Treatment with pamidronate reduces pain and reverses damage to the bone in children with treatment-refractory, noninfectious mandibular osteolytic lesions, according to two cases reported by Canadian physicians. Treatment with pamidronate reduces pain and reverses damage to the bone in children with treatment-refractory, noninfectious mandibular osteolytic lesions, according to two cases reported by Canadian physicians in the July issue of the Journal of Rheumatology.

Chronic recurrent multifocal osteomyelitis (CRMO) and diffuse sclerosing osteomyelitis of the mandible (DSOM) can be difficult to treat, note Dr. Sandrine Compeyrot-Lacassagne of the Hospital for Sick Children in Toronto and associates. Bisphosphates have been considered for treatment of these conditions because of their antiresorptive, anti-inflammatory, and analgesic properties.

The two patients had developed symptoms at four and six years of age, according to the article. One was referred to the Hospital for Sick Children after four months, where she was diagnosed with CRMO. A year after symptom onset, and after several rounds of NSAIDs, corticosteroids, and antibiotics, she was treated with pamidronate.

The second child was similarly treated with NSAIDs and corticosteroids after a diagnosis of DSOM. After nine months, and again three years later, she underwent surgical debridement of the bony lesion, but she continued to require daily transdermal opioid analgesia. Five years after her initial presentation, she was referred to the pediatric rheumatic disease program at the University of Saskatchewan, where she began treatment with pamidronate.

The physicians initiated IV pamidronate at a dose of 0.5 mg/kg for the first infusion, which was increased to 1 mg/kg for two more days. Treatment was repeated as needed.

In both cases, pain and swelling resolved within a few days after the first infusion, the authors report. On CT scans performed after about a year, osteolytic changes had resolved, and bone remodeling resulted in nearly normal mandibular size and shape.
One patient developed a new lesion at another site, which was managed with indomethacin. The older child has not required any more surgery, but has undergone repeated courses of pamidronate. After her fourth course, however, further treatment with pamidronate was precluded by treatment-related mouth ulcers, mandibular pain and increased swelling.

In the absence of long-term data for bisphosphate treatment in children, and "given the potential risk of irreversible osteopetrosis, cautious monitoring is warranted when high cumulative doses of pamidronate are administered to the growing skeleton," Dr. Compeyrot-Lacassagne and associates advise.