Heterogeneous gonocytes include foamy, irregular and naive types. Foamy cells are slightly larger than lymphocytes and are round or oval in shape, some are irregular in shape, and the nucleus is deviated and round, kidney-shaped or irregular. The irregular type is larger than the foam type, and the cell shape is often irregular, resembling mononuclear cells, so it is also called mononuclear cell type. The naive type has large cytosol, round or oval, with a large amount of cytoplasm, blue or dark blue, usually without granules, and sometimes with a few small vacuoles. Heterogeneous gonocytosis is mainly seen in infectious mononucleosis, early epidemic hemorrhagic fever, and viral infections such as viral hepatitis, rubella, measles, mumps, and encephalitis B.