Osteoporosis with lymphoid nodules and hematopoietic marrow hyperplasia.

Objective: In 1983 Vigorita reported 3 cases of osteoporosis associated with intramedullary lymphoid nodules. We present 8 patients with osteoporosis and lymphoid nodules (LN) in whom we studied the clinical, biological and histological features and the course of the disease.

Methods: Three men (mean age 52 yrs., range 43-68 yrs.) and 5 women (mean age 60 yrs., 49-66 yrs.), 6 of them with osteoporosis with fracture and 2 with osteoporosis on bone densitometry (T score < -2.5 SD) were enrolled in this study. The following parameters were studied: immunobinding with IG determination, phosphorus and calcium levels, PTH, 25 and 1-25 OH D3, osteocalcin, urinary deoxypyridinoline, histomorphometry, tests for autoanti-bodies, HIV, HTLV, EBV and CMV serology. The results were compared with those of 20 patients with osteoporosis but without LN. Five patients underwent a second BMB a mean of 2 years after the first.

Results: Five patients had asthenia, 4 had joint pain and 3 had hyperlymphocytosis. Immunologic and virologic investigations were negative in all cases. Bone marrow was hypercellular (59.9 +/- 5.3 vs 40.1 +/- 13%, p: 0.001). At the second BMB, LN were absent but bone marrow was still hypercellular. In all cases, no cause of demineralization was found and osteoporosis progressed rapidly (an average of 3 vertebral compression fractures in three months, with increased resorption (ES 6.5 +/- 1.6 vs 3 +/- 1.2, p: 0.05) with decreased calcification rate (CR 0.62 +/- 0.07 vs 0.79 +/- 0.1, p: 0.04).

Conclusion: Some interesting questions are raised by this study. Did an undiscovered viral infection cause the asthenia and joint pain via cytokines or PTHrp in our patients, and can activated lymphocytes perhaps modify bone remodeling?