PERSISTENT POLYCLONAL B LYMPHOCYTOSIS: MORFOLOGICAL,IMMUNOLOGICAL, CYTOGENETIC AND MOLECULAR ANALYSIS OF ONE CASE

As far as we know there are not any previous report of Persistent Policlonal B Lymphocytosis (PPBL) in italian patients. We report the case of a heavy smoker female patient aged 43 years, with moderate lymphocytosis diagnosed as having PPBL. Clinically she was asymptomatic, without splenohepatomegaly and ymphoadenomegaly; peripheral blood smear examination showed the presence of binucleated lymphocytes; bone marrow was morphologically normal, with slight lymphocytosis without binucleated cells. Immunophenotype showed: CD19+ 44%; CD5+/CD19+, CD23+, IgG+, IgA+ cells: in the normal range; IgM+cells 60%; IgD+ cells 60%; kappa light chain 34% and lambda light chain 30% positive cells; CD3+ cells 47%; CD4+/CD8+ ratio: 3. The patient was HLA-DR10/DR8. The serum IgM were 520 mg/dl policlonal, IgG 1050 mg/dl, IgA 200 mg/dl. There were anti-EBV antibodies IgG type against the viral capside antigen; DNA analysis of peripheral blood cells by PCR was positive for EBV, using a couple of primers complementary for a specific sequence codifying for LMP. Southern blot analysis of the heavy chain (JH) Ig gene performed on peripheral and marrow blood was negative for presence of clonal population. Amplifications of the major breakpoint region (MBR) and minor cluster region (mcr) of the BCL2/IgH translocation performed by PCR showed three different rearrangements in the MBR and one in the mcr. The molecular-cytogenetic examination with probe WCP3 demonstrated the presence, in 2/53 metaphases, of isocromosome +i(3q). Six months later, after the patient quit smoking, there was an improvement of the hematological data: CD19+ cells decrease to25% and we observed a decrease of serum IgM level. The follow up at twenty-four months, after the patient restarted smoking, showed a new increase of CD19+ cells and in binucleated peripheral blood lymphocytes. The case which we have reported is a typical one among those described in literature, a part from the absence of HLADR7. Long term follow-up is needed to exclude the risk of malignant evolution of disease