Rapid Detection of Plasmodium vivax by the Hematology Analyzer for Population Screening.

In India, where malaria is endemic, the prompt and accurate detection of infections is crucial for disease management and vector control. Our study aimed to evaluate the "iRBC" flag, a novel parameter developed for routine hematology analyzers, for its sensitivity and specificity in detecting Plasmodium vivax (P. vivax) infections. We used residual blood samples from patients with suspected malaria and compared the iRBC flag results with microscopy, which serves as the gold standard. Additionally, we compared the results with rapid immuno-chromatographic tests (RDTs) commonly used in the field. Our study included 575 samples, of which 187 were positive for P. vivax. The iRBC flag demonstrated a high sensitivity of 88.7% and 86.1% on the XN and XN-L hematology analyzers, respectively, and a clinical specificity of 100% on both analyzers. Furthermore, the scattergram derived from each positive dataset exhibited distinct patterns, which facilitated rapid confirmation by laboratory specialists. Notably, the iRBC flag remained effective even in the presence of interfering conditions. Overall, our results indicate that the iRBC flag is a reliable and rapid screening tool for identifying P. vivax in routine blood testing. Our findings have significant implications for malaria detection and control in endemic regions like India.

Performance Evaluation of Fully Automated 5-Part Differential Hematology Analyzer ELite 580 (ERBA).

The ELite 580 (Erba Lachema) Hematology Analyzer is a newly developed automated hematology analyzer that uses impedance and flow cytometry technologies. The analyzer provides 25 reportable parameters including a 5-part differential and additionally 4 research parameters with a throughput of 80 samples per hour. To evaluate the performance of the fully automated 5-part differential hematology analyzer ELite 580 as per the international standards and correlate the results with a reference analyser, LH 780 from Beckman Coulter. We evaluated the analyzer's performance by determining background noise, carryover, precision, linearity and correlation of complete blood cell count parameters between the ELite 580 from Erba Lachema and the LH 780 from Beckman Coulter at a tertiary care hospital, according to the Clinical and Laboratory Standards Institute guidelines. The ELite 580 showed minimal background noise and carryover, high precision, accuracy and linearity over a wide analytical range for white blood cells, hemoglobin, red blood cells, hematocrit, and platelet parameters. Correlation between the ELite 580 and the LH 780 was good for all parameters (R2 > 0.90) except for mean corpuscular hemoglobin concentration (MCHC) and the basophil count. ELite 580 Hematology Analyzer with its precise and accurate results and ease of operation is suitable for clinical use in medium to large sized hematology laboratories. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12288-021-01423-y.

Immune Modulation and Cytomegalovirus Reactivation in Sepsis-induced Immunosuppression: A Pilot Study.

INTRODUCTION: Sepsis is a life-threatening condition caused due to dysregulated immune response to an infection and progressive immunosuppression. Reactivation of cytomegalovirus (CMV) occurs frequently in sepsis and is found associated with adverse outcomes. The study objective was to evaluate the association between incidence of CMV reactivation and immune alteration in sepsis-induced immunosuppression in patients with prolonged sepsis. PATIENTS AND METHODS: Patients admitted to intensive care unit (ICU), with severe sepsis and CMV immunoglobulin G (IgG) seropositivity, were prospectively enrolled. Other manifest immune suppression causes were excluded. Samples were collected on enrolment and further once a week until day 21 or death/discharge. CMV viral load was quantified using qPCR. Lymphocyte subset analysis (CD3+, CD4+, CD8+, CD19+, CD16+/CD56+, and CD25+CD127- regulatory T cells), human leukocyte antigen-DR isotype (HLA-DR) expression on monocytes, programmed death-1 (PD-1) expression on T lymphocytes, and proinflammatory (interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ)), anti-inflammatory cytokines levels (IL-2, IL-4, and IL-10) were analyzed by flow cytometry as markers for immunosuppression. RESULTS: A total of 25 CMV IgG-positive patients and 11 healthy controls were included. CMV reactivation occurred in 20 patients. Patients with CMV reactivation had T-cell lymphopenia. PD-1 expression on CD4+ and CD8+ T cells was markedly elevated (p <0.02) in CMV-reactivated patients compared to nonreactivated patients. HLA-DR expression was significantly low on monocytes in all septic patients (p <0.01) compared to healthy controls. IL-6 levels showed elevation at day 7, whereas IL-10 was found to be significantly higher from day 0 in CMV-reactivated group. CONCLUSION: Our study concluded that immune suppression markers and cytokine levels in patients with severe sepsis were found to be significantly associated with the incidence of CMV reactivation. HOW TO CITE THIS ARTICLE: Lambe G, Mansukhani D, Khodaiji S, Shetty A, Rodrigues C, Kapadia F. Immune Modulation and Cytomegalovirus Reactivation in Sepsis-induced Immunosuppression: A Pilot Study. Indian J Crit Care Med 2022;26(1):53-61.

Unusual immunophenotype of T-cell large granular lymphocytic leukemia: report of two cases.

Large granular lymphocytes (LGL) leukemias are commonly of the T-cell or NK-cell type. T-cell LGL leukemia is typically a disorder of mature CD3, CD8 and T-cell receptor TCR (TCR - T cell receptor)-αß positive cytotoxic T-cells. Rare variants include TCRγδ+ variants and CD4 + TCRαß+ cases. We report a case of each of these rare variants. An 83-year-old female presented with anemia and lymphocytosis with LGLs on peripheral smear. Six-color multiparametric flowcytometric analysis showed expression of CD3, heterogeneous CD7, dim CD2 and TCRγδ and lacked expression of CD5, TCRαß, CD56, CD4 and CD8. A final diagnosis of TCRγδ+ T-cell LGL leukemia was made. Differentiation between TCRγδ+ T-cell LGL leukemia and other γδ+ T-cell malignancies is of utmost importance due to the indolent nature of the former as compared to the highly aggressive behavior of the latter. An 85-year-old male diagnosed with liposarcoma was identified to have lymphocytosis during preoperative evaluation. Peripheral smear showed presence of LGLs. Flowcytometric immunophenotyping showed expression of TCRαß, CD3, CD2, CD5, CD4, dim CD8, CD56 with aberrant loss of CD7 expression. Vß repertoire analysis by flowcytometry showed 97% cells with Vß14 clonality. A final diagnosis of TCRαß+ CD4 + T-cell LGL leukemia was made. CD4 + T-cell large granular lymphocytic leukemias have an indolent, less aggressive course when compared to their CD8 + counterparts and are not necessarily associated with cytopenias. However, their association with secondary neoplasia (29% of the cases) warrants a high degree of suspicion in the diagnosis as also noted in the index case. Use of a wide panel of antibodies and newer modalities such as Vß repertoire analysis helps in accurate subtyping of LGL leukemia.