You are looking for the .Font.Italic
property. Test the following. Modify accordingly.
Sub AddItalicizedNums()
Dim TargetRng As Range, Cell As Range
Dim SumOfItalics
Set TargetRng = Range("OneToTwenty")
SumOfItalics = 0
For Each Cell In TargetRng
If Cell.Font.Italic = True Then
SumOfItalics = SumOfItalics + Cell.Value
End If
Next Cell
MsgBox SumOfItalics
End Sub
Screenshot:
My named range is OneToTwenty
and I italicized (and boldfaced) all even numbers in it. The sum is showing correctly, as shown in the message box.
Let us know if this helps.