A systematic study of the distribution of intracellular parasites in t
he organs and tissues of mice acutely infected (15 days) with the CL s
train of Trypanosoma cruzi was performed. Almost all tissues and organ
s were parasitized with different intensities, including several epith
elial cell types. In addition to striated, cardiac, and smooth muscles
a very high parasitism of fat cells, pancreas, and genital adnexa was
observed. A smaller number of parasites was found in all other struct
ures studied except in highly vascularized structures such as in the p
enile corpora cavernosa, pulmonary and renal parenchyma, islets of Lan
gerhans, hepatic sinusoids, and in atrial endothelium. This paper also
shows, for the first time in the literature, the parasitism of milky
spots, cornea epithelium, cornea stroma, retroorbital fibroblasts, sem
inal vesicles, and coagulative, Cowper's, urethral, preputial, sebaceo
us anal, and clitoris glands. The results indicated that CL strain is
highly invasive, being able to infect cells derived from the three emb
ryonic layers (ectoderm, mesoderm, and endoderm), suggesting that the
paninfectivity may influence the outcome of immunological and patholog
ical events. (C) 1996 Academic Press, Inc.