Does he have a history of reactions to ingestion of nuts and eggs and milk? What prompted the blood test? The "RAST" IgE testing is the valid blood test but it is subject to false positives. Without a history of (relatively) acute, objective symptoms of IgE-mediated allergies the testing is only a data point.
Confirming this is not one of those other invalid tests such as IgG, ALCAT, E95, etc.
Definitely need more information as most times the blood test is prompted by a huge reaction. What happened, Lindsay? That will help us help you. Either way we'll get you an answer and next steps.