile’ occur in the posterior hypothalamus with an attachment level at the mamillary bodies.[2] Intrahypothalamic hamartomas are associated with gelastic seizures, epilepsy, cognitive impairment, and psychiatric symptoms.[3][18] Gelastic seizures are rare forms of seizure characterized by inappropriate smiling, giggling, or laughter associated with video electroencephalogram (EEG) changes and unrelated to external or interpersonal stimulation.[19] These seizures classically occur in infancy with increasing frequency and periodicity.[20] The mean age of presentation of gelastic seizures is 2.8 years, with the age of onset ranging from 1 month to 15 years. Gelastic seizures can be a precursor to other seizure types, cognitive deterioration, and behavioral abnormalities. The clinical spectrum of hypothalamic hamartoma-associated epilepsy ranges from sporadic and easily controlled partial seizures to seizures partially responsive to epileptic drugs and a catastrophic course that requires surgical intervention.[21][22]

Cognitive impairment can present as language delay with learning disabilities. Behavioral disorders are associated more commonly with hypothalamic hamartomas and gelastic seizures. These include attention deficit hyperactivity disorder (ADHD) (75%), aggressiveness, anxiety, oppositional defiant disorders (83.3%), and conduct disorders (33.3%).[11] Other behavioral disorders include rage, temper tantrums, and violence. Anxiety and mood disorders ( 8.3% to 25%) can also present as phobias, post-traumatic stress disorder, avoidant disorder, major depression, and dysthymia. 

Patients with gelastic seizures present with affective aggression. The definition of affective aggression is being out of control, damaging one's property, physical harm to oneself, being aggressive without a purpose, being aggressive with stronger children when aggressive, and expressing remorse after aggression. Some children also present with predatory aggression. Predatory aggression includes the ability to control one's behavior when aggressive, protect oneself when aggressive, fight with weaker children, and try to get something out of being aggressive. More commonly, patients with hypothalamic hamartomas and gelastic seizures support affective aggression. These aggressive episodes arise suddenly and are not motivated by ill will towards the victims.[11]

Other predictive factors associated with an increased likelihood of aggression include male gender, the presence of intellectual disability, younger age at the time of first seizure, and multiple seizures. Postulates are that seizure activity in patients with hypothalamic hamartoma is a contributing factor to neurobehavioural deficits. The causes of rage and aggression are poorly understood but are thought to be influenced by gender and hormonal dynamics.[23]

Evaluation

Since hypothalamic hamartomas present with a plethora of psychiatric symptoms, these patients need a thorough neuropsychiatric evaluation process. Diagnostic tools can be useful, including the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) and the Overt Aggression Scale.[24] Other aggression scales, such as the Vitiello Aggression Scale, differentiate affective and predatory aggression.[25] Head magnetic resonance imaging (MRI) confirms the presence of hypothalamic hamartoma. MRI is the primary diagnostic tool for hypothalamic hamartomas, as surgical specimens are difficult to obtain.[26] Central precocious puberty may be caused by excessive secretion of gonadotropin-releasing hormone (GnRH) from the lesion.[27] 

Child and adolescent psychiatrists frequently have to evaluate youth presenting with rage and anger. Distinguishing between predatory and affective aggression at this time is very important. Also, if the patient presents with a history of inappropriate smiling or giggling, this should alert the psychiatrists that gelastic epilepsy could be present, and the patient should obtain a referral for a thorough neurological assessment. Gelastic seizures often fail to demonstrate EEG changes; therefore, a video EEG is recommended.[28] Video EEG captures the gelastic seizure with head deviation and twitching.[29] Further, if the patient presents with findings of aggression and precocious puberty, a complete, thorough assessment by an endocrinologist is also required.

Treatment / Management

The gelastic seizures associated with hypothalamic hamartomas are complicated to treat or manage.[30] These seizures are refractory to medical treatment, and reports exist of surgical attempts to control the seizures. However, in some instances, the surrounding hypothalamic tissue interferes with safe surgical access, so alternative modalities include stereotactically targeted radiation therapy or radiofrequency lesioning.[31] Recent studies have reported a complete resection is not necessary and disconnecting the tumor is sufficient for seizure control, therefore less invasive modalities are increasingly being used. The main disadvantages of the non-surgical approach are a delayed effect on seizure control, which usually takes about 6 months, radiation damage to the surrounding vital structures such as the optic tract, and lower efficacy of seizure control in contrast to the open surgical approach.[13]

If precocious puberty is the isolated finding with the hamartoma, then medical management is focused on suppressing the pubertal development. An example of this treatment plan would be the administration of gonadotropin-releasing hormone analog.[32] Long-acting LH-RH analogs suppress gonadotrophin secretion. Therefore, treatment with LH-RH analogs is the first choice.[26] However, if this does not help, then surgical removal is recommended. In contrast to intrahypothalamic hamartomas, parahypothalamic hamartomas are relatively easily accessible for surgical removal.[32]

There are no proposed treatment algorithms for behavioral and psychiatric symptoms in patients with hypothalamic hamartoma.[12] There is also, as yet, no documented, specific pharmacotherapy for psychiatric symptoms in patients with hypothalamic hamartomas.[3] Behavioral difficulties are addressable through parent management training (PMT). This training involves teaching parents strategies to increase prosocial skills and decrease disruptive behaviors in children. An example of PMT is a brief behavioral intervention program. This program demonstrates successful results in treating symptoms of ADHD and disruptive behaviors in children with parahypothalamic hamartomas.[33]

Behavioral symptoms are common in children with epilepsy. Often, parents report their children being more restless and irritable before seizure onset. Controlling seizures ultimately controls aggressive behavior in children. The literature describes this phenomenon in several places. Surgical removal of hypothalamic hamartoma is the more definitive treatment in controlling seizures. After surgical removal, 3 patients became seizure-free, 8 had over 90% reduction in seizures, and all of these eleven patients experienced a dramatic improvement in behavior and cognition.[21]

Differential Diagnosis

Hypothalamic hamartomas are unique in their presentation with gelastic seizures. Other tumors arising from the ventral hypothalamus, such as craniopharyngiomas, astrocytomas, and optic nerve gliomas, do not usually present with gelastic seizures. However, these tumors can be associated with endocrine dysfunction and are very rarely associated with central precocious puberty. The differential diagnosis for incessant laughter is broad; however, a thorough history and physical exam, along with neuroimaging, video EEG, and psychiatric screening, can aid in the diagnosis of gelastic seizures with hypothalamic hamartomas.[29]

Prognosis

Prognosis is dependent on numerous factors such as the size, location, early manifestations of gelastic seizures, behavioral and cognitive impairment, and central precocious puberty. Large sessile hypothalamic hamartomas are likely to have all of the above features.

The success rate for gonadotropin-releasing hormone agonist therapy is high in treating central precocious puberty.[34] Monitoring pubertal progression is all that is required, however regular testing for luteinizing hormone (LH) and sex steroids can further confirm treatment efficacy.[17] When puberty is desirable, the clinician can discontinue hormone therapy.[34] Long-term outcomes of girls and boys treated with GnRH therapy appear favorable.[35][36]

Gelastic seizures are quite distressing for the patient and the family. As they tend to be refractory to antiepileptic drugs, surgery is the predominant treatment choice. Neurosurgical techniques tend to resolve the symptoms rapidly in these patients. Early intervention is quite critical as this condition is progressive, with worsening cognitive and behavioral issues over time. The lesion is often inaccessible through an open approach; therefore, minimally invasive surgical or radiological therapies are options, but with variable outcomes. Only 50% of the patients achieved a cure by endoscopic disconnection of hypothalamic hamartomas.[37] This partial improvement with the persistence of seizures in patients suggests that over time, a secondary independent epileptogenic area develops in the cortex.[38] A short window of under 10 years has been proposed from epilepsy onset to surgical treatment in hypothalamic hamartoma to prevent the development of independent stage and cure epilepsy.[39]

Complications

Complications with open surgical procedures are high.[13] Various minimally invasive and non-surgical methods have been used to treat hypothalamic hamartoma. The main disadvantage of non-surgical methods such as gamma knife radiation is the delayed effect on seizure control, which can take 6 months or longer. A recent trial reported that 37% of patients were seizure-free after gamma knife radiation therapy, and 60% had a dramatic improvement in symptoms.[31] Radiation damage can also occur to the surrounding vital structures, such as the optic tract. Possible complications associated with surgical resection include pituitary endocrinopathies and hypothalamic obesity syndrome.[17] As hypothalamic hamartoma is a rare disease disorder, complications, and adverse effects remain unknown.

Deterrence and Patient Education

Patients and families require education regarding gelastic seizures, as these can be quite challenging to manage. Parents should understand the potential for rage behaviors, mood disorders, and aggression in patients with hypothalamic hamartoma and epilepsy — approximately 43% of patients present with significant aggression.[3] Parents should also receive counsel on the progressive nature of the disease with worsening seizures, cognitive decline, and behavioral deterioration.[12] Regular follow-up by an interprofessional team of professionals is necessary to manage this disease successfully.

Enhancing Healthcare Team Outcomes

The management of hypothalamic hamartomas is best done chiefly with an interprofessional team because of its rarity and vague symptoms. Clinicians need to be aware that besides seizures, these lesions can present with psychiatric symptoms in the form of rage behaviors, mood disorders, and aggression.[7] There is a general lack of clinical data on such significant comorbidity. Risk factors for psychiatric comorbidity in patients with hypothalamic hamartoma are unknown. Predictors for the increased possibility of aggression are male gender, intellectual disability, early age at the onset of seizure activity, and multiple seizures instead of only gelastic seizures. Atypical presentations of mood or psychiatric symptoms should call for imaging studies of the brain.

Early seizure onset is also associated with cognitive impairment. The neurobiology of rage and aggression is poorly understood but is mostly under the influence of hormonal dynamics such as cortisol and testosterone.[40] Patients with hypothalamic hamartoma present with a broad spectrum of psychiatric symptoms. It is challenging to categorize based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), as symptoms from all categories can be involved virtually. Therefore, hypothalamic hamartoma is classified as purely symptomatic.

Psychiatric outcomes improve after surgery in patients with hypothalamic hamartoma with epilepsy. There is no current available pharmacotherapy for psychiatric symptoms recommended at this time, and further clinical trials are needed to explore this possibility.

Despite the absence of a pharmaceutical standard of treatment, when pharmaceutical therapy is the initial treatment option, the pharmacist must be involved, verify dosing, and assist the team by performing medication reconciliation. Clinicians can monitor the effectiveness of treatment and are also in the best position to observe for adverse medication effects and assist in helping if a surgical option is chosen. All providers are responsible for educating and counseling the patient's family regarding gelastic seizures. Only with a full, interprofessional team approach can outcomes be directed optimally.