Utility of testing for monoclonal bands in serum of patients with suspected osteoporosis: retrospective, cross sectional study.

OBJECTIVE: To determine whether measuring monoclonal bands (M component) in serum should be part of the investigation of patients referred to osteoporosis clinics. DESIGN: Retrospective, cross sectional, observational study. SETTING: Referral centre for osteoporosis in a university hospital, Denmark. PARTICIPANTS: 799 people (685 women) aged 19 to 94 years newly referred with suspected osteoporosis. MAIN OUTCOME MEASURES: Proportion of patients fulfilling the Nordic Myeloma Study Group definition for target condition and proportion of patients with other important haematological conditions. RESULTS: 4.9% (18 of 366) of patients with osteoporosis and 2.2% (9 of 408) of patients without osteoporosis had M component in serum (chi2 = 3.66, P = 0.04). Multiple myeloma was diagnosed in three patients with osteoporosis (absolute risk 0.8%, 95% confidence interval 0.11% to 1.7%). The relative risk of multiple myeloma in patients presenting with osteoporosis was 75 (10 to 160). As a diagnostic test for multiple myeloma in patients with osteoporosis, M component in serum had a specificity of 95.0% and a positive predictive value of 17.6%. 122 blood electrophoreses were carried out for each case of multiple myeloma diagnosed. All patients with multiple myeloma had a history of fragility fractures. If lymphoma was included as a target condition, the specificity increased to 95.3% and the positive predictive value increased to 23.5%. Monoclonal gammopathy of undetermined significance was diagnosed in 13 (3.6%) participants with osteoporosis and in eight (2.0%) participants with normal bone mineral density or osteopenia. CONCLUSIONS: Patients presenting with osteoporosis should be tested for M component in serum, as 1 in 20 patients with newly diagnosed osteoporosis had multiple myeloma or monoclonal gammopathy of undetermined significance.

Rituximab chimeric anti-CD20 monoclonal antibody treatment for adult refractory idiopathic thrombocytopenic purpura.

Idiopathic thrombocytopenic purpura is an autoimmune disease which involves opsonization of platelets by autoantibodies directed against different surface glycoproteins, leading to their premature destruction by the reticuloendothelial system. Management of patients with refractory ITP is difficult. Recent studies have shown that rituximab, a chimeric anti-CD20 monoclonal antibody, is useful in the treatment of these patients, with overall response rates of about 50%. Most published reports have included a small number patients including case reports. The present study reports the results of a retrospective Danish multicenter study of rituximab in the treatment of adult patients with refractory ITP. Thirty-five patients (median age 52 years, range 17-82 years, 17 males) were included. One patient had immune thrombocytopenia and neutropenia. All patients had received prednisolone (Pred). Next to Pred, 25 patients had been treated with high-dose IgG, and in 16 patients a splenectomy had been performed. Sixteen patients had been treated with azathioprine. Other treatments included, e.g., cyclosporine, danazol, cyclophosphamide, vincristine, interferon, and dexamethasone. The patients were treated with a dose regimen of 375 mg/m2 i.v. approximately once weekly for 4 consecutive weeks. Six patients received a fixed dose of 500 mg disregarding their weight supplemented by 100 mg of methylprednisone i.v. or 50-100 mg of Pred given as premedication together with an antihistamine just before infusion of rituximab. The large majority of patients also received Pred and, in some cases, other concomitant immunosuppressive treatment during part of their rituximab treatment. A complete response (CR) was defined as a rise in the platelet count > 100 x 10(9)/L, a partial response (PR) as a rise in the platelet count > 50 x 10(9)/L, and a minor response (MR) as a rise in the platelet count < 50 x 10(9)/L. No response (NR) was defined as no increase in the platelet count. Because 4 patients were treated twice, a total of 39 outcomes of rituximab treatment were evaluated. Rituximab proved to be effective in 17 of 39 treatments [overall response 44% with 7 CR (18%) (1 patient showed a CR twice), 6 PR (15%), and 4 MR (10%)]. In 9/13 cases of CR or PR, the response (platelet level > 50 x 10(9)/L) was prompt, 1-2 weeks after the first infusion. The remaining patients responded 3-8 weeks later. Patients with CR and PR have been in remission for a median of 47 weeks. In general the side effects were few. In 2 cases, the treatment was stopped because of side effects either during or after the first infusion. Two fatal outcomes were recorded. A 71-year-old female with severe lung disease died 6 days after the first infusion of respiratory failure. The other patient, a 73-year-old man also with severe chronic obstructive lung disease, died of pneumonia approximately 13 weeks following the last rituximab treatment. It is concluded that rituximab may be a useful alternative therapy in patients with severe and symptomatic ITP refractory to conventional treatment.