Severe Hemolysis Research Articles

Study of Some Predictors of Severe Hemolysis in Children with Glucose-6-Phosphate Dehydrogenase Deficiency

AbstractBackground: Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency is one of the most common inherited disorders of mankind; more than 400 million people are affected worldwide, and it is a major health problem in Egypt.Aim of Work: To study some predictors of severe hemolysis in children with glucose-6-phosphate dehydrogenase deficiency and the degree of DNA damage in these patients.Patients and Methods: Seventy-two patients with G6PD deficiency admitted with acute hemolytic attacks to Diarb Negm Central Hospital-Sharkia Governorate, Egypt-over a period of 1 year from 1st May 2014 to 30th April 2015. We collected demographic data, details of signs and symptoms; special attention was given to history of fava bean ingestion, history of drug use or history of recent infection, history of neonatal jaundice, family history of G6PD deficiency disease, abdominal pain, vomiting or fever at admission and the results of tests for hemoglobin, reticulocytic count, hepatic function, G6PD enzyme activity and detection of DNA damage by DNA extraction, purification and agarose gel electrophoresis. We classified patients into mild and severe groups based on hemoglobin levels at admission. The mild cases were consid-ered as the control group.Results: 72 children with G6PD deficiency admitted with acute hemolytic attacks were included in this study, 52 (72%) patients with severe hemolysis and 20 (28%) patients with mild hemolysis (control group). There were no statistically significant differences in many factors between the two groups, but some factors were detected to have statistical significance for severe hemolysis included younger age (p<.0001), male gender (p<.0001), presence of fever at admission (p<.0001), presence of vomiting (p<.0001) and abdominal pain (p<.0001) during the attack, higher Alkaline Phosphatase (ALP) (p <.0001), Aspartate Aminotransferase (AST) (p<.0001), Lactate Dehydrogenase (LDH) (p<.0001) and Total Serum Bilirubin (TSB) (p<.05). DNA damage was significantly higher in the severe cases compared to the mild cases (p<.0001).Conclusion: Severe hemolysis can be predicted during hemolytic episodes in children with G6PD deficiency by young age, male gender, the presence of abdominal pain, vomiting and fever, high levels of ALP, AST, LDH enzymes and elevated TSB. This severe hemolysis predisposes patients to higher degree of DNA damage.

Autoimmune hemolytic anemia.

The diagnosis of autoimmune hemolytic anemia (AIHA) can be made with a stepwise approach that aims to identify laboratory and clinical evidence of hemolysis and then determine the immune nature of hemolysis with the direct anti-globulin test. Once alternative causes for these findings have been excluded, AIHA is established, and the clinician must search for secondary causes, as well as identify the type of AIHA. Rituximab is now the preferred second-line treatment for primary warm AIHA and first-line treatment for primary cold agglutinin disease (CAD), either as monotherapy or combined with bendamustine. Complement inhibitors have shown utility in stabilizing AIHA patients with acute severe hemolysis. Future prospects are discussed and include the C1s inhibitor BIVV009 (sutimlimab) that is now entering phase 3 studies for CAD.

Lung Function Impairment in Pediatric Subjects with Sickle Cell Anemia from Nigeria Is Associatede with Associated Low Steady Haemoglobin

Low hemoglobin (Hb) level at steady state in subjects with sickle cell anemia (SCA) may indicate severe chronic hemolysis and might be related to a more severe course of disease.In this study we investigated the hypothesis that low hemoglobin at steady state may be associated with higher rate of lung function impairment in children and adolescents with SCA.MethodsIn this cross-sectional study black African subjects with SCA (Hb phenotype SS) aged 6 to 18 years followed at the Barau Dikko Teaching Hospital, Kaduna, Nigeria, underwent spirometry and anthropometry measures. A recent Hemoglobin level at steady state was recorded for each patient. Caregivers or patients were interviewed through a questionnaire investigating a history of asthma or acute chest syndrome (ACS) and frequency of pain crises in the last year that required analgesics for at least 24 hours. Exclusion criteria were: the lack of recorded complete blood count (CBC) performed in the last 6 months, respiratory symptoms or feeling unwell on the test day, SCA-related acute events (e.g., pain crises) in the last two weeks or a blood transfusion or an ACS episode in the last month. A portable Easy-on-PC spirometer (ndd, Zurich, Switzerland) was used. Data were included if at least two forced expiratory manoeuvres met the ATS/ERS acceptability and repeatability criteria adapted for children (Miller MR, ERJ 2005; Kirkby J, Pediatr.Pulmonol.2008). Spirometry z-scores and percentage of predicted for FEV1, FVC and FEV1/FVC were derived according to the GLI-2012 reference equations for African Americans (Quanjer PH, ERJ2012). Spirometry patterns were classified as normal, obstructive (zFVC ≥ 1.64 + zFEV1/FVC < -1.64), restrictive (zFVC < -1.64 + zFEV1/FVC ≥ -1.64) or mixed (zFVC < -1.64 + zFEV1/FVC < -1.64) and a FEV1 < 70% of predicted was considered indicative of lung end-organ disease (Kassim AA et al, Blood. 2015 Sep 24;126(13):1544-50). Group comparison between patients with Hb level < 7.5 g/dL versus Hb ≥7.5 g/dL were tested using unpaired t test, χ2 or Fisher's exact test as appropriate. The relationship between Hb values and spirometry outcomes was explored through logistic and linear regression models. P-value < 0.05 was adopted as representing a statistically significant difference. Analyses were conducted using the software STATA and Graphpad Prism 7.ResultsA total of 186 subjects with SCA were initially enrolled. Only one child was on hydroxyurea. After exclusions, data from 126 patients (mean ± SD age of 11.5 ± 3.1 yr., 53% boys) were retained for the final analysis. Mean ± SD Hb value was 7.8±0.9 g/dL (range 5.6 to 10.9). Frequency of low Hb (< 7.5 g/dL) at steady state was 30.9% (39/126).Mean FEV1 and FVC z-scores were lower and frequency of FEV1 < 70% of predicted was higher in patients in the low Hb group compared to those with Hb ≥7.5 g/dL though differences were not statistically significant (table 1). Prevalence of restrictive spirometry pattern, possibly suggesting restrictive lung disease, was significant higher in patients with Hb level < 7.5 g/dL (17/39, 43.5%) than in those with Hb ≥7.5 g/dL (20/87, 22.9%) (p = 0.01; table 1).The odds ratio for restrictive spirometry pattern in presence of Hb level <7.5 g/dL was 2.5 (95% CI 1.1 to 5.7; p = 0.03). In a linear regression model (figure 1) the FVC z-score resulted significantly related to the Hb level with an increase of 0.17 z-scores for each point of Hb (95% CI 0.01 to 0.34, p = 0.04; R2 = 0.03).Frequency of asthma, pain crises and previous acute chest syndrome did was similar between the two groups (data not showed)ConclusionsIn Nigerian pediatric patients with sickle cell anemia a hemoglobin level < 7.5 g/dL at steady state was associated with a 2.5 higher risk of presenting a restrictive spirometry pattern and with a higher frequency of end-organ lung disease (FEV1 < 70% of predicted). Low hemoglobin levels in wellbeing may depend on intense chronic haemolysis that could worsen microangiopathy, inflammation and ischemia and reperfusion injury in the lungs, potentially determining a precocious onset of restrictive lung disease.These preliminary data seem to indicate that a low Hb level at steady state in African pediatric patients with sickle cell anemia is associated with more severe lung impairment and should prompt respiratory assessment with lung function when found. [Display omitted] DisclosuresInusa:Novartis plc: Honoraria, Research Funding, Speakers Bureau; Astrazeneca: Consultancy.

Hemoglobin S Induces Exposure of Red Blood Cell Membrane Skeleton Microdomains Bearing Mannose That Stimulate Phagocytosis By Macrophages: A Molecular Basis for Hemolysis in Sickle Cell Disease but Protection Against Plasmodium Falciparum malaria

Heterozygosity for Hemoglobin (Hb) S, sickle cell trait (SCT), affects over 40 million people and confers resistance to severe infection by Plasmodium falciparum. Homozygosity for HbS, or compound heterozygosity with certain other alleles of Hb, affects over 4 million individuals and causes sickle cell disease (SCD). Hemolytic anaemia is a prominent feature of SCD and is mainly extravascular, mediated by hepatic and splenic macrophages. No ligands for this process have been identified. As many macrophage phagocytic receptors recognise carbohydrates, we surveyed surface glycan expression by sickle cells using a panel of 8 lectins and flow cytometry. Most glycans were similar to those of healthy red blood cells (RBC), except much higher expression of terminal mannose.We investigated the structural basis for these residues using glycomic mass spectroscopy, which showed them to be N-linked high (Man5-9GlcNAc2) mannoses, a surprising conclusion as these are usually intermediates in the formation of complex glycans and not displayed on cell surfaces. High resolution microscopy revealed the mannose residues to be carried in discrete microdomains on the surfaces of sickle cells. These structures were absent on the surfaces of healthy RBC, instead being present in the membrane skeleton under the cell surface. Lectin blots and immunoprecipitation showed the mannoses to co-migrate predominantly with spectrin.We showed these mannose-bearing structures were able to stimulate phagocytosis of RBC by using a peripheral blood derived macrophage uptake assay. Sickle RBC were taken up at high rates compared to healthy RBC and this could be inhibited by congeners of mannose. We identified the importance of a cognate ligand (CD206: the mannose receptor) using blocking antibodies and knockdown of CD206 expression using siRNA.The in vivo and pathogenic relevance of mannose exposure was investigated by taking advantage of the heterogeneity of hemolysis in SCD. RBC with SCD (n=94), SCT (n=57) and healthy individuals (n=54) were assayed for mannose exposure by flow cytometry. SCT and healthy RBC showed no mannose exposure but high levels were found on HbSS RBC (p<0.0001). Co-incident inheritance of HbSS with higher HbF values and alleles encoding alpha-thalassaemia resulted in lower surface mannose values. Overall, markers of hemolysis (RBC count, haemoglobin, reticulocyte count) correlated well with mannose exposure (Spearman correlation coefficients -0.68, -0.40, 0.37; p=0.0001, 0.0032, 0.0063 respectively). Plasma LDH is a marker of intravascular hemolysis and correlated with overall hemolysis within SCD (r=-0.25, p=0.016), but not mannose exposure (r=0.14, p=0.19). Thus mannose exposure correlated only with extravascular hemolysis.Identification of a ligand pair mediating rapid clearance of sickle cells raised the possibility that they also mediate enhanced clearance of SCT RBC infected by malarial parasites. Indeed, P. falciparum cultures induced mannose expression at the pigmented trophozoite and schizont stages in infected HbAA RBCs, at levels corresponding to mild hemolysis in SCD. Mannose expression in infected HbAS RBCs was even higher, with levels corresponding to severe hemolysis in SCD.Infection with P. falciparum and selection for HbS arose only recently in human evolution, raising the question of what the physiological triggers for this mechanism are. Infection with malarial parasites causes oxidative stress. We therefore subjected healthy RBC to copper sulphate, which resulted in surface mannose exposure as well as uptake by macrophages. Oxidized SCT RBC displayed more mannose than oxidized healthy RBC.Thus, we have identified a new cell surface ‘eat me’ signalling mechanism that allows inspecting macrophages to engage with the rigid membrane skeleton and phagocytose the mannose displaying cell. The mechanism is stimulated by HbS: when present in high concentrations, the mechanism is activated constitutively, resulting in sickle cell anaemia. Heterozygosity for HbS is insufficient by itself to trigger mannose exposure. However, the mechanism is primed so that oxidative stress associated with infection by P. falciparum causes greater mannose display, increased parasitized cell clearance and protection against severe malaria. These findings should allow the design of inhibitors of sickle cell haemolysis and inducers of protection against malaria. DisclosuresCao:University of Aberdeen: Patents & Royalties. Barker:University of Aberdeen: Patents & Royalties. Vickers:University of Aberdeen: Patents & Royalties; GSK: Equity Ownership.

Point-of-Care Testing for G6PD Deficiency: Opportunities for Screening.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, an X-linked genetic disorder, is associated with increased risk of jaundice and kernicterus at birth. G6PD deficiency can manifest later in life as severe hemolysis, when the individual is exposed to oxidative agents that range from foods such as fava beans, to diseases such as typhoid, to medications such as dapsone, to the curative drugs for Plasmodium (P.) vivax malaria, primaquine and tafenoquine. While routine testing at birth for G6PD deficiency is recommended by the World Health Organization for populations with greater than 5% prevalence of G6PD deficiency and to inform P. vivax case management using primaquine, testing coverage is extremely low. Test coverage is low due to the need to prioritize newborn interventions and the complexity of currently available G6PD tests, especially those used to inform malaria case management. More affordable, accurate, point-of-care (POC) tests for G6PD deficiency are emerging that create an opportunity to extend testing to populations that do not have access to high throughput screening services. Some of these tests are quantitative, which provides an opportunity to address the gender disparity created by the currently available POC qualitative tests that misclassify females with intermediate G6PD activity as normal. In populations where the epidemiology for G6PD deficiency and P. vivax overlap, screening for G6PD deficiency at birth to inform care of the newborn can also be used to inform malaria case management over their lifetime.

G6PD deficiency, primaquine treatment, and risk of haemolysis in malaria-infected patients

BackgroundThe incidence of malaria in the Americas has decreased markedly in recent years. Honduras and the other countries of Mesoamerica and the island of Hispaniola have set the goal of eliminating native malaria by the year 2020. To achieve this goal, Honduras has recently approved national regulations to expand the possibilities of a shortened double dose primaquine (PQ) treatment for vivax malaria. Considering this new shortened anti-malarial treatment, the high frequency of G6PDd genotypes in Honduras, and the lack of routinely assessment of the G6PD deficiency status, this study aimed at investigating the potential association between the intake of PQ and haemolysis in malaria-infected G6PDd subjects.MethodsThis was a prospective cohort and open-label study. Participants with malaria were recruited. Plasmodium vivax infection was treated with 0.25 mg/kg of PQ daily for 14 days. Safety and signs of haemolysis were evaluated by clinical criteria and laboratory values before and during the 3rd and 7th day of PQ treatment. G6PD status was assessed by a rapid test (CareStart™) and two molecular approaches.ResultsOverall 55 participants were enrolled. The frequency of G6PD deficient genotypes was 7/55 (12.7%), where 5/7 (71.4%) were hemizygous A− males and 2/7 (28.6%) heterozygous A− females. Haemoglobin concentrations were compared between G6PD wild type (B) and G6PDd A− subjects, showing a significant difference between the means of both groups in the 3rd and 7th days. Furthermore, a statistically significant difference was evident in the change in haemoglobin concentration between the 3rd day and the 1st day for both genotypes, but there was no statistical difference for the change in haemoglobin concentration between the 7th day and the 1st day. Besides these changes in the haemoglobin concentrations, none of the patients showed signs or symptoms associated with severe haemolysis, and none needed to be admitted to a hospital for further medical attention.ConclusionsThe findings support that the intake of PQ during 14 days of treatment against vivax malaria is safe in patients with a class III variant of G6PDd. In view of the new national regulations in the shortened treatment of vivax malaria for 7 days, it is advisable to be alert of potential cases of severe haemolysis that could occur among G6PD deficient hemizygous males with a class II mutation such as the Santamaria variant, previously reported in the country.

Surfactant Free Delivery of Docetaxel by Poly[(R)-3-hydroxybutyrate-(R)-3-hydroxyhexanoate]-Based Polymeric Micelles for Effective Melanoma Treatments.

Docetaxel (DTX) is a new semisynthetic chemical in the taxoid family and serves a wide spectrum of chemotherapeutics. Current commercial formulation of DTX is based on the addition of the nonionic surfactants (i.e., ethanol and Tween 80), which are reported to cause severe hemolysis, hypersensitivity reactions, or neurotoxic toxicity and greatly hinders patient tolerance or compliance. In this report, a novel low-toxic, biodegradable, and amphiphilic poly[(R)-3-hydroxybutyrate-(R)-3-hydroxyhexanoate] (PHBHx)-based polyurethane (a copolymer made of hydrophobic PHBHx with biocompatible D-3-hydroxybutyric acid as degradation product, thermosensitive polypropylene glycol (PPG), and hydrophilic polyethylene glycol (PEG) segments) with nanosized micelle formation ability to encapsulate DTX, as a surfactant free formulation, is reported. Interestingly, this DTX-loaded poly(PHBHx/PEG/PPG urethane) micelle formulation with >90% drug loading efficiency shows significantly improved DTX solubility in aqueous medium, reduced hemolysis for better blood compatibility, and increased drug uptake in A375 melanoma cells, which provides the possibility of systematic delivery of DTX. As a proof-of-concept, an A375 melanoma xenograft mouse model is established to verify the therapeutic effect of this DTX-loaded poly(PHBHx/PEG/PPG urethane) micelle formulation, indicating the promising application of PHBHx-based polymeric nanosized micelle as a surfactant free formulation of chemotherapeutics which might greatly be beneficial for controllable delivery of pharmaceutics and cancer therapy.

56 - Excess circulating free heme triggers immense elevation in plasma xanthine oxidase activity

Heme, an iron-containing compound and critical prosthetic group for metalloproteins, is found most commonly as an element of hemoglobin. Excess circulating heme is a key driver of hemolytic diseases including thalassemia, malaria, sickle cell disease, sepsis as well as a side effect of transplantation and cardiac bypass. Severe hemolysis (heme crisis) saturates heme degradation pathways such as hemopexin leading to abundant circulating free heme that can directly generate reactive oxygen species (ROS) and/or stimulate elevation in enzymatic sources of ROS, ultimately leading to overt tissue damage. A key enzymatic source of ROS reported to be upregulated in sickle cell disease is xanthine oxidase (XO). As such, we investigated the relationship between circulating XO activity and heme crisis in mice. Both 24 hour survival and plasma XO activity were assessed in C57BL6/J mice injected (tail-vein) with hemin (0-100 μmol/kg). Hemin dose-dependently reduced survival (100% (25 μmol/kg), 87% (50 μmol/kg), 12% (70 μmol/kg) and 0% (100 μmol/kg)). Hematological analysis revealed an increase in monocyte recruitment and diminished platelet counts with increasing doses of hemin. Doses of 50 and 70 μmol/kg hemin elevated plasma XO activity 20-fold and 39-fold, respectively compared to controls and correlated with substantial loss of hepatic XO. Histological analysis (H&E staining) also indicated that liver tissue from mice injected with 50 μmol/kg hemin demonstrated significant alterations in tissue organization. In conclusion, heme crisis induces extensive hepatocellular release of XO into the circulation where it may actively participate in the pathologic process. To validate this assumption, we have generated a liver-specific XO knockout and are currently investigating mechanisms underpinning heme crisis-associated hepatocellular release of XO as well as the impact of circulating XO on cardiovascular function. These ongoing experiments may serve to identify novel clinical strategies to address heme crisis.

Dietary restrictions for people with glucose-6-phosphate dehydrogenase deficiency.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme deficiency in the world and renders those affected susceptible to potentially severe oxidative hemolysis. Although the resulting hemolysis is most often associated with drug exposure, it has also been reported after consumption of certain foods. With the exception of review articles that reiterated the historical knowledge that fava beans can provoke severe oxidative hemolysis in individuals with G6PD deficiency, very few articles have examined the safety of other food ingredients and food additives for people with G6PD deficiency. Some articles that associated specific foods with hemolysis appeared to be speculative and based on limited information. The objective of this review was to examine the association between foods, including food additives, and the triggering factors of acute hemolysis. The literature was searched for studies and case reports on food consumption and G6PD deficiency. In this review, fava beans were found to be the only food for which there is conclusive clinical evidence linking the risk of hemolytic anemia to individuals with G6PD deficiency. Food additives, at their permitted level of use in North America, can be consumed safely by most patients with G6PD deficiency.

Epidemiology and outcome of acute kidney injury due to venomous animals from a subtropical region of India

Aim: To study the epidemiology and outcome of acute kidney injury (AKI) caused by venomous animals.Methods: A retrospective study of patients admitted at Indira Gandhi Medical College Hospital, Shimla, with AKI due to venomous animals over a period of 15 years (January 2003–December 2017). Medical records were evaluated for patient information on demographic factors, clinical characteristics, complications, and outcome. Outcomes of requirement for intensive care unit (ICU) support, treatment with dialysis, survival, and mortality were analyzed. The survival and non-survival groups were compared to see the difference in the demographic factors, laboratory results, clinical characteristics, and complications.Results: One hundred and eighty-one patients were diagnosed with AKI caused by venomous creatures. Mean age was 44 ± 15.4 years, and the majority (54.1%) was women. Snakebite (77.9%) and wasp stings (19.9%) were the leading causes of AKI. Clinical details were available in 148 patients. The median duration of arrival at hospital was two days. 81.8% had oliguria, and 54.7% had a history of hematuria or having passed red or brown colored urine. The hematological and biochemical laboratory abnormalities were as follows: anemia (75%), leukocytosis (75.7%), hyperkalemia (35.8%), severe metabolic acidosis (46.6%), hepatic dysfunction (54.7%), hemolysis (85.8%), and rhabdomyolysis (65.5%). Main complications were as follows: gastrointestinal bleed (9.5%), seizure/encephalopathy (10.8%), and pneumonia/acute respiratory distress syndrome (ARDS) (11.5%). 82.3% of the patients required dialysis. 154 (85.1%) patient survived, and 27 (14.9%) patients died. As compared to the survival group, the white blood cell count, serum bilirubin, aspartate aminotransferase, alanine aminotransferase, creatine kinase, and lactate dehydrogenase were significantly higher, and serum albumin levels were significantly lower in patients who died. The proportion of patients with leukocytosis, hyperkalemia, metabolic acidosis, pneumonia/ARDS, seizure/encephalopathy, need for ICU support, and dialysis was significantly higher in patients who died.Conclusions: Snakebite and multiple Hymenoptera stings (bees and wasps) were the leading causes of AKI due to venomous animals. AKI was severe, a high proportion required dialysis, and the mortality was high.

Clinical Features and Laboratory Data Analysis of Glucose-6- Phosphate Dehydrogenase Deficiency

To explore clinical features and laboratory data of glucose-6-phosphate dehydrogenase（G6PD）deficiency and to investigate the relationship between them. Clinical data of 43 patients with G6PD deficiency was analyzed, the statistical method was applied to investigate the relationship between clinical features and laboratory data. Among 43 patients，neonatal jaundice occurred as the first symptom in 10 cases，while acute hemolytic anemia occurred as the first symptom in 23 cases. The major clinical symptoms of G6PD deficiency included icteric skin and/or sclera，dark urine，fever，gastrointestinal symptoms，fatigue and lethargy. Symptoms of 26 patients were caused by obvious inducement，including fava beans（61.5%），infection（34.6%）and miocardial infarction（3.8%）. All of 43 patients showed decreased G6PD activity，while the level of their indirect serum bilirubin（IBIL）was positively correlated with reticulocyte percentage（Ret%，r=0.5881，P=0.013） and mean corpuscular volume（MCV，r=0.6854，P=0.0024）. Patients with neonatal jaundice as the first symptom，showed higher level of Ret%（P<0.01）and MCV（P<0.001）and low RBC count（P<0.01）and low Hb level（P<0.01）. as compard with patients with acute hemolytic anemia as first symptome. Neonatal jaundice and acute hemolytic anemia are common clinical features of G6PD deficiency. Laboratory results of IBIL，Ret% and MCV have auxiliary value to evaluate the severity of hemolysis induced by G6PD deficiency. Patients with neonatal jaundice as their first symptom show more severe hemolysis than those only suffered from acute hemolytic anemia.

Hypertension, Anxiety, and Blood-Brain Barrier Permeability Are Increased in Postpartum Severe Preeclampsia/Hemolysis, Elevated Liver Enzymes, and Low Platelet Count Syndrome Rats.

Hypertension and inflammation during pregnancy are suggested to contribute to the development of postpartum depression and anxiety. Using a rat model of severe preeclampsia and hemolysis, elevated liver enzymes, and low platelet count syndrome, which displays both hypertension and inflammation during pregnancy, we evaluated whether rats were prone to develop depression or anxiety in the postpartum period. On gestational day 12, miniosmotic pumps infusing sFlt-1 (soluble fms-like tyrosine kinase-1) and sEng (soluble endoglin) were placed into rats, a subset of these rats was infused with 2 mg/kg of Orencia (abatacept) the following day to determine whether immune suppression via T-cell depletion prevented any changes in maternal depression or anxiety-like behavior. All rats, including normal pregnant (NP) controls, delivered between gestational days 21 and 22. Postpartum severe preeclamptic rats buried significantly more marbles compared with NP rats ( P=0.002) and Orencia-treated rats ( P=0.05). Severe preeclamptic rats spent significantly more time in closed arms of the elevated plus maze compared with NP rats ( P=0.009) and Orencia-treated rats ( P=0.05). Severe preeclamptic rats were hypertensive compared with NP ( P=0.03) and Orencia-treated rats ( P=0.01). Finally, severe preeclamptic rats had increased blood-brain barrier permeability compared with NP rats ( P=0.03), which was reversed in Orencia-treated rats ( P=0.008). These results suggest that severe preeclampsia/hemolysis, elevated liver enzymes, and low platelet count syndrome during pregnancy contributes to an increase in anxiety-like behavior, blood-brain barrier permeability, and hypertension in the postpartum. The current results suggest that T-cell suppression during pregnancy can also help prevent chronic hypertension and increased anxiety in the postpartum period.

Evans syndrome: clinical perspectives, biological insights and treatment modalities.

Evans syndrome (ES) is a rare and chronic autoimmune disease characterized by autoimmune hemolytic anemia and immune thrombocytopenic purpura with a positive direct anti-human globulin test. It is classified as primary and secondary, with the frequency in patients with autoimmune hemolytic anemia being 37%–73%. It predominates in children, mainly due to primary immunodeficiencies or autoimmune lymphoproliferative syndrome. ES during pregnancy is associated with high fetal morbidity, including severe hemolysis and intracranial bleeding with neurological sequelae and death. The clinical presentation can include fatigue, pallor, jaundice and mucosal bleeding, with remissions and exacerbations during the person’s lifetime, and acute manifestations as catastrophic bleeding and massive hemolysis. Recent molecular theories explaining the physiopathology of ES include deficiencies of CTLA-4, LRBA, TPP2 and a decreased CD4/CD8 ratio. As in other autoimmune cytopenias, there is no established evidence-based treatment and steroids are the first-line therapy, with intravenous immunoglobulin administered as a life-saving resource in cases of severe immune thrombocytopenic purpura manifestations. Second-line treatment for refractory ES includes rituximab, mofetil mycophenolate, cyclosporine, vincristine, azathioprine, sirolimus and thrombopoietin receptor agonists. In cases unresponsive to immunosuppressive agents, hematopoietic stem cell transplantation has been successful, although it is necessary to consider its potential serious adverse effects. In conclusion, ES is a disease with a heterogeneous course that remains challenging to patients and physicians, with prospective clinical trials needed to explore potential targeted therapy to achieve an improved long-term response or even a cure.

Evaluation of biomimetically synthesized mesoporous silica nanoparticles as drug carriers: Structure, wettability, degradation, biocompatibility and brain distribution

Herein, three kinds of mesoporous silica nanoparticles (BMSs) were biomimetically synthesized by using heterocyclic amino acid derivatives as template and their the basic capacity in being drug carriers that covered structure, wettability, degradation, brain uptake, hemocompatibility and toxicity were systematically evaluated. The results indicated that BMSs were kinds of spherical nanoparticles with good biocompatibility. Their in vitro and in vivo behaviors, including degradation, biodistribution and biocompatibility were mainly governed by the wettability which was closely related to the structure and pore diameter of mesoporous silica nanoparticles. BMSs can degrade completely under simulated physiological environments through a time period of 2–13 weeks. They showed the tendency of brain distribution, and the distribution amount peaked at 4 h post administration. Particularly, Trp-BMS (BMS templated by C16-l-tryptophan) with the largest amount of OH groups on the surface exhibited highest wettability, fastest degradation rate and the lowest brain distribution ability. Besides, His-BMS (BMS templated by C16-l-histidine) and Pro-BMS (BMS templated by C16-l-poline) were silica materials with good biocompatibility. Both in vitro and in vivo studies uncovered no significantly toxicity for BMSs and they were proved to be safe when they circulated into the blood. However, Trp-BMS might induce severe hemolysis and cell cycle arrest due to the high wettability. It is believed that appropriate wettability is required for the in vivo application of nanomaterials and the in vivo evaluation of mesoporous silica nanoparticles will provide useful information for understanding the underlining toxicity of biomaterials and bring new insights on designing efficient drug delivery systems.

Severe hemolysis associated with left ventricular outflow tract stenosis following aortic valve replacement

Severe hemolysis associated with left ventricular outflow tract stenosis following aortic valve replacement

Post-mortem in situ stability of serum markers of cerebral damage and acute phase response.

The aim of the given study was to test the in situ stability of biochemical markers of cerebral damage and acute phase response in the early post-mortem interval to assess their usability for forensic pathology. A monocentric, prospective study investigated post-mortem femoral venous blood samples at four time points obtained within 48h post-mortem starting at the death of 20 deceased, using commercial immunoassays for the ten parameters: S100 calcium-binding protein B (S100B), glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE), brain-derived neurotrophic factor (BDNF), interleukin-6 (IL-6), C-reactive protein (CRP), procalcitonin (PCT), ferritin, soluble tumor necrosis factor receptor type 1 (sTNFR1), and lactate dehydrogenase (LDH). Significant changes in serum levels were observed only later than 2h after death for all markers. Inter-laboratory comparability was high, and intra-assay precision was sufficient for most markers. Most of the biomarker levels depended on the severity of hemolysis and lipemia but were robust against freeze-thaw cycles. Serum levels increased with longer post-mortem intervals for S100B, NSE, ferritin, sTNFR1, and LDH (for all p < 0.001) but decreased over this period for CRP (p = 0.089) and PCT (p < 0.001). Largely unchanged median values were found for GFAP (p = 0.139), BDNF (p = 0.106), and IL-6 (p = 0.094). Serum levels of CRP (p = 0.059) and LDH (p = 0.109) did not differ significantly between the final ante-mortem (resuscitation) and the first post-mortem sample (moment of death). Collecting the post-mortem blood sample as soon as possible will reduce the influence of post-mortem blood changes. Serum GFAP for detection of cerebral damage as well as serum IL-6 and CRP as proof of acute phase response seemed to be preferable due to their in situ stability in the first 2days after death.

Immune hemolysis secondary to injection of contrast medium.

Drug-induced immune hemolytic anemia (DIIHA) is a rare but sometimes severe side effect. We describe the case of a 32-year-old patient who presented a cardiovascular collapse and a severe hemolysis secondary to the injection of iomeprol, a contrast medium, after a carcinologic surgery. The evolution was favorable after blood transfusion and short catecholamine support. The biology showed drug-dependent antibodies after incubation with iomeprol. This case is the second report of DIIHA with iomeprol.

Impairment of Nitric Oxide Pathway by Intravascular Hemolysis Plays a Major Role in Mice Esophageal Hypercontractility: Reversion by Soluble Guanylyl Cyclase Stimulator.

Paroxysmal nocturnal hemoglobinuria (PNH) patients display exaggerated intravascular hemolysis and esophageal disorders. Since excess hemoglobin in the plasma causes reduced nitric oxide (NO) bioavailability and oxidative stress, we hypothesized that esophageal contraction may be impaired by intravascular hemolysis. This study aimed to analyze the alterations of the esophagus contractile mechanisms in a murine model of exaggerated intravascular hemolysis induced by phenylhydrazine (PHZ). For comparative purposes, sickle cell disease (SCD) mice were also studied, a less severe intravascular hemolysis model. Esophagus rings were dissected free and placed in organ baths. Plasma hemoglobin was higher in PHZ compared with SCD mice, as expected. The contractile responses produced by carbachol (CCh), KCl, and electrical-field stimulation (EFS) were superior in PHZ esophagi compared with control but remained unchanged in SCD mice. Preincubation with the NO-independent soluble guanylate cyclase stimulator 3-(4-amino-5-cyclopropylpyrimidin-2-yl)-1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridine (BAY 41-2272; 1 μM) completely reversed the increased contractile responses to CCh, KCl, and EFS in PHZ mice, but responses remained unchanged with prior treatment with NO donor sodium nitroprusside (300 μM). Protein expression of 3-nitrotyrosine and 4-hydroxynonenal increased in esophagi from PHZ mice, suggesting a state of oxidative stress. In endothelial nitric oxide synthase gene-deficient mice, the contractile responses elicited by KCl and CCh were increased in the esophagus but remained unchanged with the intravascular hemolysis induced by PHZ. In conclusion, our results show that esophagus hypercontractile state occurs in association with lower NO bioavailability due to exaggerated hemolysis intravascular and oxidative stress. Moreover, our study supports the hypothesis that esophageal disorders in PNH patients are secondary to intravascular hemolysis affecting the NO-cGMP pathway.

HLA-DQB1*0201 phenotype and severe primary RhD immunization

Purpose of Investigation: Although post-delivery administration of anti-D immunoglobulin (anti-D Ig) and antenatal prophylaxis the residual prevalence of RH alloimmunization is due to an incomplete application of the guidelines or to clinical conditions that foster mechanisms of immunization. Materials and Methods: The authors report a case of devastating RhD alloimmunization in a secundipara, group 0 Rh negative, without potentially immunizing events. Results: Anti-D antibodies were screened at 6/2 and at 13/4 weeks and were found negative. Fetal echocardiography at 25/0 weeks showed dilated right cardiac sections and a mild pericardial effusion. Titer of anti-D antibodies was (1:1024) with negative Kleihauer-Betke. At 27/0 weeks she had an increase of anti-D antibody titer (1:8192), peak systolic velocity in the middle cerebral artery suggested severe fetal anemia. A positive HLA-DQB1 allele *0201 was found, and she gave birth to an infant with severe immune-mediated hemolysis (HB: 3.8 g/dl) who was discharged 62 days after birth due to perinatal complications. Conclusion: HLA-DQB1*0201 phenotyping can improve the surveillance and treatment of non-sensitized D negative patients.

Post-traumatic thrombotic microangiopathy following pelvic fracture treated with transcatheter arterial embolization: a case report

BackgroundThrombotic microangiopathy is caused by various conditions, but few cases secondary to trauma have been reported. We present the rare case of a patient with thrombotic microangiopathy-induced high-impact trauma with hemorrhagic shock.Case presentationAn 86-year-old Japanese woman was transferred to our hospital after a traffic accident. A whole-body computed tomography scan revealed pelvic fractures with massive extravasation. She received a blood transfusion and emergency angiographic embolization. On post-traumatic day 1, she showed unexplained severe hemolysis, thrombocytopenia, and renal failure despite her stable condition. Disseminated intravascular coagulation was excluded because her activated partial thromboplastin time and prothrombin time-international normalized ratio were normal. Her fragmented red blood cell concentration was 28.8%. We suspected clinical thrombotic thrombocytopenic purpura and started plasma exchange. She recovered fully after the plasma exchange and was discharged on day 31. We eventually diagnosed thrombotic microangiopathy because her ADAMTS13 activity was not reduced.ConclusionsIt is important to recognize the possibility that thrombotic microangiopathy may occur after severe trauma. In the critical care setting, unexplained thrombocytopenia and hemolytic anemia should be investigated to eliminate the possibility of thrombotic microangiopathy. Early plasma exchange may help to prevent unfortunate outcomes in patients with thrombotic microangiopathy following trauma.