Characterization of Collagen Vascular Disease-Associated Bone Marrow Changes by Morphologic and Immunohistochemical Assessment
K Hunt, M Salama, C Sever, K Foucar. U. of New Mexico, Albuquerque, NM; U. of Utah, Salt Lake City, UT; Pathology Associates of Albuquerque, Albuquerque, NM
Background: Collagen vascular diseases (CVD) are frequent in the differential diagnosis for unexplained cytopenias. Unfortunately, there are a paucity of large studies characterizing the bone marrow findings in CVD, making the diagnosis difficult without substantial clinical history. This study aims to identify associated morphologic and immunohistochemical (IHC) abnormalities in a large series of CVD cases.
Design: 101 cases of CVD and 12 controls were selected. Diagnoses were confirmed with chart review. The following data was collected: CBC, peripheral blood smear morphology, bone marrow aspirate smear, clot and core biopsy morphology, iron stain, and manual quantitation or semi-quantitation of IHC for the following antibodies: CD3, CD20, CD34, CD42b, MPO, Hgb A and CD68. Specifically, ten high power fields were counted and averaged. All morphologic and IHC review was performed in a blinded fashion. The results were compared between patients with CVD and normal controls.
Results: Lymphoid aggregates were identified in 47% (40/85) cases of CVD vs. 42% (5/12) of controls. Lipogranulomas (LG) were identified in 11% (11/101) cases of CVD but were in none of the 13 controls. Sea blue histiocytes (SBH) were found in 6% (6/101) of CVD cases and none of the controls. Bony trabeculae were abnormal in 36% (31/87) of CVD and in 17% (2/12) of controls. Megaloblastic changes (at least mild) were present in 30% (30/101) of CVD cases versus none of the controls. A pseudo-myeloproliferative (MPD) appearance was identified in 5% (5/101) CVD cases versus none of the controls. Quantitation of cell lineages via IHC is listed in figure 1.
Conclusions: Many of the investigated features showed no difference between CVD and control groups. Lymphoid aggregates were common in both groups and immunohistochemical stains showed similar quantitation of various cell types. However LG, bony abnormalities, megaloblastic changes, SBH and pseudo-MPD were more prevalent in the CVD group. These features may be helpful in strengthening suspicion of CVD and triggering further clinical investigation.
Wednesday, March 11, 2009 1:00 PM
Poster Session VI # 205, Wednesday Afternoon