E. Rossoni proposes that this surname would derive from a nickname originating in the Italianization of the Greek term sgurós, which means "curly" or "with hair in ringlets", and which would have been applied to founding ancestors who had a curly head of hair. Rossoni considers it absolutely rare and places it in the Messina area; the variant Isgroi, practically unique, also appears in that same area.

G. Rohlfs agrees on the Greek origin of the surname, though he sets it within the Greco-Byzantine tradition and links it specifically to the Greek-speaking onomastics of Calabria. Rohlfs documents it in the province of Reggio Calabria —in localities such as Mèlito and Villa San Giovanni— and notes that it is also Sicilian. He presents it as a variant of Sgrò, referring the reader to that entry for fuller etymological treatment. Rohlfs further adds that the form Isgro, without the accent, may be the result of the loss of the written accent outside Italy.

Taken together, both authors point to a common Greek base and to a geographical distribution at the southernmost tip of Italy, with a presence in both Sicily and Calabria.