Pregnancy in Classical Paroxysmal Nocturnal Hemoglobinuria and Aplastic Anemia-Paroxysmal Nocturnal Hemoglobinuria: A High-Risk Constellation.

Pregnancies in paroxysmal nocturnal hemoglobinuria (PNH) are associated with increased morbidity and mortality. Retrospective studies suggest that outcome has improved with the advent of the complement inhibitor eculizumab. To substantiate this assumption we analyzed the data from patients treated in our department since 2009. All patients were included in the International PNH registry and followed prospectively. We identified 16 pregnancies in 9 patients with classical PNH, and two pregnancies in two patients with aplastic anemia (AA)-PNH. In classical PNH, 13 pregnancies were supported by eculizumab. Breakthrough hemolysis occurred in six pregnancies, necessitating an increase in the biweekly eculizumab dose from 900 mg to 1,200-1,800 mg. Red blood cell transfusions were given in six and platelet transfusions in two pregnancies. A Budd-Chiari syndrome and cholecystitis complicated the course of two pregnancies. Four of 13 pregnancies supported by eculizumab ended in spontaneous abortion or stillbirth, and one was prematurely terminated because of fetal trisomy 21. None of the three pregnancies not supported by eculizumab had a successful outcome. Half the deliveries were preterm. None of the patients died, and, in all but one patient, the post-partum period was uneventful. Both pregnancies in patients with AA-PNH took a favorable course. Our results confirm low maternal mortality and frequent breakthrough hemolysis in pregnant PNH patients receiving eculizumab. Fetal mortality and the rate of preterm delivery were higher than reported previously, possibly related to the use of registry data that are likely to reduce the risk of publication and recall biases.

Veno-Venous Extracorporeal Membrane Oxygenation in Adult Patients with Sickle Cell Disease and Acute Chest Syndrome: a Single-Center Experience.

Acute chest syndrome (ACS) in adult patients with sickle cell disease represents a leading cause of death. It is characterized by a new density on chest X-ray accompanied by fever and/or respiratory symptoms. Currently, 49 adult patients with sickle cell disease are registered at our department. By now, 12 patients (24.5%) suffered from ACS and two patients showed multiple/recurrent (>2) episodes. Death in one patient was related to acute respiratory failure secondary to ACS. In three patients with ACS, invasive mechanical ventilation and subsequent veno-venous extracorporeal membrane oxygenation (VV-ECMO) was mandatory. Veno-venous ECMO was applied within 24 hours upon arrival to the intensive care unit (ICU). All patients were treated aggressively for ACS including exchange transfusions [packed red blood cell (pRBC) units 5-16] maintaining a Hb S threshold of <30.0% in addition to broad-spectrum antibiotics, resulting in a successful outcome following decannulation from VV-ECMO (49 hours, 251 hours, 30 min., and 98 hours, respectively). Limited information is presently available on the use of VV-ECMO in adult patients with sickle cell disease in the context of acute respiratory failure secondary to ACS. The adequate timing of the decision to place ECMO in critically ill adults with sickle cell disease, incapable of being treated by conventional mechanical ventilation secondary to very severe vaso-occlusive crisis (VOC), might further reduce mortality rates while treating the underlying condition.

No evidence for hypogammaglobulinemia in patients with paroxysmal nocturnal hemoglobinuria (PNH) chronically treated with ravulizumab.

INTRODUCTION: Ravulizumab (ALXN1210) is a long-lasting recycling IgG monoclonal antibody with an increased affinity for the neonatal Fc receptor (FcRn). The FcRn is essential for regulating IgG homeostasis. Saturation of the FcRn pathway is seen under high IgG doses as they compete with endogenous IgG to bind the FcRn by their Fc regions, resulting in enhanced IgG clearance. PATIENTS/METHODS: Between Jan 2016 and Jun 2019 (median observation time 21.6 months (6-37.7 months)) serum IgG concentrations and IgG1-4 subclasses were evaluated over a longitudinal course (post-hoc analysis) in 12 ravulizumab-treated adult patients with paroxysmal nocturnal hemoglobinuria (PNH) (58% (7/12) males, median age 50 years (yrs) (18-70 yrs)). All patients were enrolled in one of the three ravulizumab-PNH-related trials (201-, 301-, or 302-study) at the University Hospital Essen. RESULTS: Baseline IgG concentrations were documented in 11 out of the 12 patients prior to ravulizumab treatment (median IgG 9.9 g/L (5-13.5 g/L)). In two female patients a clinically not relevant hypogammaglobulinemia with an associated IgG1 or a combined IgG1/IgG2 deficiency prior to treatment was documented. The data were further stratified with regard to various treatment intervals as multiple analyses were obtained. Throughout observation time IgG concentrations remained within physiologic ranges with no evidence of a treatment-related IgG depletion (median IgG at study endpoint 10.1 g/L (6-13.4 g/L)). CONCLUSION: In ravulizumab-treated PNH patients, IgG and IgG subclass levels which are regulated by the FcRn remained unaffected. Therefore, no treatment associated hypogammaglobulinemia is to be feared under chronic ravulizumab therapy.

Serologic response to meningococcal vaccination in patients with cold agglutinin disease (CAD) in the novel era of complement inhibition.

Cold agglutinin disease (CAD) is a rare, potentially life-threatening acquired autoimmune hemolytic anemia characterized by hemagglutination and hemolysis due to immunoglobulin-mediated (usually IgMκ) classic complement pathway activation. Complement inhibition (CI) represents a novel treatment option to control hemolysis. Due to CI patients (pts) are susceptible to encapsulated bacteria e.g. N. meningitidis. Therefore, meningococcal vaccination on CI is mandatory. In this study serologic response to the tetravalent conjugate vaccine Menveo® was analyzed in CAD pts on eculizumab treatment (DECADE trial) using rabbit serum as complement source (rSBA). Protective rSBA titers varied for meningococcal serogroups and over time reflecting an early decline to even non-protective rSBA titers. These data highlight the importance of serologic analyses under chronic CI. Currently, re-vaccination with a tetravalent meningococcal conjugate vaccine every 3 years is recommended on chronic CI. However, re-vaccination on CI might further rely on serologic analyses, implying even early booster vaccinations similar to adults with (functional) asplenia.

Immunosuppressive therapy (IST) in adult patients with acquired aplastic anemia (AA): A single-center experience over the past 15 years.

OBJECTIVE: Immunosuppressive therapy (IST) with horse anti-thymocyte globulin (hATG) and cyclosporine (CsA) is considered one of the first-line therapies in patients (pts) with acquired aplastic anemia (AA). METHODS: In our single-center, retrospective analysis response rates (RRs) to ATG/CsA at a minimum of 6 mo were evaluated in 67 treatment-naïve (TN) AA pts (52.2% (35/67) females; median age 45 y (range 18-89 y)) being treated at the West German Cancer Center at the Department of Hematology at the University Hospital of Essen between April 2000 and December 2015. RESULTS: Overall 6 mo RRs in TN pts following ATG/CsA were 67.2% (45/67) (5-year OS: 79.5%). In TN hATG-treated pts 6 mo RRs were 75.5% (37/49) (5-year OS: 81%) compared to 44.4% (8/18) (5-year OS 73.5%) following rabbit ATG (rATG). Response to ATG/CsA was dependent of age, absolute reticulocyte count (ARC), and disease severity. Six mo RRs to salvage ATG/CsA in relapsed/refractory (R/R) pts were 37.5% (6/16). CONCLUSION: Our data independently confirm the findings of previous studies that hATG/CsA is superior to rATG/CsA in TN pts. The lack of hATG availability should not result in abstaining it from an indicated ATG therapy, even though ATGAM® is not registered in Germany.

The Role of Whole-Body Magnetic Resonance Imaging (WB-MRI) in Patients with Paroxysmal Nocturnal Hemoglobinuria (PNH).

In PNH thromboembolic events (TEs) represent the leading cause of morbidity and mortality. Between Dec 2013 and Jan 2016 37 PNH patients (pts) (23 PNH, 14 AA/PNH; 51% (19/37) females; median age 44 years, median D-dimer levels 0.22 mg/l) were examined with a whole-body magnetic resonance imaging (WB-MRI) scan at 1.5 T to detect TEs. Pts were treated according to German PNH guidelines, including eculizumab therapy. 64% (24/37) of the pts had no documented TEs prior to observation. Two pts had suspected TEs in their clinical history. 29% of the pts (11/37) had a known history of venous thromboses (deep venous thrombosis (DVT) (5/11), portal venous thrombosis (PVT) (4/11), vena caval thrombosis (VCT) (2/11). A myocardial infarction was reported in one pt, and two had a cerebral venous sinus thrombosis (CVST) or a thalamic infarction. Six pts (16%) had at least two prior TEs. In pts with prior TEs no progression of the existing TEs was observed. In pts on eculizumab and prior TEs as well as treatment-naïve pts silent bone and renal infarctions were detected. Furthermore, a clinically non-critical arterial occlusion was identified. WB-MRI scans present a novel, non-invasive method to assess the complete vascular status of PNH pts and allow the detection of previously undiagnosed vascular complications, affecting treatment indications and regimens.

Persisting hyperbilirubinemia in patients with paroxysmal nocturnal hemoglobinuria (PNH) chronically treated with eculizumab: The role of hepatocanalicular transporter variants.

BACKGROUND: Eculizumab-treated paroxysmal nocturnal hemoglobinuria (PNH) patients (pts) show a dramatic decrease in serum lactate dehydrogenase (LDH) activities and bilirubin concentrations. However, some pts remain hyperbilirubinemic, possibly indicating an inadequate response due to extravascular hemolysis. METHODS: Mutation analyses of hepatocanalicular transporter/nuclear receptor variants (ABCB4, ABCB11, ATP8B1, NR1H4) were performed in eight (five of eight males; mean age 38 years [range 26-68 years]) out of the 174 pts with PNH/-clone at our department due to a persistent increase in total bilirubin concentrations (median 3.4 mg/dL; range 2.1-8.1 mg/dL) during chronic eculizumab treatment and normal/or slightly increased serum aminotransferase activities. Median observation time was 70.1 months (range 10.6-135.2 months). All pts were treated according to German PNH guidelines. RESULTS: Homozygous and heterozygous procholestatic variants in the ABCB4, ABCB11, and ATP8B1 genes were identified in all eight pts. All carried the common ABCB4 c.787A>T polymorphism. The A(TA)7 TAA variant in the UGT1A1 promoter causing Gilbert syndrome was detected in three pts (5/8). CONCLUSIONS: Hyperbilirubinemia in PNH pts treated with eculizumab might not only be due to an insufficient response but rather a combination of mutations in hepatocanalicular transporter variants, Gilbert syndrome, and extravascular hemolysis. Our findings warrant further studies concerning transporter and enzyme variants in PNH to determine their clinical significance.

Serologic response to meningococcal vaccination in patients with paroxysmal nocturnal hemoglobinuria (PNH) chronically treated with the terminal complement inhibitor eculizumab.

Eculizumab is indicated for the therapy of patients with symptomatic paroxysmal nocturnal hemoglobinuria (PNH). Due to inhibition of terminal complement cascade, patients on eculizumab are susceptible to Neisseria meningitidis infections. The two mainstays to reduce the risk of infection are vaccination and antibiotic prophylaxis. In this retrospective study, serologic response was analyzed after vaccination with a meningococcal vaccine in 23 PNH patients (median age 36 years; range 25 - 88 years; 15 males, 8 females) by measuring serum bactericidal assay (SBA) using rabbit complement (rSBA) titers against meningococcal serogroups A, C, W, and Y. Serologic protection was defined by an rSBA titer ≥1:8. Forty-three percent (10/23) were vaccinated more than once due to chronic eculizumab treatment. Overall serologic response for the meningococcal serogroups was A: 78% (18/23), C: 87% (20/23), W: 48% (11/23), and Y: 70% (16/23). No meningococcal infections have been observed. As immunological response to vaccines varies, the use of serologic response analyses is warranted. Re-vaccination with a tetravalent conjugate vaccine under eculizumab therapy every 3 years is essential or should be based on response rates. If meningococcal infection is suspected, standby therapy with ciprofloxacin and immediate medical evaluation are recommended. The novel vaccines covering serogroup B may even further reduce the risk for infection.

The determinants of bicycle helmet use: evidence from Germany.

Previous research has shown that the risks of serious injury or death from bicycling can be mitigated by the decision to wear a helmet. Drawing on a nationwide household survey conducted in 2008 in Germany, this analysis investigates the determinants of voluntary helmet use through a combination of descriptive analyses and econometric methods, the latter relying on variants of the probit- and heteroskedastic probit model. Confirming results uncovered elsewhere in the literature, we find that household demographics, residential location, and riding patterns are significant correlates of helmet use. Contrasting with other studies, however, we also find that women are significantly less likely to use a helmet than men, a discrepancy that holds over most of the adult life-cycle. The paper concludes by highlighting the scope for designing strategic information campaigns to promote helmet use.