During the mid-sixteenth century, begging was banned in Rome and the shelter was converted into fabbriche della salute ("health factory").

The institute was recognized in 1572 by Pope Pius V and was nicknamed "Fatebenefratelli", a phrase used by the saints while inviting passersby to do charity.

These three "mysterious" people were three friars who acted as buyers in disguise to elude the law still in force against possessing the work of religious hospitals.

During the nineteenth century, the hospital was strengthened against the floods of the Tiber River with the erection of surrounding walls.

With the Nazi occupation of Italy in September 1943 and the imposition of antisemitic laws against the Roman Jews, Sacerdoti – with the approval of Borromeo and Bialek – brought patients from the Jewish hospital to be cared for at Fatebenefratelli.

[3] "Syndrome K" was purported to be a neurological illness whose symptoms included convulsions, dementia, paralysis, and, ultimately, death from asphyxiation.

Maurizio and Borromeo, other doctors on staff assisted the Jewish patients and helped to move them to safer hideouts outside the hospital.

Maurizio and Borromeo also installed an illegal radio transmitter in the hospital basement and made contact with General Roberto Lordi of the Italian Royal Air Force.

After World War II, Borromeo was lauded by Government of Italy for his work and was recognized as a Righteous Among the Nations by Yad Vashem.