An apparent life-threatening event (ALTE) is the sudden occurrence of certain alarming symptoms such as prolonged periods of no breathing (apnea), change in color or muscle tone, coughing, and gagging in children under 1 year of age.
ALTE is not a specific disorder. It is a group of symptoms that occur suddenly in young children.
The most common causes of ALTE include gastroesophageal reflux disease, nervous system disorders (such as seizures, meningitis, or brain tumors), and infections. Less common causes include heart disorders, metabolic disorders, child abuse, and narrowing or complete blockage of the airways. A cause cannot be determined in about 50% of cases.
An ALTE usually is characterized by an unexpected, sudden change in an infant's breathing that alarms the parent or caretaker. Features of an event include some or all of the following:
When an ALTE occurs, the doctor asks several key questions:
The doctor does a physical examination to check for obvious defects, particularly nervous system abnormalities, such as being too stiff (posturing) or being too floppy (poor muscle tone), and signs of trauma.
The doctor may do laboratory tests (such as liver function, blood, stool, and urine tests), imaging tests (such as a chest x-ray or computed tomography [CT] of the head), electrocardiography, or a combination based on the examination findings. Tests (such as electroencephalography—see Symptoms and Diagnosis of Brain, Spinal Cord, and Nerve Disorders: Electroencephalography) to check for other possible causes also may be done.
The cause, if identified, is treated. Infants who have required CPR or have had any abnormalities identified during the examination or initial laboratory testing are hospitalized for monitoring and further evaluation.
Parents and caregivers should be trained in CPR for infants and in general safe infant care (such as putting infants to sleep on their back and eliminating exposure to tobacco smoke). Doctors sometimes recommend home apnea monitoring devices for a limited period of time. Monitors that can record the infants' breathing pattern and heart rate are preferred to those that simply sound an alarm. Recording monitors may help doctors distinguish false alarms from real events.
Last full review/revision February 2009 by Elizabeth J. Palumbo, MD