Survival among children and adults with sickle cell disease in Belgium: Benefit from hydroxyurea treatment.

OBJECTIVE: To evaluate the survival of patients with sickle cell disease (SCD) recorded in the Belgian SCD Registry and to assess the impact of disease-modifying treatments (DMT). METHOD: The Registry created in 2008 included patients of eight centers. All available data in 2008 were retrospectively encoded in the database. After 2008 and until 2012, all data were recorded prospectively for already registered patients as well as newly diagnosed subjects. Data were registered from neonatal screening or from diagnosis (first contact) until last follow-up or death. Data included diagnosis, demography, and outcome data. RESULTS: We collected data from 469 patients over a 5,110 patient years (PY) follow-up period. The global mortality rate was low (0.25/100 PY), although 13 patients died (2.8%) and was similar between children, adolescents (10-18 years), and young adults (P = 0.76). Out of the cohort, 185 patients received hydroxyurea at last follow-up (median duration of treatment: 10.3 years), 90 underwent hematopoietic stem cell transplantation (HSCT), 24 were chronically transfused, and 170 had never had any DMT. Hydroxyurea showed significant benefit on patients outcome as reflected by a lower mortality rate compared to transplanted individuals or people without DMT (0.14, 0.36, and 0.38 per 100 PY, respectively) and by higher Kaplan-Meier estimates of 15 year survival (99.4%) compared to HSCT (93.8%; P = 0.01) or no DMT groups (95.4%; P = 0.04). CONCLUSION: SCD mortality in Belgium is low with no increase observed in young adults. Patients treated with hydroxyurea demonstrate a significant benefit in survival when compared to those without DMT or transplanted.

Imported Malaria in Children: A Study Over an 11-Year Period in Brussels.

BACKGROUND: Malaria is a major global public health concern in endemic countries and imported childhood malaria is increasing in malaria non-endemic countries. METHODS: This was a retrospective case review of all laboratory-confirmed malaria cases in children 0-16 years admitted between 2009 and 2019 in 2 large university teaching Hospitals in Brussels. RESULTS: A total of 160 children with a median age of 6.8 years (range 5-191 months) were included. We identified 109 (68%) children living in Belgium who had acquired malaria during their visit to malaria-endemic countries to visiting friends and relatives (VFRs), 49 children (31%) visitors or newly installed migrants, and 2 Belgian tourists. Peak seasonal incidence occurred between August and September. Plasmodium falciparum was responsible for 89% of all malaria cases. Almost 80% of children living in Belgium visited a travel clinic for advice, but only one-third reported having taken the prophylaxis schedule according to the recommendations. Based on WHO criteria, 31 children (19.3%) developed severe malaria; most of the patients with severe malaria were VFR travelers and were significantly younger, had higher leukocytosis, had more thrombocytopenia, higher CRP, and lower natremia compared with patients with an uncomplicated course. All children recovered fully. CONCLUSIONS: Malaria is a significant cause of morbidity among returning travelers and newly arrived immigrants to Belgium. Most of the children had an uncomplicated disease course. Physicians should educate families about traveling to malaria-endemic areas to correct malaria preventive measures and prophylaxis.

Invasive Bacterial Infections in Children With Sickle Cell Disease: 2014-2019.

BACKGROUND: Children with sickle cell disease (SCD) are at a high risk of invasive bacterial infections (IBI). Universal penicillin prophylaxis and vaccination, especially against Streptococcus pneumoniae, have deeply changed its epidemiology. Analysis of IBI in children with SCD in a post-13-valent pneumococcal vaccine era is limited. METHODS: Twenty-eight pediatric hospitals from 5 European countries retrospectively collected IBI episodes in SCD children aged 1 month to 18 years between 2014 and 2019. IBI was defined as a positive bacterial culture or polymerase chain reaction from a normally sterile fluid: blood, cerebrospinal, joint, or pleural fluid and deep surgical specimen. RESULTS: We recorded 169 IBI episodes. Salmonella spp. was the main isolated bacteria (n = 44, 26%), followed by Streptococcus pneumonia (Sp; n = 31, 18%) and Staphylococcus aureus (n = 20, 12%). Salmonella prevailed in osteoarticular infections and in primary bacteremia (45% and 23% of episodes, respectively) and Sp in meningitis and acute chest syndrome (88% and 50%, respectively). All Sp IBI occurred in children ≤10 years old, including 35% in children 5 to 10 years old. Twenty-seven (17%) children had complications of infection and 3 died: 2 because of Sp, and 1 because of Salmonella. The main risk factors for a severe IBI were a previous IBI and pneumococcal infection (17 Sp/51 cases). CONCLUSIONS: In a post-13-valent pneumococcal vaccine era, Salmonella was the leading cause of bacteremia in IBI in children with SCD in Europe. Sp came second, was isolated in children ≤10 years old, and was more likely to cause severe and fatal cases.

An estimation of the incidence and demographic picture of the major hemoglobinopathies in Belgium (from a confidential inquiry).

An estimation of the incidence and demographic picture of the major hemoglobinopathies in Belgium has been approached through a confidential inquiry sent to 228 pediatric and adult hematological departments. Forty-two percent of responses showed that 417 patients are known in Belgium: 83% with sickle cell disease, 13% with beta-thalassemia (beta-thal) major, 2% with beta-thal intermedia, and 1% with Hb H disease. Twenty-five percent of the sickle cell disease patients and 54% of those suffering from a beta-thal major were older than 20 years. Three hospitals ensure the follow-up of 70% of the patients and are situated in Brussels, Belgium; a follow-up of less than 20 patients was reported at 21 centers. These results confirm that sickle cell disease is the major hemoglobinopathy in Belgium; it concerns mostly pediatricians but adult hematologists are also confronted with these pathologies. Therefore, it is necessary to implement integrated programs of prevention and treatment.

Neonatal screening improves sickle cell disease clinical outcome in Belgium.

Objectives To compare the outcomes of sickle cell disease patients diagnosed through neonatal screening with those who were not. Methods In an observational multicenter study in Belgium, 167 screened and 93 unscreened sickle cell disease patients were analyzed for a total of 1116 and 958 patient-years of follow-up, respectively. Both groups were compared with propensity score analysis, with patients matched on three covariates (gender, genotype, and central Africa origin). Bonferroni correction was applied for all comparisons. Results Kaplan-Meier estimates of survival without bacteremia were significantly higher in the screened group than the unscreened group (94.47%; [95% CI, 88.64-97.36%] versus 83.78% [95% CI, 72.27-90.42%]), p = 0.032. Non-significant differences between both groups were reported for survival without acute chest syndrome, acute anemia, cerebral complication, severe infection, and vaso-occlusive crisis. Significantly lower hospitalization rate and days per 100 patient-years were observed in the screened compared with the unscreened group (0.27 vs. 0.63 and 1.25 vs. 2.82, p = 0.0006 and <0.0001). Conclusion These data confirm the benefit of a neonatal screening programme in reducing bacteremia and hospitalization.