Selective luteinizing hormone deficiency due to mutations in the luteinizing hormone beta-subunit gene (LHB) is a rare cause of hypogonadism. We describe the clinical features of a consanguineous family in which three siblings, two men and one woman, had hypogonadism related to isolated luteinizing hormone deficiency. These subjects have a newly discovered homozygous mutation of a 5' splice site in LHB: IVS2+1G-->C. This mutation disrupts the splicing of messenger RNA (mRNA), generating a gross abnormality in the processing of the luteinizing hormone beta-subunit mRNA, which abrogates the secretion of luteinizing hormone. We also determined that the female phenotype of this LHB mutation is characterized by normal pubertal development, secondary amenorrhea, and infertility.

In the past decade, a new class of hemodialysis (HD) membranes (high retention onset class) became available for clinical use. The high cutoff (HCO) and the medium cutoff (MCO) membranes have wider pores and more uniformity in pore size, allowing an increased clearance of uremic toxins. Owing to the mechanism of backfiltration/internal filtration, middle molecules are dragged by the convective forces, and no substitution solution is needed. The HCO dialyzer is applied in septic patients with acute kidney injury requiring continuous kidney replacement therapy. The immune response is modulated thanks to the removal of inflammatory mediators. Another current application for the HCO dialyzer is in hematology, for patients on HD secondary to myeloma-kidney, since free light chains are more efficiently removed with the HCO membrane, reducing their deleterious effect on the renal tubules. In its turn, the MCO dialyzer is used for maintenance HD patients. A myriad of clinical trials published in the last three years consistently demonstrates the ability of this membrane to remove uremic toxins more efficiently than the high-flux membrane, an evolutionary disruption in the HD standard of care. Safety concerns regarding albumin loss as well as blood contamination from pyrogens in the dialysate have been overcome. In this update article, we explore the rise of new dialysis membranes in the light of the scientific evidence that supports their use in clinical practice.

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Background: Identifying patients with hepatitis C virus (HCV) infection and enhancing the cascade of care are essential for eliminating HCV infection. This study aimed to estimate the prevalence of positive anti-HCV serology in Brasilia, Brazil, and evaluate the efficiency of the cascade of care for HCV-positive individuals.Methods: This cross-sectional study analyzed 57,697 rapid screening tests for hepatitis C in individuals aged > 40 years between June 2018 and June 2019. HCV-positive patients were contacted and scheduled to undergo the HCV RNA viral test, genotyping, and transient elastography.Results: The prevalence of positive serology was 0.27%. Among 161 patients with positive anti-HCV serology, 124 (77%) were contacted, 109 (67.7%) were tested for HCV RNA viral load, and 69 (42.8%) had positive results. Genotype 1 (75%) was the most prevalent genotype. Among 65 patients (94.2%) who underwent transient elastography, 30 (46.2%) presented with advanced fibrosis. Additionally, of the 161 patients, 55 (34.1%) were referred for treatment, but only 39 (24.2%) complied, with 36 (22.4%) showing sustained virological response. By the end of the study, 16 patients were still awaiting to receive medication. Conclusions:The prevalence of HCV-positive patients was low in Brasilia, and the gaps in the cascade of care for these patients were significantly below the targets of HCV infection elimination. This study opens new avenues for eliminating HCV infection and suggests that partnerships with clinical laboratories to conduct anti-HCV tests are a useful strategy to improve HCV diagnosis.

Disruptive technologies for hemodialysis: medium and high cutoff membranes. Is the future now?Tecnologias disruptivas para hemodiálise: membranas de ponto de corte médio e alto. O futuro é agora?