Lymphocyte Aggregation in Low-Grade B-Cell Lymphoma

Abstract

Platelet and erythrocyte agglutination is known to happen in vitro due to EDTA or temperature-induced cold antibodies. Leukocyte agglutination is far less common, and its etiology is not always known. The 2 cases presented herein are of low-grade B-cell lymphomas consistent with splenic marginal-zone lymphoma that presented with lymphocyte agglutination. In Case A, the lymphocyte aggregates were not resolved by warming the sample or by non-EDTA anticoagulation. In Case B, the lymphocyte aggregates were largely resolved by warming the specimen at 37°C for 15 minutes. The 2 cases presented herein further show that the etiology of lymphocyte aggregation can have multiple causes, even within the same disease process.

Unreliable Automated Complete Blood Count Results: Causes, Recognition, and Resolution

“…WBC clumping is an infrequently observed phenomenon that may involve one or more cell types [ 19 - 22 ]. The cell clumps are often too large to be counted, yielding a falsely lower WBC count.…”

“…Clumps of granulocytes ( Fig. 3 ) have occasionally been observed in the blood smears of patients with infection, cirrhosis, autoimmune disorder, uremia, immunosuppression, or various malignancies [ 21 - 26 ]. Clumps of lymphocytes have occasionally been observed in the blood smears of patients with lymphoproliferative disorders [ 21 , 22 ].…”

“…c. Incubate the EDTA-anticoagulated blood specimen at 37°C for 10 min and rerun the analysis [ 20 , 22 , 23 ].…”

“…3) have occasionally been observed in the blood smears of patients with infection, cirrhosis, autoimmune disorder, uremia, immunosuppression, or various malignancies [21][22][23][24][25][26]. Clumps of lymphocytes have occasionally been observed in the blood smears of patients with lymphoproliferative disorders [21,22]. The cause of WBC clumping may be multifactorial, including the presence of leukoagglutinins, which may be cold-reactive (at temperatures < 37°C) and/or EDTA-dependent [19,[22][23][24][25][26][27].…”

“…Clumps of lymphocytes have occasionally been observed in the blood smears of patients with lymphoproliferative disorders [21,22]. The cause of WBC clumping may be multifactorial, including the presence of leukoagglutinins, which may be cold-reactive (at temperatures < 37°C) and/or EDTA-dependent [19,[22][23][24][25][26][27]. To obtain reliable results, one may attempt any or all of the following approaches because none of them yields reliable results in all cases [19][20][21][22][23][24][25][26][27].…”