Infants with an apparent life-threatening event (ALTE) should not be treated nor monitored without a detailed medical evaluation, as different medical causes may be responsible for the initial clinical presentation. Standard and specific evaluation procedures are listed to help identify a cause for the ALTE. The most frequent problems associated with an ALTE are digestive (about 50%), neurological (30%), respiratory (20%), cardiovascular (5%), metabolic and endocrine (under 5%), or diverse other problems, including child abuse. Up to 50% of ALTEs remain unexplained. The finding of medical or surgical anomalies leads to specific treatments. Surveillance programmes with the use of home monitoring devices may be undertaken, preferably with cardiorespiratory monitors, and when possible, with event monitors, although no currently available home monitoring device is free of false alarms or offers complete protection. Long-term follow-up programmes of infants with an apparent life-threatening event contribute to adapt medical attitudes to the child's needs and to confirm the medical diagnosis.
Conclusion: a systematic diagnostic evaluation, together with a comprehensive treatment programme, increases survival and quality of life for most affected infants.