Hypertrophic osteoarthropathy presenting as unilateral cellulitis with successful treatment using pamidronate disodium.

Hypertrophic pulmonary osteoarthropathy is a paraneoplastic syndrome seen in patients with lung cancer. This condition is characterized by the presence of digital clubbing, periosteal thickening, synovial thickening, and severe pain of the affected joints. Other syndromes exhibiting clubbing may or may not have underlying diseases causing their manifestation. An example is primary hypertrophic osteoarthropathy, or pachydermoperiostosis. While clubbing makes up part of the clinical picture in both hypertrophic pulmonary osteoarthropathy and hypertrophic osteoarthropathy, the latter has no underlying disease associations. Rather, primary hypertrophic osteoarthropathy is familial, idiopathic, and has a chronic course often beginning during puberty in males. Secondary hypertrophic osteoarthropathy is an acquired form of clubbing that is classically associated with lung disease. However, it has also been associated with diseases of the heart, liver, and intestines. In the setting of pulmonary malignancy, secondary hypertrophic osteoarthropathy is known as hypertrophic pulmonary osteoarthropathy. Hypertrophic pulmonary osteoarthropathy has a distinct constellation of clinical findings that includes intractable pain often refractory to treatments other than resolution of the underlying disease process. The authors herein report a case of hypertrophic pulmonary osteoarthropathy masquerading as recurrent lower extremity cellulitis with chronic hand and foot pain in the setting of pulmonary malignancy that responded dramatically to intravenous pamidronate disodium (a bisphosphonate). Given the rarity of hypertrophic osteoarthropathy associated with lung cancer and the difficulty with pain management in such circumstances, the authors present the following case in which pain was mitigated by treatment with bisphosphonate therapy.