In the recent past, enormous changes in the management of malignant di
seases and the emergence of AIDS have resulted in the appearance of ex
otic and unusual organisms as causative agents of infection in the imm
unocompromised patient. in addition, causative organisms for a range o
f diseases associated with this group of patients whose aetiology had
not previously been established have been found. This review focuses o
n some of the features of these infections, and summarizes the develop
ments of new and unusual therapies for the management of infection in
this group of patients.