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Abstract Background Diagnosis of primary immunodeficiencies (PIDs) is complex and cumbersome yet important for the clinical management of the disease. Exome sequencing may provide a genetic diagnosis in a significant number of patients in a single genetic test. Methods In May 2013, we implemented exome sequencing in routine diagnostics for patients suffering from PIDs. This study reports the clinical utility and diagnostic yield for a heterogeneous group of 254 consecutively referred PID patients from 249 families. For the majority of patients, the clinical diagnosis was based on clinical criteria including rare and/or unusual severe bacterial, viral, or fungal infections, sometimes accompanied by autoimmune manifestations. Functional immune defects were interpreted in the context of aberrant immune cell populations, aberrant antibody levels, or combinations of these factors. Results For 62 patients (24%), exome sequencing identified pathogenic variants in well-established PID genes. An exome-wide analysis diagnosed 10 additional patients (4%), providing diagnoses for 72 patients (28%) from 68 families altogether. The genetic diagnosis directly indicated novel treatment options for 25 patients that received a diagnosis (34%). Conclusion Exome sequencing as a first-tier test for PIDs granted a diagnosis for 28% of patients. Importantly, molecularly defined diagnoses indicated altered therapeutic options in 34% of cases. In addition, exome sequencing harbors advantages over gene panels as a truly generic test for all genetic diseases, including in silico extension of existing gene lists and re-analysis of existing data.

Non-transferrin-bound iron and its labile (redox active) plasma iron component are thought to be potentially toxic forms of iron originally identified in the serum of patients with iron overload. We compared ten worldwide leading assays (6 for non-transferrin-bound iron and 4 for labile plasma iron) as part of an international inter-laboratory study. Serum samples from 60 patients with four different iron-overload disorders in various treatment phases were coded and sent in duplicate for analysis to five different laboratories worldwide. Some laboratories provided multiple assays. Overall, highest assay levels were observed for patients with untreated hereditary hemochromatosis and β-thalassemia intermedia, patients with transfusion-dependent myelodysplastic syndromes and patients with transfusion-dependent and chelated β-thalassemia major. Absolute levels differed considerably between assays and were lower for labile plasma iron than for non-transferrin-bound iron. Four assays also reported negative values. Assays were reproducible with high between-sample and low within-sample variation. Assays correlated and correlations were highest within the group of non-transferrin-bound iron assays and within that of labile plasma iron assays. Increased transferrin saturation, but not ferritin, was a good indicator of the presence of forms of circulating non-transferrin-bound iron. The possibility of using non-transferrin-bound iron and labile plasma iron measures as clinical indicators of overt iron overload and/or of treatment efficacy would largely depend on the rigorous validation and standardization of assays.

Background and Objectives In follicular lymphoma histological grading is used to predict clinical behavior and to stratify patients for treatment. However, the reproducibility of histological grading is poor and the clinical significance of the difference between grade 1 and grade 2 follicular lymphoma is unclear. Data on proliferation characteristics with respect to prognosis in follicular lymphoma are inconsistent.Design and Methods We assessed the Proliferation Index in follicles, using Mib-1 immunohistochemical staining in lymph node biopsies from 51 patients with follicular lymphoma who were receiving uniform first-line treatment consisting of cyclophosphamide, vincristine, prednisone and interferon α2b.Results The median Proliferation Index was 16.9 (range 3.1–49.2). In grades 1 and 2 follicular lymphoma (n=45) it was 16.1, compared to 24.2 in grade 3 (n=6; p=0.02). At a median follow-up of 71 months, patients with a Proliferation Index below the median had a significantly prolonged time to progression (median not reached vs. 15 months for those with a Proliferation Index above the median; p =0.0006) and improved overall survival (median not reached vs. 42 months, respectively; p =0.002). In multivariate analysis, the Proliferation Index retained its predictive value. Additional prognostic information was especially provided in patients with a low International Prognostic Index. Histological grade did not predict outcome.Interpretation and Conclusions The Proliferation Index is a biological marker that is strongly and independently predictive for outcome in follicular lymphoma, as shown even in this relatively small series of patients. It is easily applicable and reproducible and therefore superior to histological grading in identifying clinically aggressive follicular lymphoma, requiring other types of treatment.