The chemical and laboratory investigation of hemolysis

THE IMPACT OF SCHISTOCYTE DETECTION ON MORTALITY AND ORGAN FAILURE IN PATIENTS WITH SEPSIS

ABSTRACT

Purpose : This study aimed to investigate the presence of schistocytes in patients with sepsis and its association with mortality and organ failure. Methods : We conducted a retrospective observational study at Shiga University of Medical Science Hospital, Japan, from January 2015 to April 2021. This study included patients diagnosed with sepsis or septic shock. Schistocytes were identified through daily hematological examinations. Moreover, data on mortality rates and organ failure based on Sequential Organ Failure Assessment scores were systematically collected and analyzed. Results : Schistocytes were detected in 41 of the 330 patients with sepsis. The presence of schistocytes was associated with significantly high 90-day and 1-year mortality rates (48.7% and 68.2%, respectively; P < 0.001). Patients with schistocytes exhibited higher Sequential Organ Failure Assessment scores, particularly in the coagulation and renal components, indicating more severe organ failure than that observed in patients without schistocytes. These findings persisted even after adjusting for confounding factors, such as age, sex, and baseline comorbidities. Additionally, we observed that patients with schistocytes required frequent red blood cells, further highlighting the severity of their conditions. Conclusion : Schistocytes are significantly associated with increased long-term mortality and organ failure in patients with sepsis. Their detection may provide crucial insights into disease severity, guide targeted therapeutic strategies, and potentially improve the long-term outcomes of sepsis management.

Exploring the intersection: Peptic ulcers and hemolysis-Unraveling the complex relationship

This paper investigates the intriguing relationship between peptic ulcers and hemolysis, 2 seemingly distinct medical conditions, aiming to unravel their potential interconnections and clinical implications. While traditionally studied in isolation, recent evidence has surfaced suggesting possible links and shared mechanisms between these conditions. This paper explores the underlying pathophysiological associations, shared risk factors, diagnostic challenges, management strategies, and implications for clinical practice and health policy. The interplay between peptic ulcers and hemolysis stems from shared inflammatory pathways, notably attributed to Helicobacter pylori infection in peptic ulcers, which might trigger systemic inflammatory responses contributing to hemolysis. Common risk factors including genetic predispositions, autoimmune disorders, and medication use (such as nonsteroidal anti-inflammatory drugs) are implicated in the development of both peptic ulcers and hemolytic conditions, suggesting a potential convergence of these disorders in affected individuals. Diagnostic considerations pose challenges, as overlapping symptoms and laboratory findings may complicate accurate differentiation between peptic ulcers and hemolysis. Recognizing the potential interplay between peptic ulcers and hemolysis holds significant implications for clinical practice and health policy. Streamlining diagnostic algorithms, fostering interdisciplinary collaborations, and developing tailored guidelines are pivotal in optimizing patient care. Continued research efforts, collaborative clinical approaches, and informed health policies are essential in advancing our understanding and enhancing patient care for individuals navigating the intersection of peptic ulcers and hemolysis.

Clinical Manifestations and Risk Factors Associated with 14 Deaths following Swarm Wasp Stings in a Chinese Tertiary Grade A General Hospital: A Retrospective Database Analysis Study

INTRODUCTION

The objective was to evaluate the poisoning severity score (PSS) as an early prognostic predictor in patients with wasp stings and identify associated clinical characteristics and risk factors for mortality.

METHODS

A total of 363 patients with wasp stings at Suining Central Hospital between January 2016 and December 2018 were enrolled. Within the first 24 h of admission, the poisoning severity score (PSS) and the Chinese expert consensus on standardized diagnosis and treatment of wasp stings (CECC) were utilized for severity classification, and their correlation was examined. Patients were then divided into survival and death groups based on discharge status. Logistic regression analysis was employed to analyze factors influencing patients' outcomes.

RESULTS

The mortality of wasp sting patients was 3.9%. The PSS and CECC were found to correlate for severity classification. Additionally, female gender, age, number of stings, and PSS were identified as independent risk factors for mortality in wasp sting patients. Combining these four factors yielded an AUC of 0.962 for predicting death.

CONCLUSIONS

PSS aids in early severity classification of wasp stings. Female gender, age, number of stings, and PSS were independent mortality risk factors in these patients.

Quantitative MRI evaluation of bone marrow in sickle cell disease: relationship with haemolysis and clinical severity

AIM

To evaluate bone marrow fat fraction using the Dixon technique (FFDix) of magnetic resonance imaging (MRI) as a potential biomarker of haemolysis and clinical severity in the overall assessment and follow-up of sickle cell disease (SCD) patients.

MATERIAL AND METHODS

The present study was a cross-sectional study in which healthy individuals and SCD patients (matched for age, sex, and weight) were subjected to MRI of the lumbar spine and pelvis to quantify FFDix in the bone marrow using the Dixon technique. SCD severity was analysed by clinical and laboratory data, and an online calculator. A high degree of haemolysis was defined using the cut-off values haemoglobin (Hb) ≤10 g/dl, lactate dehydrogenase (LDH) ≥325 U/l, reticulocytes ≥3% and total bilirubin (TB) ≥1.2 mg/dl. Pearson's correlation, receiver operating characteristic (ROC) curve and binary logistic regression analysis were performed.

RESULTS

Forty-eight SCD patients (26 homozygous: HbSS and 22 compound heterozygous: HbSC) and 48 healthy individuals participated in the study. FFDix was lower in SCD patients than in the control group, showing even lower values in the HbSS subtype and patients with a higher degree of haemolysis. HbSC patients with a higher degree of haemolysis using hydroxyurea (medium dosage 9.8 mg/kg/day) had lower FFDix. ROC curves and odds ratios for detecting patients with a higher degree of haemolysis at the different FFDix measurement sites demonstrated excellent performance: iliac bones (cut-off ≤16.75%, AUC = 0.824, p<0.001), femoral heads (cut-off ≤46.7%, AUC = 0.775, p=0.001), lumbar vertebrae (cut-off ≤7.8%, AUC = 0.755, p=0.002).

CONCLUSION

Decreased FFDix is indicative of higher degree of haemolysis and SCD severity with great potential as a non-invasive biomarker contributing to the overall assessment and follow-up of SCD patients.

Erythroprotective Potential of Phycobiliproteins Extracted from Porphyridium cruentum

There are multiple associations between the different blood groups (ABO and RhD) and the incidence of oxidative stress-related diseases, such as certain carcinomas and COVID-19. Bioactive compounds represent an alternative to its prevention and treatment. Phycobiliproteins (PBP) are bioactive compounds present in the microalga Porphyridium cruentum and, despite its antioxidant activity, their inhibitory effect on hemolysis has not been reported. The aim of this work was to evaluate the erythroprotective potential of phycobiliproteins from P. cruentum in different blood groups. The microalga was cultured in F/2 medium under controlled laboratory conditions. Day 10 of culture was determined as the harvest point. The microalgal biomass was lyophilized and a methanolic (MetOH), Tris HCl (T-HCl), and a physiological solution (PS) ultrasound-assisted extraction were performed. Extract pigments were quantified by spectrophotometry. The antioxidant activity of the extracts was evaluated with the ABTS+•, DPPH•, and FRAP methods, finding that the main antioxidant mechanism on the aqueous extracts was HAT (hydrogen atom transfer), while for MetOH it was SET (single electron transfer). The results of the AAPH, hypotonicity, and heat-induced hemolysis revealed a probable relationship between the different antigens (ABO and RhD) with the antihemolytic effect, highlighting the importance of bio-directed drugs.

Biomarkers and laboratory assessments for monitoring the treatment of patients with paroxysmal nocturnal hemoglobinuria: Differences between terminal and proximal complement inhibition

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, life-threatening, acquired disease in which blood cells lacking complement regulatory proteins are destroyed because of uncontrolled complement activity. Since 2007, terminal complement inhibitors have revolutionized the treatment of this disease. However, patients treated with these inhibitors can still experience anemia because of C3-mediated extravascular hemolysis and clinically relevant levels of breakthrough or residual intravascular hemolysis. Proximal complement inhibitors, which are only just beginning to emerge, have the potential to address this problem by targeting components of the pathway upstream of C5, thereby protecting patients against both intra- and extravascular hemolysis. In this review, we describe different biomarkers that can be used to monitor complement pathway blockade and discuss key laboratory assessments for evaluating treatment efficacy. We also consider how these assessments are affected by each class of inhibitor and highlight how evolving treatment goals may influence the relative importance of these assessments.

Tanshinone IIA-Loaded Micelles Functionalized with Rosmarinic Acid: A Novel Synergistic Anti-Inflammatory Strategy for Treatment of Atherosclerosis

Rosmarinic acid (RA) and tanshinone IIA (TA) which are effective components in Salvia miltiorrhiza show anti-inflammatory potential against atherosclerosis. Based on polysulfated propylene-polyethylene glycol (PPS-PEG), RA was grafted onto this polymer via amide bonds to form a micelle carrier for TA encapsulation: PPS-PEG-RA@TA. A potent inhibitory effect on lipopolysaccharide (LPS) -induced proliferation of endothelial cells with significant intracellular uptake was observed with this system. This could have been the result of release of TA in a reactive oxygen species (ROS) environment and stronger antioxidant effect of RA. The synergistic effect was optimized when the combination was used in a molar ratio of 1:1. Mechanistic studies showed that, compared with PPS-PEG-RA and TA+RA, PPS-PEG-RA@TA micelles could more effectively regulate the nuclear factor-kappa B (NF-κB) pathway to reduce expression of vascular cell adhesion molecule-1 (VCAM-1), inhibit the inflammatory cascade and reduce endothelial-cell injury. One month after intravenous injection of PPS-PEG-RA@TA micelles, the plaque area in murine aortic vessels was reduced significantly, and serious toxic side-effects were not observed in vivo, along with excellent biocompatibility. In summary, PPS-PEG-RA@TA micelles could achieve synergistic treatment of atherosclerosis.

Mechanisms of 8-aminoquinoline induced haemolytic toxicity in a G6PDd humanized mouse model

Primaquine (PQ) and Tafenoquine (TQ) are clinically important 8‐aminoquinolines (8‐AQ) used for radical cure treatment of P. vivax infection, known to target hepatic hypnozoites. 8‐AQs can trigger haemolytic anaemia in individuals with glucose‐6‐phosphate dehydrogenase deficiency (G6PDd), yet the mechanisms of haemolytic toxicity remain unknown. To address this issue, we used a humanized mouse model known to predict haemolytic toxicity responses in G6PDd human red blood cells (huRBCs). To evaluate the markers of eryptosis, huRBCs were isolated from mice 24–48 h post‐treatment and analysed for effects on phosphatidylserine (PS), intracellular reactive oxygen species (ROS) and autofluorescence. Urinalysis was performed to evaluate the occurrence of intravascular and extravascular haemolysis. Spleen and liver tissue harvested at 24 h and 5–7 days post‐treatment were stained for the presence of CD169+ macrophages, F4/80+ macrophages, Ter119+ mouse RBCs, glycophorin A+ huRBCs and murine reticulocytes (muRetics). G6PDd‐huRBCs from PQ/TQ treated mice showed increased markers for eryptosis as early as 24 h post‐treatment. This coincided with an early rise in levels of muRetics. Urinalysis revealed concurrent intravascular and extravascular haemolysis in response to PQ/TQ. Splenic CD169+ macrophages, present in all groups at day 1 post‐dosing were eliminated by days 5–7 in PQ/TQ treated mice only, while liver F4/80 macrophages and iron deposits increased. Collectively, our data suggest 8‐AQ treated G6PDd‐huRBCs have early physiological responses to treatment, including increased markers for eryptosis indicative of oxidative stress, resulting in extramedullary haematopoiesis and loss of splenic CD169+ macrophages, prompting the liver to act as the primary site of clearance.

Levels of haemolysis have no effect on femoral vein post-mortem tryptase levels

Haemolysis is reported to be an artefact that may alter post-mortem tryptase levels. However, previous studies did not sample peripheral blood using newly standardised methods. Recent studies have shown that some previously recognised peri- and post-mortem confounders can be muted by careful sample collection with first clamping and then sampling the femoral vein. This prospective study investigated the relationship between the degree of haemolysis of the blood samples and femoral vein post-mortem tryptase levels when sampled using this recommended method. Seventy consecutive post-mortem tryptase levels in non-anaphylactic deaths were compared to the degree of haemolysis of these samples, and results showed no significant correlation between them. The mean post-mortem tryptase level was 9.5 μg/L. This study demonstrated that the effects of haemolysis on femoral vein post-mortem tryptase was negligible when the blood was sampled using the recommended sampling method. Future studies on post-mortem tryptase as well as other typically used blood markers in forensics are recommended to adopt this method of blood sampling in routine practice.

[Salt sensitivity and osmotic fragility are newly specified risk factors for age-related cerebral microangiopathy]

AIM/

To assess individual values of salt sensitivity and osmotic fragility on the patient's erythrocytes and evaluate predictive ability of these parameters in the development of cerebral small vessel disease (CSVD).

MATERIAL AND METHODS

The study included 73 patients with CSVD (48 women, mean age 60.1±6.5 years) and 19 volunteers (14 women, mean age 56.9±5.4 years). Their erythrocytes were used for the measurement of salt-sensitivity by a modified salt blood test and of osmotic fragility by the classical osmotic fragility test. Binary logistic regression was used to assess the ability of salt-sensitivity and osmotic fragility to predict CSVD development. ROC analysis was used to find out the optimal threshold values of these predictors, their sensitivity and specificity.

RESULTS

An increase in salt sensitivity (cut-off: 8.5 mm/h; sensitivity 64%, specificity 74%) and osmotic fragility (cut-off: 0.62 u.a.; sensitivity 52%, specificity 90%) or their simultaneous use (p of the model <0.000001, cut-off 0.62; sensitivity 88%, specificity 68%) are the independent predictors of CSVD. An increase in salt sensitivity and osmotic fragility is also independently associated with the acceleration of severity of white matter hyperintensities according to Fazekas stages (p=0.019 and 0.004, respectively).

CONCLUSION

The possibility of prediction of CSVD according to an increase in salt sensitivity and osmotic fragility allows us to consider them as the risk factors of CSVD. The standardization of these tests for use in clinical practice is necessary to identify the risk group for CSVD and its individual prevention.

Plasma hemoglobin: A method comparison of six assays for hemoglobin and hemolysis index measurement

INTRODUCTION

Plasma hemoglobin (Hb) is measured for assessment of in vivo and in vitro hemolysis. The objective of the present investigation was to conduct a method comparison of five quantitative and one semi-quantitative Hb and H-index (hemolysis index) assays to evaluate their performance measuring plasma Hb in clinical specimens.

METHODS

One hundred and fourteen clinical specimens previously tested for plasma Hb using a laboratory-developed spectrophotometric assay were also tested for Hb using a HemoCue Plasma/Low Hb assay (azide methemoglobin), a laboratory-modified Pointe Scientific Hb assay (cyanmethemoglobin), tested for H-index measurements using a Roche cobas c501, an Abbott Architect c8000, and a semi-quantitative (binned) H-index measurement on a Beckman AU5800. The reference result was defined as the median Hb score (median of all Hb or H-index results).

RESULTS

The laboratory-developed spectrophotometric Hb assay and Roche H-index methods mostly closely matched the median Hb score across all data, as well as for lower range median Hb score results ≤2.0 g/L. Two-way frequency table analysis using an Hb (or H-index) cutoff of 0.5 g/L (or 0.5 H-index units) was then performed to compare methods to the median Hb score cutoff. The Beckman method had the highest accuracy at this cutoff, the Roche and Abbott methods had the highest positive predictive value (PPV), and the Beckman, HemoCue, and Pointe methods had the highest negative predictive value (NPV).

CONCLUSIONS

Plasma Hb and H-index results vary by method. Laboratories should evaluate the performance characteristics of their respective assays when considering adoption of spectrophotometric or chemical methods for plasma Hb assessment.

The Predictive Value of Salt Sensitivity and Osmotic Fragility in the Development of Cerebral Small Vessel Disease

Increased salt intake in food probably affects the progression of cerebral small vessel disease (CSVD), which justifies the study of disturbances in sodium homeostasis associated with the development of CSVD. We aimed to clarify the role of salt sensitivity and osmotic fragility in the development of CSVD. Erythrocyte salt sensitivity was measured using the modified salt blood test, and osmotic fragility was measured using the classic osmotic fragility test in 73 patients with CSVD (48 women; 60.1 ± 6.5 years) and 19 healthy volunteers (14 women; 56.9 ± 6.4 years). Salt sensitivity and osmotic fragility exhibited a predictive value in relation to CSVD. These parameters were associated with an increase in white matter hyperintensities (P = 0.019 and 0.004, respectively). Their simultaneous use increased their predictive ability for CSVD (P < 0.000001; AUC (95% CI), 0.824 (0.724-0.923)). The possibility of predicting CSVD using erythrocyte salt sensitivity and osmotic fragility indicates the value of the individual glycocalyx buffer capacity in relation to sodium and the activity of sodium channels in the development of CSVD. Increased salt sensitivity and osmotic fragility seem to be risk factors for CSVD.

Laboratory Approach to Hemolytic Anemia

Hemolytic anemias are a group of disorders with varied clinical and molecular heterogeneity. They are characterized by decreased levels of circulating erythrocytes in blood. The pathognomic finding is a reduced red cell life span with severe anemia or, compensated hemolysis accompanied by reticulocytosis. The diagnostic workup or laboratory approach for hemolytic anemias is based on methodical step-wise testing which includes red blood cell morphology, hematological indices with increased reticulocyte count along with clinical features of hemolytic anemias. If conventional laboratory tests are unable to detect the underlying cause of hemolysis, genetic testing is recommended. Sanger sequencing along with conventional testing is the most efficient way to diagnose the underlying genetic causes, especially in thalassemias/hemoglobinopathies, if required. However, hemolytic anemias being highly heterogeneous disorders, next-generation sequencing-based screening is rapidly becoming an efficient way to decipher the etiologies where common causes have been excluded.