Different Causes Of Altered Mental Status In Children

Coma may be caused by a number of different causes and the etiologies may be divided into structural or medical causes.

Structural Causes
Tend to result in asymmetric or focal neurologic findings, particularly affecting pupillary response, extraocular movements and motor response to pain.

1. Trauma: Typically involves a shearing mechanism (diffuse axonal injury) from rapid deceleration. This shearing forces can rupture blood vessels and result in subdural, epidural or intraparenchymal hemorrhage. When suspected mechanism of injury does not fit extent of patient’s injuries, always consider inflicted trauma or child abuse.

2. Tumor: If a child has a brain tumor symptoms such as headache,vomiting or focal neurologic deficits are typically present for weeks to months. Coma or altered mental status can result from seizures, intracranial hypertension or cerebral edema.

3. Cerebrovascular Event: Hemorrhagic and ischemic strokes occur with the same frequency in children. A ruptured arteriovenous malformation is the most common cause of hemorrhagic stroke in children. Ischemic and thrombotic strokes occur most commonly in children with sickle cell disease and congenital heart defects; less commonly in children with hypercoagulable states, metabolic disorders, vasculitis and other vascular abnormalities. Patients with hemorrhagic stroke tends to present with coma or altered mental status and those with ischemic stroke present with focal neurological deficits.

4. Hydrocephalus: Infants with this condition have an increased head circumference and it is due to increase in the CSF that may be due to a blockage in CSF flow or increased production. Patients may present with coma, altered mental status or irritability and poor feeding.

5. Infection: CNS infection from any source is a cause for confusion, coma or altered mental status.

Medical Causes
It includes all those causes or processes that can decrease the delivery of substrate to the brain. Neurological examination is usually non focal.

1. Infections: Patients present with irritability, lethargy and vomiting. Infection may be a meningitis, encephalitis, subdural empyema or sepsis. All these conditions may cause coma or altered mental status in a child.

2. Poisoning or Overdose: Poisoning or overdose from many substances can cause altered mental status. Because many drugs and toxins are not detectable on serum and urine screening, a high index of suspicion must be maintained and usually a good history helps in the diagnosis.

3. Seizures: Children can present in the postictal state without a witnessed seizure. Seizures may be followed by a transient period of paralysis.

4. Metabolic alterations: Hyper or hypoglycemia, electrolyte imbalances and inborn errors of metabolism all can lead to an altered mental status.

Functional Cause
If all organic causes have been ruled out also function cause should be kept in mind.