As the plural form "Congressos" implies there were really two congresses, the first in Lisbon (May 5-6), the second in Coimbra (May 8-9), separated by a beautiful all-day scenic drive to the other city.
The President of the Congress in Lisbon was Salazar Leite, the acknowledged leader of Portuguese dermatology. It was solemnly opened in the Aula of the Faculty of Medicine in the very large and modern Hospital de Santa Maria. The first morning session, with Xavier Vilanova in the chair, dealt with "microbiotic eczema of the foot." The subject was presented by Luis Pierini (Argentine) and by Salazar Leite. Individual papers followed. The afternoon session was held in the monumental new Instituto de Medicina Tropical with Luis Pierini presiding. It was devoted to leishmaniasis, with Xavier Vilanova and F. Rabello (Brasil) presenting the subject in masterly fashion and individual papers following. I was especially impressed with
OBERMAYER ME. IV Congressos de Dermatologia Ibero Latino-Americano e Luso-Espanhol. AMA Arch Derm. 1959;80(5):578–579. doi:10.1001/archderm.1959.01560230064012