LEUCOCYTES CONTAINING BACTERIA IN PLAIN BLOOD FILMS FROM PATIENTS WITH SEPTICÆMIA

A search for infected cells was made with the low power (× 10 or × 20) objective in plain blood films from patients known to have, or suspected of having, septicæmia. It was found that scanning of a film in this way for a short time will detect even small concentrations of infected cells. Infected leucocytes occurred in highest concentration in the first drop of blood issuing from the previously unmanipulated ear lobe. They occurred most frequently in films in which there was also an increase in mononuclear cells containing inclusions of corpuscular origin, and were found whether or not the patient had recently been given apparently effective antibiotic treatment. Consideration is given to the requirements for a diagnosis of septicæmia from the presence of infected cells in blood films and the distinction of bacteria from other structures in leucocytes which may resemble them. A search for infected leucocytes in a plain blood film of the first drop of blood from the ear lobe appears to be a useful procedure in routine investigation of patients who may have septicæmia.