Haemolysis in typhoid fever in children with G-6-PD deficiency.

MMICAJmJOURNAL Summary Evidence is presented that a cytopathic agent isolated from human nose, throat, and bronchial swabs, and termed " Ryan virus" is in fact an amoeba of the genus Hartmannella. Detection of a protozoal cell-type by electron microscopy led to the recognition of typical trophozoites and cysts of this free-living soil amoeba in inoculated tissue cultures. Details are given of cytopathic effects due to the amoebae, involving primarily the nuclei in cell cultures. It is probable that amoebae do occur in the nasopharynx in some patients with respiratory illness, and they should not necessarily be regarded as laboratory contaminants. Their clinical significance and pathogenicity for man are at present conjectural. We are indebted to our colleague Dr. D. C. Warhurst for help in identification of the amoebae, which he was able to grow readily, with encystment, on agar plates inoculated with killed Aerobacter aerogens. We are grateful to Dr. Janet Niven for helpful advice and documentation. Our thanks are also due to Dr. Reports in the literature on haemolysis as a complication of typhoid fever are few, and such as do exist stress its rarity