**FLOW CYTOMETRY:**

Results: Cell suspension immunophenotypic studies were performed on the bone marrow aspirate and one region was analyzed.

Region 1 represents the small non-complex cells (52% of the events).

VIABILITY: 99%

Antigen | Usual Specificity | % Positive |
---|---|---|

Kappa + | B Cell Subset | 2 |

Lambda + | B Cell Subset | 3 |

Kappa:Lambda Ratio | 0.7 | |

CD19+ | B Cell | 11 |

CD19+/CD5+ | B Cell Subset | 3 |

CD20+ | B Cell | 6 |

CD10+ (Calla) | B Cell Subset | 3 |

Antigen | Usual Specificity | % Positive |
---|---|---|

CD2+ | T Cell | 84 |

CD3+ Total | T Cell | 78 |

CD5+/CD19- | T Cell | 74 |

CD7+ | T Cell | 72 |

CD4+/CD8- | T Helper | 13 |

CD8+/CD4- | C Cytotoxic/Suppressor | 63 |

CD4+/CD8+ | T Cell Subset | 1 |

CD4:CD8 Ratio | T Helper:Suppressor Ratio | 0.2 |

CD16,CD56+/CD3+ | T Cell Subset | 2 |

CD16,CD56+/CD3- | NK Cells | 7 |

Antigen | Usual Specificity | % Positive |
---|---|---|

CD15+ | Myeloid | 4 |

CD34+ | Stem Cell | 4 |

Antigen | Usual Specificity | % Positive |
---|---|---|

CD45+ | Leukocytes | 96 |

HLA DR+ | B, Myeloid, Activated T | 78 |

TdT+ | Lymphoblasts (Myeloblasts) | 2 |

Cyto CD3+ | T Cells | 76 |

CD22+ | 2 |

**Interpretation:**

Flow cytometric immunophenotypic studies reveal an increased population of CD3+ T-lymphocytes (78%). This poulation also showed a low CD4:CD8 ratio (0.2) and strong expression of HLA-DR antigen (78%). These findings are consistent with infectious mononucleosis.