Abels, Elizabeth A

AbstractBackgroundHemolytic disease of the fetus and newborn (HDFN) is caused by maternal alloantibody‐mediated destruction of fetal/neonatal red blood cells (RBCs). While the pathophysiology has been well‐characterized, the clinical and laboratory monitoring practices are inconsistent.MethodsWe surveyed 103 US institutions to characterize laboratory testing practices for individuals with fetuses at risk of HDFN. Questions included antibody testing and titration methodologies, the use of critical titers, paternal and cell‐free fetal DNA testing, and result reporting and documentation practices.ResultsThe response rate was 44% (45/103). Most respondents (96%, 43/45) assess maternal antibody titers, primarily using conventional tube‐based methods only (79%, 34/43). Among respondents, 51% (23/45) rescreen all individuals for antibodies in the third trimester, and 60% (27/45) perform paternal RBC antigen testing. A minority (27%, 12/45) utilize cell‐free fetal DNA (cffDNA) testing to predict fetal antigen status. Maternal antibody titers are performed even when the fetus is not considered to be at risk of HDFN based on cffDNA or paternal RBC antigen testing at 23% (10/43) of sites that assess titers.DiscussionThere is heterogeneity across US institutions regarding the testing, monitoring, and reporting practices for pregnant individuals with fetuses at risk of HDFN, including the use of antibody titers in screening and monitoring programs, the use of paternal RBC antigen testing and cffDNA, and documentation of fetal antigen results. Standardization of laboratory testing protocols and closer collaboration between the blood bank and transfusion medicine service and the obstetric/maternal‐fetal medicine service are needed.

Abstract Anti‐glomerular basement membrane (anti‐GBM) disease (formerly known as Goodpasture's syndrome) is a rare autoinflammatory condition that affects the renal and/or pulmonary capillaries. The standard therapeutic regimen for anti‐GBM disease involves therapeutic plasma exchange (TPE), cyclophosphamide, and corticosteroids to rapidly remove and inhibit autoantibody production and reduce organ inflammation. Herein we report an 82‐year‐old female who developed anti‐GBM disease but expired despite therapy, secondary to multi‐organ failure in the setting of disseminated adenovirus disease. We discuss the utility and potential adverse effect of daily TPE for a protracted course (ie, 10‐14 days), the recommended TPE intensity in the 2023 American Society for Apheresis guidelines, updated from every‐other‐day TPE in the 2019 guidelines, despite no new data. We also highlight the potential for unusual infections to occur in these patients due to the profound immunosuppression, and discuss the importance of balancing immunosuppression to treat the disease with close surveillance of any potential opportunistic infections.