A B S T R A C T Hemorrhagic cystitis (HC) is a common and important complication of allogeneic hematopoietic cell transplantation (HCT). Reactivation of BK virus is its most common cause. The more intense immunosuppressive regimens administered to recipients of grafts from alternative donors have been reported to account for the increased susceptibility to HC in this population. This study compares patients undergoing HCT with either a haploidentical donor or a matched related donor, all of whom received identical immunosuppression with a post-transplantation cyclophosphamide-based regimen. The incidence of HC was significantly higher in the patients receiving a haploidentical graft (P = .01). The higher incidence of HC in haploidentical graft recipients is therefore directly related to the inherent immune deficiency that follows HLA-mismatched transplantation, independent of the intensity of pharmacologic immunosuppression. This finding carries significant clinical impact for the prevention and treatment of HC in haploidentical graft recipients.

Hereditary hemochromatosis (HH) is a common autosomal-recessive disorder associated with pathogenic HFE variants, most commonly those resulting in p.Cys282Tyr and p.His63Asp. Recommendations on returning incidental findings of HFE variants in individuals undergoing genome-scale sequencing should be informed by penetrance estimates of HH in unselected samples. We used the eMERGE Network, a multicenter cohort with genotype data linked to electronic medical records, to estimate the diagnostic rate and clinical penetrance of HH in 98 individuals homozygous for the variant coding for HFE p.Cys282Tyr and 397 compound heterozygotes with variants resulting in p.[His63Asp];[Cys282Tyr]. The diagnostic rate of HH in males was 24.4% for p.Cys282Tyr homozygotes and 3.5% for compound heterozygotes (p < 0.001); in females, it was 14.0% for p.Cys282Tyr homozygotes and 2.3% for compound heterozygotes (p < 0.001). Only males showed differences across genotypes in transferrin saturation levels (100% of homozygotes versus 37.5% of compound heterozygotes with transferrin saturation > 50%; p = 0.003), serum ferritin levels (77.8% versus 33.3% with serum ferritin > 300 ng/ml; p = 0.006), and diabetes (44.7% versus 28.0%; p = 0.03). No differences were found in the prevalence of heart disease, arthritis, or liver disease, except for the rate of liver biopsy (10.9% versus 1.8% [p = 0.013] in males; 9.1% versus 2% [p = 0.035] in females). Given the higher rate of HH diagnosis than in prior studies, the high penetrance of iron overload, and the frequency of at-risk genotypes, in addition to other suggested actionable adult-onset genetic conditions, opportunistic screening should be considered for p.[Cys282Tyr];[Cys282Tyr] individuals with existing genomic data.

With proven single-agent activity and favorable toxicity profile of MEK-1/2 inhibition in advanced leukemia, investigation into combination strategies to overcome proposed resistance pathways is warranted. Resistance to MEK inhibition is secondary to upstream hyperactivation of RAS/RAF or activation of the PI3K/PTEN/AKT/mTOR pathway.

To estimate the incidence of Lyme borreliosis in France, describe its clinical presentations, and assess its potential risk factors, we conducted a nationwide prospective study in the French Sentinelles Network, consisting of 1178 general practitioners (GPs). Of these, 875 (74%), i.e. 1.6% of all French GPs, participated in the study from May 1999 to April 2000. Eighty-six cases of Lyme disease were reported and validated, of which 77 (90%) consisted of erythema migrans. At national level, the incidence was estimated at 9.4/100,000 inhabitants. Compared to the French general population, Lyme disease patients were older (P<10(-4)), more were living in rural areas (P<10(-3)), and amongst the working population, more were farmers (P<10(-3)) and fewer, salaried workers (P<0.005). Cervidae density correlated strongly with the estimated regional incidence of Lyme disease (r=0.82). Both incidence data and identified risk factors can help to target measures for its prevention and treatment.