Torg-Winchester syndrome: lack of efficacy of pamidronate therapy

Torg-Winchester syndrome, which includes nodular arthropathy with osteolysis (OMIM 605156), is a condition associated with generalized osteoporosis. On the basis of usefulness of pamidronate in conditions with osteoporosis, we hypothesized that the drug will improve osteolysis and/or osteoporosis in this condition. After obtaining informed consent from the parents, two siblings affected with Torg-Winchester syndrome were administered intravenous pamidronate over a period of 3 years. The clinical status was monitored along with the bone mineral density (using radiographs and X-ray densitometry) to assess the effect of the drug. Clinically there was no improvement. Although the bone mineral density improved in axial skeleton, osteoporosis and osteolysis continued to worsen in the appendicular skeleton. We conclude that pamidronate does not improve peripheral osteolysis in multicentric osteolysis and nodular arthropathy caused by mutation in matrix metalloproteinase 2 gene.