Looking for ALPS: The value of a combined assessment of biochemical markers.

BACKGROUND: Autoimmune lymphoproliferative syndrome (ALPS) is a rare primary immune disorder caused by defect of the extrinsic apoptotic pathway. The current diagnostic criteria combine clinical features and typical biomarkers but have not been the object of clear international consensus. METHODS: We conducted a retrospective study on pediatric patients who were investigated for autoimmune cytopenia and/or lymphoproliferation at the CHU Sainte-Justine Hospital over 10 years. Patients were screened using the combination of TCRαß+ CD4- CD8- "double negative" (DN) T cells and soluble plasmatic FAS ligand (sFASL). RESULTS: Among the 398 tested patients, the median sFASL and DN T cells were 200 ng/mL and 1.8% of TCRαß+ T cells, respectively. sFASL was highly correlated with vitamin B12 levels. We identified five patients diagnosed with ALPS for whose sFASL and vitamin B12 levels were the more discriminating biomarkers. While ALPS diagnostic criteria had high sensibility, their predictive value remained low. CONCLUSION: sFASL level can efficiently discriminate patients with ALPS when using the appropriate thresholds. Our study highlights the need for an international consensus to redefine the place and threshold of biological biomarkers for ALPS diagnosis.

Innovative Curative Treatment of Beta Thalassemia: Cost-Efficacy Analysis of Gene Therapy Versus Allogenic Hematopoietic Stem-Cell Transplantation.

Seventy-five percent of patients with beta thalassemia (ß-thalassemia) do not have human leukocyte antigen-matched siblings and until recently had no access to a curative treatment. Gene therapy is a promising treatment that can be proposed to these patients. This study estimates its cost and efficacy. In a monocentric retrospective study and cost-efficacy analysis, this study compared the two-year outcomes and costs of patients with ß-thalassemia treated by gene therapy and hematopoietic stem-cell transplantation (HSCT). Grade III and grade IV complications, hospitalizations, and length of stay were extracted from the hospital discharge data. Costs were estimated from hospital accounting information and national cost studies. A total of seven patients with ß-thalassemia treated between 2009 and 2016 were included, of whom four received gene therapy. Patients treated by gene therapy were older and had fewer complications and hospital admissions. Infectious complications were three times more frequent for patients treated with HSCT than for gene therapy. Average costs were €608,086 for patients treated by gene therapy and €215,571 for HSCT. The total cost of the vector was 48% of the total cost of gene therapy. Gene therapy as a curative alternative for patients lacking human leukocyte antigen-matched donors was costlier but resulted in fewer complications than HSCT.