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Three children with sickle cell disease developed acute chest syndrome that was found to be caused by plastic bronchitis. Plastic bronchitis is characterized by the formation of thick mucus that lines the bronchial tubes and hardens, forming a cast. The children did not respond to drugs normally used to clear chest secretions. Bronchoscopy revealed the presence of a substance lining the bronchial tubes that resembled rubber. A bronchoscope was also used to remove the casts and microscopic examination of the material revealed it to be fibromucinous material with some inflammatory cells., Plastic bronchitis is reported as a rare entity characterized by the formation of branching mucoid bronchial casts.[1,2] These endobronchial casts of rubber-like consistency are organized aggregates of mucofibrinous substrate mixed [...]

Abstract The influence of host genetics on susceptibility to Plasmodium falciparum malaria has been extensively studied over the past twenty years. It is now clear that malaria parasites have imposed strong selective forces on the human genome in endemic regions. Different genes have been identified that are associated with different malaria related phenotypes. Factors that promote severity of malaria include parasitaemia, parasite induced inflammation, anaemia and sequestration of parasitized erythrocytes in brain microvasculature. Recent advances in human genome research technologies such as genome-wide association studies (GWAS) and fine genotyping tools have enabled the discovery of several genetic polymorphisms and biomarkers that warrant further study in host-parasite interactions. This review describes and discusses human gene polymorphisms identified thus far that have been shown to be associated with susceptibility or resistance to P. falciparum malaria. Although some polymorphisms play significant roles in susceptibility to malaria, several findings are inconclusive and contradictory and must be considered with caution. The discovery of genetic markers associated with different malaria phenotypes will help elucidate the pathophysiology of malaria and enable development of interventions or cures. Diversity in human populations as well as environmental effects can influence the clinical heterogeneity of malaria, thus warranting further investigations with a goal of developing new interventions, therapies and better management against malaria.

Over 15 years, 14 patients with yersiniosis in two North American comprehensive thalassemia clinics (0.6 cases per 100 patient-years) presented with fever (100%), diarrhea (86%), right-lower-quadrant abdominal pain (71%), bacteremia (57%), a palpable abdominal mass (36%), and pharyngitis (28%). Clinically apparent infection occurred within 10 days of blood transfusion in 57% of patients. Nine patients (64%) had only a modest elevation in serum level of ferritin (<2,000 µg/L). Patients with focal abdominal findings had a higher body iron burden, as estimated by the serum ferritin level, and significant intraabdominal suppurative complications. Two patients were not receiving iron-chelating therapy with deferoxamine; one patient was receiving the experimental chelator deferiprone (L1). Iron-loaded patients with β-thalassemia are at greatly increased risk for severe yersiniosis, even when their body iron burden (as indicated by the serum ferritin level) is only moderately elevated and they are not receiving iron-chelating therapy with deferoxamine. [ABSTRACT FROM PUBLISHER]

Purpose: Our objective was to compare observed and expected genotype proportions from newborn screening surveys of structural hemoglobin variants., Methods: We conducted a systematic review of newborn screening surveys of hemoglobins S and C in Africa and the Middle East. We compared observed frequencies to those expected assuming Hardy-Weinberg equilibrium (HWE). Significant deviations were identified by an exact test. The fixation index FIS was calculated to assess excess homozygosity. We compared newborn estimates corrected and uncorrected for HWE deviations using demographic data., Results: Sixty samples reported genotype counts for hemoglobin variants in Africa and the Middle East. Observed and expected counts matched in 27%. The observed number of sickle cell anemia (SCA) individuals was higher than expected in 42 samples, reaching significance (P < 0.05) in 24. High FIS values were common across the study regions. The estimated total number of newborns with SCA, corrected based on FIS, was 33,261 annual births instead of 24,958 for the 38 samples across sub-Saharan Africa and 1,109 annual births instead of 578 for 12 samples from the Middle East., Conclusion: Differences between observed and expected genotype frequencies are common in surveys of hemoglobin variants in the study regions. Further research is required to identify and quantify factors responsible for such deviations. Estimates based on HWE might substantially underestimate the annual number of SCA-affected newborns (up to one-third in sub-Saharan Africa and one-half in the Middle East).

The influence of host genetics on susceptibility to Plasmodium falciparum malaria has been extensively studied over the past twenty years. It is now clear that malaria parasites have imposed strong selective forces on the human genome in endemic regions. Different genes have been identified that are associated with different malaria related phenotypes. Factors that promote severity of malaria include parasitaemia, parasite induced inflammation, anaemia and sequestration of parasitized erythrocytes in brain microvasculature.Recent advances in human genome research technologies such as genome-wide association studies (GWAS) and fine genotyping tools have enabled the discovery of several genetic polymorphisms and biomarkers that warrant further study in host-parasite interactions. This review describes and discusses human gene polymorphisms identified thus far that have been shown to be associated with susceptibility or resistance to P. falciparum malaria. Although some polymorphisms play significant roles in susceptibility to malaria, several findings are inconclusive and contradictory and must be considered with caution. The discovery of genetic markers associated with different malaria phenotypes will help elucidate the pathophysiology of malaria and enable development of interventions or cures. Diversity in human populations as well as environmental effects can influence the clinical heterogeneity of malaria, thus warranting further investigations with a goal of developing new interventions, therapies and better management against malaria.

This study examined the theoretical availability of compatible unrelated umbilical cord blood (UCB) units for hematopoietic stem cell transplantation (HSCT) of children with sickle cell disease (SCD), matched for DRB1 at high resolution. UCB units registered via Bone Marrow Donors Worldwide were matched with patients who had been previously typed for possible HSCT. Suitable matching was determined after typing at antigen level at A and B loci and allele-level typing at DRB1. Forty patients met criteria for analysis. All matched at four of six loci with at least two UCB units, and 50% (n = 20) matched at five of six loci with at least one unit. In patients matched at four loci or more, significantly more units per patient (median 19 vs. 2 units; P = 0.03) at higher cell dose (median 205 vs. 113 best nucleated cell dose per unit; P < 0.01) were identified compared with patients matched at five loci or more. Hypothetically, at a dose of at least 5 x 10 nucleated cells/kg, 54% of patients weighing 40 kg would match with units at four or more of six loci and 5% at five or more of six loci. This study suggests that cord blood units matching at four or more of six HLA loci at acceptable cell doses can be identified for a majority of children with SCD weighing 40 kg or less. Availability of units matched at five or more of six HLA loci was more limited. Defining procedure-related risks and benefits remains a challenge.