Quantification of Marrow Plasmacytosis in HIV Patients

Introduction:

A reactive, polyclonal increase in marrow plasma cells in pts with HIV is relatively common, reported to occur in 25% of cases in one series (1) and recently noted to be "usually seen" (2). However, quantification of the degree of marrow plasmacytosis has not been well described.

Methods:

Pts with a diagnosis of HIV and who had a bone marrow aspirate and biopsy performed at our institution over a 10 year period (2/2004-9/2014) were reviewed. Pts with a diagnosis of myeloma were excluded. A 500 cell count was performed on each marrow aspirate and plasma cell percentage determined.

Results:

65 pts were identified; 9 were excluded due to dry taps, so there were 56 evaluable marrow aspirates. Reasons for performing the aspirate and biopsy included: lymphoma staging (NHL in 11/65, HL in 4/65); abnormal SPEP (2/65); abnormal MRI (1/65); FUO (14/65), Kaposi's sarcoma/fevers (3/65), pancytopenia (15/65), thrombocytopenia (6/65), neutropenia (2/65) and anemia (10/65). The average marrow plasma cell percentage was 4.6%, with a range from 0- 21% (median 4%). Only 7/56 (12.5%) had >10% plasma cells. Of these 7 cases, only one had an identifiable cause (multicentric Castleman's) for the plasmacytosis. The 6 others had no neoplastic or infectious etiology, except for HIV itself (including one with 21% plasma cells). All had polyclonal plasmacytosis.

Conclusions:

In this small series of HIV marrows the degree of plasmacytosis was generally mild (average of 4.6%, which is barely above the upper limit of normal range of 3.5%). However, there were a minority of cases which exhibited significant plasmacytosis (as high as 21%) without any cause other than HIV. This suggests that, while significant marrow polyclonal plasmacytosis is usually not seen in HIV, it may occur as a result of HIV itself without any other identifiable cause.

1) Karchen DS and Frost AR. The bone marrow in HIV-related disease: Morphology and clinical correlation. Am J Clin Path. 1991; 95(1): 63-71.

2) Leibman HA and Tulpule A. "Hematologic manifestations of HIV/AIDS". Chapter 159. Hematology: Basic Principles and Practice, 6th edition. 2013.