Physical examination in a patient who has just recovered from a paroxysmal event may hint at the diagnosis. In case of Patient X, physical examination revealed mild right hemiparesis with a reduction of tone and reflexes consistent with a post–ictal state. This is classical of seizures. The past history of Patient X is commendable. Birth history revealed that patient X was born 5 weeks before due date. However neonatal period was uneventful. The boy suffered from vague headaches at the age of 4 for about 4 months. Though physical examination was normal, he did have some attention deficit and increased activity.
Retrospectively, one can attribute these symptoms to nocturnal seizures. Seizures during sleep can lead to worsening of attention, cognitive functioning and quality of life. The boy also suffers from multiple allergies. Infact, there is a positive family history of allergies and sinus problems. Whether there is a link between allergies and seizures is not yet known. Certain allergies like allergy to non- steroidal anti- inflammatory drugs may contribute to seizures6 Nocturnal seizures are to be investigated like any other seizures3. The first and foremost investigation would be Electroencephalography (EEG).
Not all cases of seizures have abnormal EEG, but if a patient has abnormal EEG, then the diagnosis is evident. EEG can detect interictal epileptiform discharges or focal abnormalities, thus helping to arrive at a diagnosis. However, the criterion standard for diagnosis and classification of epileptic seizures includes the interpretation of sleep-deprived EEG2. Video-EEG monitoring is useful to establish a definitive diagnosis of spells with impairment of consciousness3. It is performed to rule out an epileptic etiology with a high degree of confidence if the patient has demonstrable impairment of consciousness during the spell in question.
It is also useful to characterize the type of seizure and epileptic syndrome to optimize pharmacologic treatment2. In Patient X, EEG revealed moderate generalized abnormalities consistent with a seizure diathesis. The clinical presentation and nature of EEG hints at partial seizures in Patient X. Seizures can be classified as partial seizures, generalized seizures and unclassified seizures4. Partial seizures can be simple or complex. In simple seizures, the consciousness is retained and they can be motor, sensory, autonomic or psychic. In complex seizures, the consciousness is impaired.
Generalized seizures can be absence type, generalized tonic- clonic, tonic, clonic, myoclonic, atonic and infantile spasms. Other investigations which may be useful are neuroimaging studies. Brain MRI or head CT scan can help in detecting structural abnormalities that can cause seizures. Brain MRI is a better imaging study to look into subtle abnormalities2. In Patient X, MRI impressions indicated small bilateral focal areas of high signal in the occipital white matter which suggested post-infectious, inflammatory or ischemic changes. This is commendable considering his past history.
These changes are probable due to premature delivery and subsequent periventricular leukomalacia. Blood investigations are usually useful if some metabolic cause or electrolyte disturbance is suspected as a cause of seizures. CSF analysis is useful if meningitis or encephalitis is suspected. Elevated prolactin levels can give a clue as to the etiology of seizures. A 3- or 4- fold rise in the levels is more likely to occur in generalized tonic-clonic seizures than with other seizure types2. The mainstay of treatment is anticonvulsant medication. Anticonvulsants can be divided into 8 large groups based on their mechanisms, as follows2: