Rapamycin Controls Lymphoproliferation and Reverses T-Cell Responses in a Patient with a Novel STIM1 Loss-of-Function Deletion.

PURPOSE: Deficiency of stromal interaction molecule 1 (STIM1) results in combined immunodeficiency accompanied by extra-immunological findings like enamel defects and myopathy. We here studied a patient with a STIM1 loss-of-function mutation who presented with severe lymphoproliferation. We sought to explore the efficacy of the mTOR inhibitor rapamycin in controlling disease manifestations and reversing aberrant T-cell subsets and functions, which has never been used previously in this disorder. METHODS: Clinical findings of the patient were collected over time. We performed immunological evaluations before and after initiation of rapamycin treatment, including detailed lymphocyte subset analyses, alterations in frequencies of circulating T follicular helper (cTFH) and regulatory T (Treg) cells and their subtypes as well as T cell activation and proliferation capacities. RESULTS: A novel homozygous exon 2 deletion in STIM1 was detected in a 3-year-old girl with severe lymphoproliferation, recurrent infections, myopathy, iris hypoplasia, and enamel hypoplasia. Lymphoproliferation was associated with severe T-cell infiltrates. The deletion resulted in a complete loss of protein expression, associated with a lack of store-operated calcium entry response, defective T-cell activation, proliferation, and cytokine production. Interestingly, patient blood contained fewer cTFH and increased circulating follicular regulatory (cTFR) cells. Abnormal skewing towards TH2-like responses in certain T-cell subpopulations like cTFH, non-cTFH memory T-helper, and Treg cells was associated with increased eosinophil numbers and serum IgE levels. Treatment with rapamycin controlled lymphoproliferation, improved T-cell activation and proliferation capacities, reversed T-cell responses, and repressed high IgE levels and eosinophilia. CONCLUSIONS: This study enhances our understanding of STIM1 deficiency by uncovering additional abnormal T-cell responses, and reveals for the first time the potential therapeutic utility of rapamycin for this disorder.

Hematopoietic stem cell transplantation activities and HRQOL of refugee or asylum seeker children in Turkey: A multicenter study.

BACKGROUND: Refugee or asylum seekers (RAS) children are at increased risk of physical, developmental, and behavioral health issues. The aim of this study was to evaluate clinical and psychosocial outcomes of hematopoietic stem cell transplantation (HSCT) in RAS children and compare health-related quality of life (HRQOL) to those of Turkish peers. METHODS: This retrospective study included patients who underwent HSCT aged 0-18 years and completed 100-day post-transplant. The PedsQL 4.0 Generic Core Scale was used in children over 5 years old to compare HRQOL. RESULTS: A total of 166 RAS patients (M/F: 106 /60) underwent 174 HSCTs (six patients had two, and one had three HSCT) compared to 66 Turkish patients. The mean age of the patients in the RAS group was 7.8 ± 4.9 years and similar to controls. A total of 124 patients (75%) were from Syria, and 49 (25%) were from other countries in the Middle East and Africa. The cause of migration was war in 121 (74%) RAS patients. Complications of HSCT were no different between the groups. However, the rate of neutropenic sepsis was significantly higher in the RAS group (p = 0.004). The total scores of HRQOL were not different between RAS and controls. In the RAS group, ratings of social functioning were lower in patients with consanguinity or non-malignant disease or who had match-related donors. DISCUSSION: Identifying areas of difficulty in subscales of HRQOL may help physicians to classify patients who need additional supportive care. Regular monitoring and supporting physical needs may result in better functional outcomes after HSCT.

Clinical and Laboratory Factors Affecting the Prognosis of Severe Combined Immunodeficiency.

PURPOSE: Severe combined immunodeficiency (SCID) is one of the most severe forms of inborn errors of immunity characterized by absence or loss of function in T cells. The long-term outcomes of all forms of SCID have been evaluated in a limited number of studies. We aimed to evaluate the pre- and post-transplant manifestations of SCID patients and determine the factors affecting the survival of patients. METHODS: We included 54 SCID patients (classical SCID, Omenn syndrome, atypical SCID (AS)) in this study. We evaluated the clinical presentation, infections, and outcome of hematopoietic stem cell transplantation (HSCT). Lymphocyte subsets and T-cell receptor (TCR) repertoire were analyzed by flow cytometry. RESULTS: The median age at diagnosis was 5 (range: 3-24) months and follow-up time was 25 (range: 5-61) months. Symptom onset and diagnostic ages were significantly higher in AS compared to others (p = 0.001; p < 0.001). The most common SCID phenotype was T-B-NK + , and mutations in recombination-activating genes (RAG1/2) were the prominent genetic defect among patients. The overall survival (OS) rate was 83.3% after HSCT, higher than in non-transplanted patients (p = 0.001). Peripheral blood stem cell sources and genotypes other than RAG had a significant favorable impact on CD4+ T cells immune reconstitution after transplantation (p = 0.044, p = 0.035; respectively). Gender matching transplantations from human leukocyte antigen (HLA)-identical and non-identical donors and using peripheral blood stem cell source yielded higher B-cell reconstitution (p = 0.002, p = 0.028; respectively). Furthermore, receiving a conditioning regimen provided better B-cell reconstitution and chimerism (p = 0.003, p = 0.001). Post-transplant TCR diversity was sufficient in the patients and showed an equal distribution pattern as healthy controls. The OS rate was lower in patients who underwent transplant with active infection or received stem cells from mismatched donors (p = 0.030, p = 0.015; respectively). CONCLUSION: This study identifies diagnostic and therapeutic approaches predictive of favorable outcomes for patients with SCID.

Haploidentical hematopoietic stem cell transplantation with post-transplant high-dose cyclophosphamide in high-risk children: A single-center study.

BACKGROUND: Post-Cy administration for GVHD prophylaxis in unmanipulated haploidentical HSCT has resulted in improved outcomes in recent years. Studies in children are lacking and accordingly we present the outcomes of 62 haploidentical transplantation for high-risk children. PROCEDURE: We retrospectively assessed 62 transplants in 60 patients who underwent haploidentical-related HSCT with unmanipulated stem cells and for whom Post-Cy was used for GVHD prophylaxis. RESULTS: Myeloid reconstitution was achieved on day + 30 for 57 of the 62 patients. The median follow-up of the surviving 39 patients (63%) was 26 months, with a range of 6-57 months. The OS and EFS at 2 years were 64.6% (52.0%-77.2%, 95% CI) and 58.9% (46.1%-71.7%, 95% CI), respectively. The only factor in our multivariate analysis that contributed to an inferior EFS was a poor remission status prior to HSCT (HR, 8.30; 1.08-63.56; P = 0.041, 95% CI). CONCLUSION: The results of T-cell replete haploidentical transplantation with Post-Cy GVHD prophylaxis in high-risk pediatric patients are promising. However, further research is needed to determine the factors that have affect HLA compatibility for predicting the success of haploidentical transplantations.

High Infection-Related Mortality in Pediatric Acute Myeloid Leukemia without Preventive Antibiotics and Antifungals: Retrospective Cohort Study of a Single Center from a Middle-Income Country.

OBJECTIVE: This study aimed to evaluate infection-related mortality in patients with acute myeloid leukemia (AML) treated without preventive antibiotics and antifungals in a middle-income country. MATERIALS AND METHODS: Infection-related mortality was evaluated retrospectively in 49 pediatric patients. RESULTS: A total of 173 chemotherapy courses were administered as first-line chemotherapy. Four patients died during induction: one patient due to intracranial bleeding, two patients due to typhlitis, and one patient due to invasive fungal infection with pulmonary vascular invasion and massive bleeding. Another two patients died with resistant disease. During consolidation there were four infection-related deaths and one death due to cardiotoxicity. In first-line chemotherapy mortality was 22% (11/49); infection-related mortality was 14% (7/49). Event-free survival and overall survival at 6 years were 42.9% and 61.2% (95% CI: 44-76 and 66-99 months), respectively. CONCLUSION: Due to considerable infection-related deaths, antibacterial and mold-active antifungal prophylaxis may be tried during neutropenic periods in pediatric AML.

Screening bleeding disorders in adolescents and young women with menorrhagia.

OBJECTIVE: Chronic menorrhagia causes anemia and impairment of life quality. In this study the aim was the screening of bleeding disorders in adolescents and young women with menorrhagia. MATERIALS AND METHODS: The study was performed prospectively by pediatric hematologists. A form including demographic characteristics of the patients, bleedings other than menorrhagia, familial bleeding history, characteristics of the menorrhagia, and impairment of life quality due to menorrhagia was filled out by the researcher during a face-to-face interview with the patient. A pictorial blood assessment chart was also used for evaluation of blood loss. All patients underwent pelvic ultrasound sonography testing and women also received pelvic examination by gynecologists. Whole blood count, peripheral blood smear, blood group, serum transaminases, urea, creatinine, ferritin, PFA-100, PT, aPTT, INR, TT, fibrinogen, VWF:Ag, VWF:RCo, FVIII, and platelet aggregation assays were performed. Platelet aggregations were studied by lumiaggregometer. RESULTS: Out of 75 patients enrolled, 60 patients completed the study. The mean age was 20.68±10.34 (range: 10-48) years and 65% (n=39) of the patients were younger than 18 years. In 18 (46%) of the adolescents, menorrhagia subsided spontaneously. In 20% (n=12) of the patients, a bleeding disorder was detected (1 case of type 3 von Willebrand disease, 2 patients with low VWF:Ag, 1 case of probable von Willebrand disease, 3 cases of Bernard-Soulier syndrome, 2 cases of Glanzmann thrombasthenia, 2 cases of immune thrombocytopenic purpura, 1 case of congenital factor VII deficiency). CONCLUSION: In patients with menorrhagia, at least complete blood count, peripheral smear, aPTT, PT, VWF:Ag, VWF:RCo, FVIII, and fibrinogen assays must be performed. When there is history of nose and gum bleeding, platelet function assay by lumiaggregometer must also be performed. In nearly 50% of adolescents, menorrhagia is dysfunctional and transient. Detailed coagulation assays can be postponed in adolescents if bleeding history other than menorrhagia and/or family history of bleeding and/or parental consanguinity is absent. All subjects with menorrhagia must consult with gynecologists and hematologists. CONFLICT OF INTEREST: None declared.

Management of autoimmune hemolytic anemia in children and adolescents: A single center experience.

OBJECTIVE: To present and discuss the treatment of autoimmune hemolytic anemia (AIHA). METHODS: The medical records of all patients (n=19) diagnosed in a tertiary hematology center between 1999 and 2010 were retrospectively reviewed. RESULTS: Median age at diagnosis of AIHA was 5 years (range: 4 months-17 years). In all, 13 patients had primary (idiopathic) AIHA, whereas 2 had primary Evans Syndrome (ES), 2 had autoimmune lymphoproliferative syndrome (ALPS)+ES, and 1 had Wiskott-Aldrich syndrome (WAS)+AIHA. Among the 13 primary idiopathic AIHA patients, 9 recovered following a 4-8-week course of prednisolone treatment without relapses, whereas 3 patients required a longer course of prednisolone. One AIHA patient that was very resistant to prednisolone recovered after cyclosporine A was added to the treatment. All patients with primary idiopathic AIHA were in remission for a median of 3 years (range: 4 months-10 years) at the time this manuscript was written. Among the patients with primary ES, 2 had relapses similar to the ALPS patients. Splenectomy was performed in 1 primary ES patient, who at the time this report was written was also in remission. One ALPS patient required the addition of mycophenolate mofetil due to prednisolone resistance. The WAS patient was treatment resistant and died due to septicemia. CONCLUSION: Primary AIHA in pediatric patients generally has an acute onset and good response to corticosteroids. Primary or secondary ES has a chronic or relapsing course, and treatment may require other immunosuppressive agents in addition to corticosteroids. Complications of splenectomy must not be underestimated in patients with underlying immunodeficiency. AIHA often causes considerable morbidity and mortality in WAS.

Seroprevalence of hepatitis and human immuno-deficiency virus in multitransfused patients from a pediatric hematology clinic.

OBJECTIVE: Transfusion transmitted hepatitis has been a severe problem in Turkey in pediatric cancer patients and in chronic congenital anemia. The aim of the present study was to investigate the prevalence of hepatitis B, hepatitis C and human immunodeficiency virus infections in these patients in a University Hospital. METHODS: Multi-transfused 66 children (59 acute leukemia, 6 thalassemia major, 1 severe hereditary spherocytosis) diagnosed and followed-up between May, 2000 and December, 2006 were evaluated. Screening of all the patients for HbsAg, anti-HBs, anti-HBc, anti-HCV and anti-HIV was performed at presentation and during the last follow-up. Serologic studies of leukemic patients were also repeated at the end of the chemotherapy. Hepatitis B vaccination was administered to unvaccinated patients with anemia. All blood products were provided by Blood Bank of the Center. RESULTS: No patient was found HBsAg, anti-HCV or anti-HIV positive at diagnosis and at the end of the therapy. There was history of hepatitis B vaccination in only 42% of the patients at diagnosis due to administration of this vaccine to newborns since 1998. At the beginning of the study, 45 % (n=27) of the leukemic patients were immune for hepatitis B, but after completion of the intensive chemotherapy seropositivity persisted in only 28.8 % (n=17). CONCLUSION: Transmission of these viruses is no longer a real problem even in multitransfused immunosuppressed children in Pediatric Hematology Units as a result of the improvements in screening of voluntary blood donors, administration of disposable material in clinics and vaccination by hepatitis B.