Next‐generation sequencing for the diagnosis of MYH9‐RD: Predicting pathogenic variants

The heterogeneous manifestations of MYH9‐related disorder (MYH9‐RD), characterized by macrothrombocytopenia, Döhle‐like inclusion bodies in leukocytes, bleeding of variable severity with, in some cases, ear, eye, kidney, and liver involvement, make the diagnosis for these patients still challenging in clinical practice. We collected phenotypic data and analyzed the genetic variants in more than 3,000 patients with a bleeding or platelet disorder. Patients were enrolled in the BRIDGE‐BPD and ThromboGenomics Projects and their samples processed by high throughput sequencing (HTS). We identified 50 patients with a rare variant in MYH9. All patients had macrothrombocytes and all except two had thrombocytopenia. Some degree of bleeding diathesis was reported in 41 of the 50 patients. Eleven patients presented hearing impairment, three renal failure and two elevated liver enzymes. Among the 28 rare variants identified in MYH9, 12 were novel. HTS was instrumental in diagnosing 23 patients (46%). Our results confirm the clinical heterogeneity of MYH9‐RD and show that, in the presence of an unclassified platelet disorder with macrothrombocytes, MYH9‐RD should always be considered. A HTS‐based strategy is a reliable method to reach a conclusive diagnosis of MYH9‐RD in clinical practice.     

A Murine Model of Chronic Lymphocytic Leukemia Based on B Cell-Restricted Expression of Sf3b1 Mutation and Atm Deletion

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Schistosomiasis and infection with human immunodeficiency virus 1 in rural Zimbabwe: systemic inflammation during co-infection and after treatment for schistosomiasis

We previously reported that treatment for schistosomiasis in persons infected with human immunodeficiency virus 1 (HIV-1) attenuated HIV replication as measured by plasma HIV RNA. We investigated systemic inflammation as measured by plasma levels of soluble tumor necrosis factor-alpha receptor II (sTNF-rII), interleukin-8, (IL-8), and IL-10 during schistosomiasis and HIV co-infection and after schistosomiasis treatment. The cohort was composed of 378 persons who were or were not infected with HIV-1, Schistosoma haematobium, or S. mansoni. Schistosomiasis-infected persons were randomized to receive praziquantel (40 mg/kg) at baseline or at the three-month follow-up. sTNF-rII and IL-8 were positively associated with schistosomiasis intensity as measured by circulating anodic antigen (CAA), regardless of HIV status. Interleukin-10 was positively associated with CAA in HIV-negative participants. IL-8 levels were higher in S. mansoni-infected individuals. Treatment for schistosomiasis caused a decrease in levels of sTNF-rII (P < 0.05) and IL-10 (P < 0.001). Our results indicate that schistosomiasis treatment may attenuate HIV replication by decreasing systemic inflammation.     

Schistosomiasis and HIV-1 infection in rural Zimbabwe: effect of treatment of schistosomiasis on CD4 cell count and plasma HIV-1 RNA load

To determine whether treatment of schistosomiasis has an effect on the course of human immunodeficiency virus type 1 (HIV-1) infection, individuals with schistosomiasis and with or without HIV-1 infection were randomized to receive praziquantel treatment at inclusion or after a delay of 3 months; 287 participants were included in the study, and 227 (79%) were followed up. Among the 130 participants who were coinfected, those who received early treatment (n=64) had a significantly lower increase in plasma HIV-1 RNA load than did those who received delayed treatment (n=66) (P<.05); this difference was associated with no change in plasma HIV-1 RNA load in the early intervention group (P=.99) and an increase in plasma HIV-1 RNA load in the delayed intervention group (P<.01). Among the 227 participants who were followed up, those who received early treatment (n=105) had an increase in CD4 cell count, whereas those who received delayed treatment (n=122) did not (P<.05); this effect did not differ between participants when stratified by HIV-1 infection status (P=.17). The present study suggests that treatment of schistosomiasis can reduce the rate of viral replication and increase CD4 cell count in the coinfected host.     

Schistosomiasis and HIV-1 infection in rural Zimbabwe: implications of coinfection for excretion of eggs

BACKGROUND: Stunted development and reduced fecundity of Schistosoma parasites in immunodeficient mice and the impaired ability of human immunodeficiency virus 1 (HIV-1)-infected humans to excrete schistosome eggs have been described. This study explores the effect that HIV-1-associated immunodeficiency has on the excretion of schistosome eggs in a large cohort of coinfected individuals. METHODS: In a cross-sectional survey, urine and stool samples were obtained from and HIV-1 status was determined for 1545 individuals. More extensive data, including quantitative measures of intensity of infection in schistosomiasis and immunodeficiency, were collected in the Mupfure schistosomiasis and HIV longitudinal cohort, composed of 379 participants of whom 154 were coinfected with HIV-1 and Schistosoma parasites. RESULTS: In the cross-sectional survey, the overall prevalence of schistosomiasis was 43.4%, and 26.3% of the participants were infected with HIV-1. Schistosome infections were due to Schistosoma haematobium in 63.6% of cases, S. mansoni in 18.1% of cases, and dual infections in 18.4% of cases. Intensities of Schistosoma infections, measured by the number of eggs excreted and by the level of circulating anodic antigens, did not differ between HIV-1-negative and HIV-1-positive participants coinfected with S. haematobium, S. mansoni, or both. CD4 cell counts were significantly lower in HIV-1-positive participants and in S. mansoni-infected HIV-1-negative participants than in other participants. CONCLUSION: The present study suggests that adult HIV-1-related immunodeficiency does not impair the ability to excrete eggs in low-intensity infection with S. haematobium, S. mansoni, or both and that infection with HIV-1 may not have major implications for diagnosis and surveillance of schistosomiasis.     

Reduced mortality and CD4 cell loss among carriers of the interleukin-10 -1082G allele in a Zimbabwean cohort of HIV-1-infected adults

OBJECTIVES: To evaluate the effect on HIV progression of single nucleotide polymorphisms in promoters of the genes for tumour necrosis factor (TNF)-alpha and interleukin (IL)-10 and known to influence cytokine production. METHODS: Survival was documented for 4.3 years after baseline for 198 HIV-1-infected and 180 HIV-uninfected individuals from the Mupfure Schistosomiasis and HIV Cohort in rural Zimbabwe. Polymorphisms determined were -592C>A and -1082A>G for IL-10 and -238G>A and -308G>A for TNF-alpha. CD4 cell counts, plasma HIV RNA, soluble TNF receptor II (sTNF-rII), IL-8 and IL-10 were also measured. RESULTS: Mortality was lower in carriers of the IL-10 -1082G high-producer allele (hazard ratio, 0.47; P < 0.01). CD4 cell count decrease in participants reporting for the follow-up at 3 years was attenuated in carriers of this allele (P < 0.01). In univariate analysis, plasma IL-10, IL-8, and sTNF-rII correlated negatively with CD4 cell count, positively with HIV RNA, and higher levels predicted mortality. In multivariate analysis only sTNF-rII was an independent predictor of HIV progression markers and mortality. Indeed, sTNF-rII predicted mortality (P < 0.01) at a level of significance comparable to HIV RNA (P < 0.01) and CD4 cell count (P < 0.05). CONCLUSIONS: In carriers of IL-10 -1082G, an allele linked to increased IL-10 production, survival was doubled and CD4 cell decrease was attenuated compared with noncarriers. Only sTNF-rII and not plasma IL-10 was an independent predictor of HIV progression markers and mortality. This study supports immune activation as a driving force in HIV pathogenesis and indicates a protective role of IL-10 -1082G that should be evaluated in other cohorts.     

Coping with Drought in Rural Papua New Guinea: A Western Highlands Case Study

The short- and long-term effects of climate change on Papua New Guinea’s agricultural sector have generated significant debate in recent times. Current literature demonstrates that different population groups have differing levels of vulnerability and resilience to the flow-on effects of climate change, particularly drought. Yet different schools of thought on the country’s food security and effects on livelihoods persist. This article draws on evidence from research conducted in the Western Highlands of Papua New Guinea as part of a bigger economic empowerment project to illustrate the vulnerabilities of one community of rural semisubsistence farmers to drought-induced food insecurity. It examines responses to drought, identifies modes of resilience, and discusses the implications for future actions.