[Hemoglobin sickle cell disease: experience of the Yalgado Ouedraogo University Hospital of Ouagadougou, Burkina Faso]. / Le syndrome drépanocytaire de type hémoglobine SC : expérience du CHU Yalgado Ouédraogo de Ouagadougou (Burkina Faso).

OBJECTIVES: To evaluate the clinical features of children with hemoglobin sickle cell disease (HbSC) and compare them to children with sickle cell anemia (HbSS). POPULATION AND METHODS: This was a descriptive and retrospective study. New patients with sickle cell disease who consulted at the Yalgado Ouédraogo University Hospital's Pediatric Center in Ouagadougou, Burkina Faso, between May 2005 and June 2006, were included. They were free of any major disease unrelated to sickle cell disease. Clinical and laboratory results reported for these children were based on their health book and medical records. RESULTS: Sixty-one children were included in the study, 38 and 23 children were positive for HbSC and HbSS, respectively; there was no significant difference between the 2 groups in terms of sex ratio or mean age at inclusion. Mean age at diagnosis was 5 years and 2 years for HbSC and HbSS children, respectively. The first clinical event appeared at a significantly later age for HbSC than HbSS children (4 years versus 2 years). Painful episodes were equivalent in mean number per year and mean length per episode between the 2 groups; the median hemoglobin (Hb) level at inclusion was significantly higher for HbSC than for HbSS children, i.e., 95 g/l versus 70 g/l. CONCLUSION: At the Yalgado Ouédraogo University Hospital Pediatric Center, children with HbSC disease presented clinical and biological features very similar to those with HbSS.

[Vaccination status of children with sickle cell disease in Ouagadougou (Burkina Faso)]. / Evaluation du statut vaccinal de l'enfant drépanocytaire de la ville de Ouagadougou (Burkina Faso).

Because of the importance of preventive activities in fighting sickle cell disease, we sought to assess the vaccination status of children with this disease in Burkina-Faso. This cross-sectional study used a questionnaire to collect information from outpatients of the pediatric department of the Yalgado Ouédraogo hospital center and of Saint Camille medical center, also in Ouagadougou, from October 2005 through March 2006. The study included 122 children, 52.5% of whom had an SC phenotype. Coverage for vaccinations included in the WHO expanded vaccination programme was 97.5%. For other specific vaccines, coverage varied from 5.7% for the anti-Haemophilus influenzae vaccine to 65.8% for the 23 pneumococci included in pneumo23. The major reasons for non-vaccination were ignorance and the prohibitive cost of these vaccines for the families who knew about them. These results suggest the need for a national program against sickle cell disease, which should enable treatment centers to include in their preventive activities a specific vaccination program. Only in this way can we reduce the mortality rates among those younger than 5 years by 40% by 2015, the goal of the International Organization against sickle cell disease, to which Burkina-Faso belongs.

Evaluation of the versatile character of a nanoemulsion formulation.

The formulate-ability of six model active pharmaceutical ingredients (API), with different physico-chemical profiles, in a nanoemulsion designed to be intraveinously administrable was explored. Nanoemulsions were spontaneously generated at room temperature by pouring a phosphate buffer in an anhydrous mixture containing pharmaceutically acceptable triglycerides and non-ionic surfactants. After determination of the apparent solubility of each API in excipients and characterization of mixtures by DSC, API-loaded nanoemulsions were formulated and characterized in terms of granulometric properties, surface potential, drug recovery efficiency, pH, osmolarity, in vitro drug release, and stability. Except ciprofloxacin, a BCS class IV drug, all studied APIs were soluble in at least one excipient used, i.e. Labrasol. At 2 wt% API, all drug-loaded nanoemulsions present properties compatible with i.v. administration. The formulation should permit to increase apparent solubility of poorly water-soluble APIs, and also to prolong delivery of hydrophobic as well of more hydrophilic compounds. Herein, the relative affinity of the API for nanodroplets and the release medium would directly influence drug release profiles. Nanoemulsions were stable for 7 days. They could also been extemporaneously reconstituted before use. Such a versatile nanoemulsion would provide a valuable option as formulation strategy for improvement of drug properties.

Accelerated ketoprofen release from polymeric matrices: importance of the homogeneity/heterogeneity of excipient distribution.

Polymeric matrices loaded with 10-50% ketoprofen were prepared by hot-melt extrusion or spray-drying. Eudragit E, PVP, PVPVA and HPMC were studied as matrix formers. Binary "drug-Eudragit E" as well as ternary "drug-Eudragit E-PVP", "drug-Eudragit E-PVPVA" and "drug-Eudragit E-HPMC" combinations were investigated and characterized by optical macro/microscopy, SEM, particle size measurements, mDSC, X-ray diffraction and in vitro drug release studies in 0.1 M HCl. In all cases ketoprofen release was much faster compared to a commercially available product and the dissolution of the drug powder (as received). Super-saturated solutions were obtained, which were stable during at least 2 h. Importantly, not only the composition of the systems, but also their inner structure potentially significantly affected the resulting ketoprofen release kinetics: For instance, spray-drying ternary ketoprofen:Eudragit E:HPMC combinations led to a more homogenous HPMC distribution within the systems than hot-melt extrusion, as revealed by mDSC and X-ray diffraction. This more homogenous HPMC distribution resulted in more pronounced hindrance for water and drug diffusion and, thus, slower drug release from spray-dried powder compared to hot-melt extrudates of identical composition. This "homogeneity/heterogeneity effect" even overcompensated the "system size effect": the surface exposed to the release medium was much larger in the case of the spray-dried powder. All formulations were stable during storage at ambient conditions in open vials.