Gaucher Cells or Pseudo-Gaucher Cells: That’s the Question

To the Editor, Bone marrow cells with morphological characteristics similar to Gaucher cells and without cytoplasmic crystalline inclusions are rare. These Gaucher-like or pseudo-Gaucher cells can be seen in a variety of conditions such as acute lymphoblastic leukemia, multiple myeloma, myelodysplasia, Hodgkin’s disease, thalassemia, and disseminated mycobacterial infection [1,2,3,4,5,6,7,8]. Since the presence of these cells may obscure neoplastic cells in multiple myeloma and may lead to misdiagnosis, it is important for hematologists and hematopathologists to be aware of such a condition in order to make a prompt and accurate diagnosis. Herein we report a case of multiple myeloma in which the presence of plasma cells was missed on initial histological diagnosis. A 44-year-old female without history of any previous systemic disease presented with oliguria, easy fatigability, and breathlessness for 7 days. On examination she had crepitating rales, jugular venous congestion, abdominal distension, and pretibial edema. The complete blood count showed Hb of 67 g/L, WBC count of 3.4x109/L, and platelet count of 69x109/L. Erythrocyte sedimentation rate was 112 mm/h. Bone marrow aspirate and biopsy were performed. The bone marrow aspirate revealed numerous large cells with plentiful cytoplasm and a small eccentric nucleus. Scattered among these were plasma cells, which were obscured by sheets of Gaucher-like cells (Figure 1A). Immunohistochemical staining of bone marrow biopsy showed that plasma cells were positive for CD38 and kappa light chain (Figures 1B and 1C), and the large cells were positive for CD68 (Figure 1D). There were crystalline inclusion bodies within these cells, which were negative for smooth muscle actin, HHF-35, and keratin. The erythroid and myeloid series were normal. Serum electrophoresis revealed an M band. Skull X-ray showed lytic bone lesions. Taken together, a diagnosis of multiple myeloma associated with a prominent pseudo-Gaucher histiocytic response was made.