EC Dental Science

Mycobacterial spindle cell pseudotumor is an exceptionally encountered, benign neoplasm composed of spindle shaped cells. The infrequently discerned disease is engendered due to a response towards mycobacterial infection. Initially scripted by Wood., et al. in 1985, cutaneous mycobacterial spindle cell pseudotumour may simultaneously arise within several sites. Of inflammatory histogenesis, mycobacterial spindle cell pseudotumour commonly arises within subjects infected with human immunodeficiency virus (HIV), infants following BCG vaccination and post-transplant recipients. Neoplasm is preponderantly comprised of spindle shaped cells which are pre-eminently macrophages impregnated with significant quantities of Mycobacteria. The innumerable intracellular organisms may be suitably detected by intraoperative touch imprint preparations. Demonstrating a male predominance with male to female proportion of ~5:1, an estimated 50% subjects demonstrate infection with human immunodeficiency virus (HIV) infection [1,2]. Commonly, tumefaction is confined to lymph node, various cutaneous sites and soft tissue. Mycobacterium avium complex is a commonly encountered (~47%) mycobacterium engendering the lesions followed in frequency by Mycobacterium tuberculosis complex (~16%). Mycobacterial spindle cell pseudotumour may occur due to a dysregulated immune response with consequent proliferation of spindle shaped cells. Therefore, conditions such as infection with human immunodeficiency virus (HIV) with accompanying immunocompromised state appear to contribute to disease emergence [1,2]. Tumefaction is associated with clinical symptoms as progressive swelling of the digit, configuration of nodules and linear lymph node enlargement. Inflammatory genesis of the neoplasm may be confirmed by flow cytometry and diverse staining techniques. Cytological examination depicts proliferation of spindle shaped cells simulating Kaposi’s sarcoma. An absence of foamy histiocytes is encountered [2,3]. Upon microscopy, lymph nodes display partial or comprehensive effacement of lymph node architecture. The dermis may represent with configuration of tumour nodules [2,3].

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9. Coelho R., et al. “Mycobacterium genavense-induced spindle cell pseudotumor in a pediatric hematopoietic stem cell transplant recipient: case report and review of the literature”. Transplant Infectious Disease 2 (2017).
10. Image 1 Courtesy: Basic medical key.
11. Image 2 Courtesy: BMJ Case Reports.