Clinically significant newly presenting autoimmune thrombocytopenic purpura in adults: a prospective study of a population-based cohort of 245 patients.

The true incidence and prognosis of autoimmune thrombocytopenic purpura (ITP) in adults is unknown. We present the results of a prospective study in a population-based cohort of newly presenting adults (> or = 16 years) with ITP and platelet count of < 50 x 109/l, which took place between 1 January 1993 and 31 December 1999 in the former Northern Health Region in the UK (population 3.08 million). A total of 245 cases were confirmed by bone marrow examination with a median follow-up of 60 months (range 6-78 months). There were 134 females/111 males (1.2:1). Overall incidence was 1.6 per 105 per annum. Absolute incidence was similar for both sexes, with highest age-specific incidence in those aged > 60 years. Thirty patients (12%) presented with frank bleeding, and 28% were asymptomatic. Forty-five patients (18%) received no treatment, and 135 (55%) received first-line treatment only. Thirty patients (12%) underwent splenectomy. There were four deaths (1.6%) from bleeding and/or the complications of therapy in this cohort, but only one was in the acute phase of the illness. The majority of patients (155 out of 245) achieved remission (platelet count > 100 x 109/l), with a further 59 (24%) in partial remission with no symptoms (platelet count 30-100 x 109/l). This population-based study suggests that the traditional view of adult ITP as being a predominantly chronic disease that preferentially affects females needs to be modified.

Quantification improves the prognostic value of CD38 expression in B-cell chronic lymphocytic leukaemia.

Recent studies have shown that CD38 expressed as a percentage of the antigen positivity can predict prognosis and disease progression in patients with B-cell chronic lymphocytic leukaemia (B-CLL). The present study showed that quantification of CD38 expressed as antibody-binding capacity (ABC) improves the prognostic value of the percentage of CD38 positivity in B-CLL. In a cohort of 81 patients with B-CLL, a level of CD38 expression of > or = 30% and an ABC value of 250 proved statistically valid cut-off points to predict disease progression (% CD38: P=0.0027; ABC: P < 0.0001). There was a positive and significant correlation between the percentage of CD38 expression and ABC (r=0.7; P < 0.0001). There was a better discrimination of survival using ABC rather than percentage CD38 positivity (P < 0.0001 compared with P=0.0027). Only ABC predicted for survival in patients under 60 years of age (P=0.0076) or with stage A disease (P=0.0195). Both percentage CD38 and ABC discriminated between time to first treatment for all patients but only ABC predicted time to treatment for stage A patients (P=0.0004). In conclusion, CD38 positivity is an important prognostic factor in B-CLL. However, quantification of CD38 is superior to the percentage positivity and should be used clinically in conjunction with other variables of predictive value to identify B-CLL patients that are likely to progress.