Here’s a case that involves a very pretty cell. Once you know what this cell is, you won’t forget it – it’s that unusual and memorable!  If you want to test yourself with other unknown cases, here are some to try:
- Case 1: 20-year-old male who died suddenly
- Case 2: 72-year-old male with right calf mass
- Case 3: 67-year-old female with pancytopenia
- Case 4: 59-year-old male with severe headaches
- Case 5: 38-year-old female with deep venous thrombi
- Case 6: 13-year-old male with cerebellar mass
- Case 7: 45-year-old male with pulmonary emphysema
- Case 8: 38-year-old male with AIDS and headaches
- Case 9: 25-year-old male with arm mass
Back to this case. Take a look at the photo and the question, then scroll down for the answer.
A 57-year-old male presents with fatigue and left upper quadrant heaviness. His white blood cell count is 110 x 109/L, and his hemoglobin is 8 g/dL. A bone marrow biopsy is performed, and in addition to a marked increase in neutrophils and precursors, a rare cell such as the one depicted here is present. What is this cell?
A. Malignant plasma cell
B. Megakaryocyte
C. Metastatic carcinoma cell
D. Pseudo-Gaucher cell
E. Stromal cell
(Scroll down for the answer)
This cell is a pseudo-Gaucher cell, a histiocyte with pale blue, needle-like inclusions, which resembles the foamy, glucocerebroside-stuffed macrophage characteristic of Gaucher disease. Here is a real Gaucher cell:
 
Back to the pseudo-Gaucher cell. Pseudo-Gaucher cells are occasionally seen in chronic myeloid leukemia, as was the case in this patient (you might have guessed that the patient had CML from the fatigue, splenomegaly, and massive leukocytosis with neutrophilia). They have also been described in other various hematologic disorders, such as myeloma, lymphoma, myelodysplastic syndromes, and thalassemia.
Thank you very much for your time and willingness to share with us all these beautiful information!
I have a question about the difference between histiocytes and macrophages: is there really any difference? I’ve been told that it’s the same BUT when it comes for thyroid I should use “macrophages” and when it comes for breast I should use “foamy histiocytes”. Why is that? It’s a bit complicated…
Hi Christina –
“Histiocyte” and “macrophage” are the same thing. I am not sure why you would restrict one term to certain tissues; you can really use the terms interchangeably. One time you might want to use the word histiocyte instead of macrophage is after the word “foamy,” as you suggested. For some reason, “foamy macrophages” is not used much (though it would mean exactly the same thing). Some sources say you should use the term “histiocyte” when a macrophage is present in connective tissue – but in practice, the terms are generally used interchangeably. There are specialized macrophages/histiocytes that exist in different tissues and have different markers on their surfaces – dendritic cells in the skin/lymph nodes, Kupffer cells in the liver, dust cells in the lung.
Thank you so much! You are a treasure! God bless you.
I always thought that “macrophage” was a term specific for monocitic differentiation coming from the blood and “histiocyte” a more generic term that account for the many kinds of APC like dendritic cell, Kuppfer and so on. Thank you for elucidating my doubts!
I know what you’re saying… I think it depends on the source you read. I did a quick lit search and couldn’t get a consensus on that. My understanding from a practical standpoint is that you call it a monocyte when it’s in the blood, and a macrophage outside of the blood (in tissues). There are specialized cells of the reticuloendothelial system depending on where you are in the body – and these may have different cell surface markers. However, they perform similar functions (phagocytosis, antigen presentation, etc.). I hope that helps!
i am a pathology professor somewhere in the far east and is especially proud that someone can still make a site like this to help students learn pathology the easier way. all best for you Dr. Kristine.
thank u…