Humans are social animals and have progressed to the state we're in largely down to our ability to learn from each other's experiences, rather than having to experience each lesson ourselves. This demands that we be capable of putting ourselves in the place of another. This ability is called empathy. Empathy is at the core of what makes us human.
Failure to empathise is the result of a mental abnormality. This may be permanent or temporary, and to a lesser or greater degree. At the shorter and lower end of the scale it may be attributable to tiredness, stress/adreneline, or drugs, for instance. At the other end of the scale mental illness/congenital abnormality is the only rational explanation.
Not the medical professions' official view, but it is mine.
And that places paedophilia very squarely under 'mental health', imo.