Laboratory hematologic features of COVID-19 associated liver injury: A systematic review

BACKGROUND

Liver injury is a common complication of infection by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. The utility of laboratory hematology data in the diagnosis and risk stratification of patients with coronavirus disease 2019 (COVID-19) has not been comprehensively examined.

AIM

To address the following. (1) Are the abnormalities in hematologic parameters seen in the general population of patients with COVID-19 also seen in those patients with associated liver injury? (2) Is liver injury in COVID-19 a sign of severe disease and does liver injury correlate with hematologic markers of severe disease? And (3) What is the quality of this evidence?

METHODS

To address these questions, a comprehensive systematic review was performed. We searched the peer reviewed medical literature using MEDLINE (PubMed interface), Web of Science, and EMBASE for cohort studies that specifically addressed liver injury and COVID-19 without limitation of date of publication or language. A quality assessment of the studies was performed using the Newcastle-Ottawa Scale.

RESULTS

Thirty-two articles were suitable for inclusion in our systematic review. These included 22 articles with a cohort of COVID-19 patients with liver injury, 5 comparing non-severe vs severe COVID-19 populations in which liver injury was addressed, and 5 other cohort studies with a focus on liver injury. White blood cell count, absolute neutrophil count, absolute lymphocyte count (ALC), and hemoglobin were the parameters most helpful in distinguishing COVID-19 with liver injury from COVID-19 without liver injury. ALC and d-dimer were identified as being potentially useful in distinguishing non-severe from severe COVID-19. Liver injury was more frequently seen in cohorts with severe disease. Most studies were of high quality (24/48, 86%) with 4/28 (14%) of moderate quality and 0 of low quality.

CONCLUSION

Our study supports the use of select hematologic parameters in diagnosis and risk stratification of liver injury in COVID-19 patients. Although of overall high quality, the current medical literature is limited by the small number of studies with high statistical power and the variable definition of COVID-19 liver injury in the literature.

Outcomes of Measurable Residual Disease in Pediatric Acute Myeloid Leukemia before and after Hematopoietic Stem Cell Transplant: Validation of Difference from Normal Flow Cytometry with Chimerism Studies and Wilms Tumor 1 Gene Expression

We enrolled 150 patients in a prospective multicenter study of children with acute myeloid leukemia undergoing hematopoietic stem cell transplantation (HSCT) to compare the detection of measurable residual disease (MRD) by a "difference from normal" flow cytometry (ΔN) approach with assessment of Wilms tumor 1 (WT1) gene expression without access to the diagnostic specimen. Prospective analysis of the specimens using this approach showed that 23% of patients screened for HSCT had detectable residual disease by ΔN (.04% to 53%). Of those patients who proceeded to transplant as being in morphologic remission, 10 had detectable disease (.04% to 14%) by ΔN. The disease-free survival of this group was 10% (0 to 35%) compared with 55% (46% to 64%, P < .001) for those without disease. The ΔN assay was validated using the post-HSCT specimen by sorting abnormal or suspicious cells to confirm recipient or donor origin by chimerism studies. All 15 patients who had confirmation of tumor detection relapsed, whereas the 2 patients with suspicious phenotype cells lacking this confirmation did not. The phenotype of the relapse specimen was then used retrospectively to assess the pre-HSCT specimen, allowing identification of additional samples with low levels of MRD involvement that were previously undetected. Quantitative assessment of WT1 gene expression was not predictive of relapse or other outcomes in either pre- or post-transplant specimens. MRD detected by ΔN was highly specific, but did not identify most relapsing patients. The application of the assay was limited by poor quality among one-third of the specimens and lack of a diagnostic phenotype for comparison.

Hematology in Africa

This review of hematology in Africa highlights areas of current practice and the immediate needs for development and clinical research. Acute hematological practice is dominated by anemia, sickle cell disease, and the need to provide a safe and rapidly available supply of blood. There is a growing need for specialist services for bleeding and coagulation, hematological malignancy, and palliative care. There are many areas of practice where straightforward measures could yield large gains in patient care. There is an urgent need for good clinical research to describe the epidemiology, natural history, and management of hematological diseases in Africa.

Improving Laboratory and Clinical Hematology Services in Resource Limited Settings

The difficulties in establishing and delivering reliable clinical hematology and laboratory services in resource-limited settings are well recognized. However, much can be achieved by better use of existing resources through a concerted quality improvement approach. The recommendations of this article are based in part upon work in the thalassemias, inherited disorders of hemoglobin that are widely prevalent in Asia, which may serve as a model that is applicable to other common, chronic disorders in resource-poor settings. Available resources are highlighted and recommendations made regarding approaches to improving services. Over the last few years, a number of low and middle-income countries, obtaining support from appropriate governmental sources, have identified and overcome difficulties and significantly improved clinical services for patients with thalassemia.

A novel method for room temperature distribution and conservation of RNA and DNA reference materials for guaranteeing performance of molecular diagnostics in onco-hematology: A GBMHM study

OBJECTIVES

Performance of methods used for molecular diagnostics must be closely controlled by regular analysis of internal quality controls. However, conditioning, shipping and long lasting storage of nucleic acid controls remain problematic. Therefore, we evaluated the minicapsule-based innovative process developed by Imagene (Evry, France) for implementing DNA and RNA controls designed for clonality assessment of lymphoproliferations and BCR-ABL1 mRNA quantification, respectively.

DESIGN & METHODS

DNA samples were extracted from 12 cell lines selected for giving specific amplifications with most BIOMED-2 PCR tubes. RNA samples were extracted from 8 cell line mixtures expressing various BCR-ABL1 transcript levels. DNA and RNA were encapsulated by Imagene and shipped at room temperature to participating laboratories. Biologists were asked to report quality data of recovered nucleic acids as well as PCR results.

RESULTS

Encapsulated nucleic acids samples were easily and efficiently recovered from minicapsules. The expected rearrangements at immunoglobulin, T-cell receptor and BCL2 loci were detected in DNA samples by all laboratories. Quality of RNA was consistent between laboratories and met the criteria requested for quantification of BCR-ABL1 transcripts. Expression levels measured by the 5 laboratories were within ±2 fold interval from the corresponding pre-encapsulation reference value. Moreover aging studies of encapsulated RNA simulating up to 100 years storage at room temperature show no bias in quantitative outcome.

CONCLUSIONS

Therefore, Imagene minicapsules are suitable for storage and distribution at room temperature of genetic material designed for proficiency control of molecular diagnostic methods based on end point or real-time quantitative PCR.

A case of EDTA-dependent pseudothrombocytopenia: simple recognition of an underdiagnosed and misleading phenomenon

Background

EDTA-dependent pseudothrombocytopenia (EDTA-PTCP) is a common laboratory phenomenon with a prevalence ranging from 0.1-2% in hospitalized patients to 15-17% in outpatients evaluated for isolated thrombocytopenia. Despite its harmlessness, EDTA-PTCP frequently leads to time-consuming, costly and even invasive diagnostic investigations. EDTA-PTCP is often overlooked because blood smears are not evaluated visually in routine practice and histograms as well as warning flags of hematology analyzers are not interpreted correctly. Nonetheless, EDTA-PTCP may be diagnosed easily even by general practitioners without any experiences in blood film examinations. This is the first report illustrating the typical patterns of a platelet (PLT) and white blood cell (WBC) histograms of hematology analyzers.

Case presentation

A 37-year-old female patient of Caucasian origin was referred with suspected acute leukemia and the crew of the emergency unit arranged extensive investigations for work-up. However, examination of EDTA blood sample revealed atypical lymphocytes and an isolated thrombocytopenia together with typical patterns of WBC and PLT histograms: a serrated curve of the platelet histogram and a peculiar peak on the left side of the WBC histogram. EDTA-PTCP was confirmed by a normal platelet count when examining citrated blood.

Conclusion

Awareness of typical PLT and WBC patterns may alert to the presence of EDTA-PTCP in routine laboratory practice helping to avoid unnecessary investigations and over-treatment.