Typical Gaucher cells have a characteristic “wrinkled tissue paper” appearance of the cytoplasm as a result of deposition of glucocerebroside. These cells can be up to 60 μm in diameter. Some cells have tubular or fibrillary structures in the cytoplasm.1
In the presence of cytopenia related symptoms, hepatosplenomegaly, and typical Gaucher cells in the bone marrow, the diagnosis of Gaucher disease is not difficult. Both patients were normal before the presentation of tuberculosis, and in case 2 there were no abnormal histiocytes in the bone marrow.
Pseudo-Gaucher cells in chronic myelogenous leukaemia resulted from rapid cell turnover with glucocerebroside deposition in the cells. The colour of the cytoplasm in pseudo-Gaucher cells of chronic myelogenous leukaemia is bluer than that in classic Gaucher cells. Pseudo-Gaucher cells in thalassaemia or other haematological malignancies are extremely rare, and are usually presented as case reports.
“Pseudo-Gaucher cells might be the morphological hallmark of mycobacterial infection in immunodeficiency”
Solis et al
reported the first case of pseudo-Gaucher cells in M aviumintracellulare
infection in an HIV infected patient.7
They noted massive infiltration of the lamina propria of the bronchial mucosa, lung parenchyma, and bone marrow with foamy histiocytes. There were numerous needle-like structures in the cytoplasm of the histiocytes. These foamy histiocytes were rounded, 25–30 μm in diameter, and had abundant pale blue cytoplasm and a peripherally displaced nucleus. They noted that granulomas are poorly formed with no lymphoplasmacytic reaction. Later, Links et al
reported another case of tuberculosis with pseudo-Gaucher cells. This patient had pulmonary tuberculosis (sputum culture grew M tuberculosis
) with fatal respiratory failure, and the HIV status was unknown.8
At necropsy, pleural culture revealed M tuberculosis
. Large foamy histiocytes with numerous needle-like structures infiltrated the liver, bone marrow, lymph nodes, spleen, and lungs. Special stains for AFB and fungi and periodic acid Schiff staining of these organs were negative. Both patients died shortly after diagnosis. In our studies, pseudo-Gaucher cells were smaller than typical Gaucher cells. Periodic acid Schiff staining of these cells was negative in contrast to a strongly positive reaction in typical Gaucher cells. There was no “wrinkled paper appearance” in the cytoplasm—the characteristic findings of Gaucher cells. Thus, it is not difficult to differentiate these cells from classic Gaucher cells by microscopy. In our patients, only histiocytes infected by AFB had a Gaucher-like cell appearance. Therefore, pseudo-Gaucher cells may result from inadequate digestion of mycobacterial bacilli by histiocytes. Both patients were in an immunodeficient state, with poor function of histiocytes.
Take home messages
- We describe two immunocompromised hosts (one with AIDS and the other an alcoholic) with mycobacterial infection
- Pseudo-Gaucher cells were found in the bone marrow and lymph nodes of these patients, respectively
- These pseudo-Gaucher cells contained needle-like inclusions and acid fast bacilli
- A diagnosis of mycobacterial infection in immunodeficiency should be suspected in the presence of psuedo-Gaucher cells
In conclusion, pseudo-Gaucher cells might be the morphological hallmark of mycobacterial infection in immunodeficiency. In the presence of pseudo-Gaucher cells, AFB stains should be performed immediately and antituberculosis regimens should be prescribed if the result is positive. However, the presence of pseudo-Gaucher cells might predict a very poor outcome.