What initial investigations should be conducted in a patient suspected of having AML, and how should I interpret the results?

For a patient suspected of having leukaemia, including acute myeloid leukaemia, the initial investigation to consider is a very urgent full blood count (within 48 hours) ³.

This investigation should be offered to adults presenting with any of the following symptoms: pallor, persistent fatigue, unexplained fever, unexplained persistent or recurrent infection, generalised lymphadenopathy, unexplained bruising, unexplained bleeding, unexplained petechiae, or hepatosplenomegaly ³.

For children and young people, a very urgent full blood count (within 48 hours) should be offered if they present with pallor, persistent fatigue, unexplained fever, unexplained persistent infection, generalised lymphadenopathy, persistent or unexplained bone pain, unexplained bruising, or unexplained bleeding ³. Children and young people with unexplained petechiae or hepatosplenomegaly should be referred for immediate specialist assessment ³.

The provided guidelines indicate that the purpose of the full blood count is to "assess for leukaemia" ³. However, the supplied context does not detail specific interpretation criteria for the full blood count results to diagnose acute myeloid leukaemia, nor does it outline further initial investigations beyond the full blood count for this specific condition.