Author: Tri Ratnaningsih, Galih R Martani, Dhia C Putri, Usi Sukorini
Schistocytes Evaluation in Iron Deficiency: An Assessment Adopted From ICSH Nomenclature Guideline
Abstract
Backgorund
The diagnostic validity of schistocyte count in diagnosing iron deficiency in the microcytic population is critical to evaluate. The purpose of this study is to identify the correlation between schistocyte count and iron parameters, and the performance of schistocyte count in diagnosing iron deficiency in the microcytic population.
Method
A cross-sectional observational study with a population consisting of general check-up participants. Participants underwent complete blood tests using ADVIA 2120i® (Siemens, Tarrytown, NY, USA). Subjects were excluded if they were pregnant. Serum ferritin was examined in subjects with Mean Corpuscular Value (MCV) < 80 fL using Cobas 6000® analyzer series (Roche Diagnostics Corporation, Indianapolis, USA). The relationship between variables was determined using the Spearman correlation test. The schistocyte count was further compared to the Ferritin level using Receiver Operating Characteristic (ROC) curve to diagnose iron deficiency. Data analysis used in this study was Statistical Package for the Social Sciences (SPSS) (version 25; IBM Corporation, Armonk, New York, USA). The normality test for hematology parameter, RBC fragment, and iron status was the Kolmogorov-Smirnov test, followed by the mean difference test using the Mann-Whitney U test due to abnormal data distribution.
Result
Out of 805 general check-up participants, 65 subjects consisting of 17 males and 48 females aged 18–56 years had Mean Corpuscular Value (MCV) < 80 fL. Serum ferritin examination showed 25 patients with iron deficiency and the other 40 subjects without iron deficiency. There was a significant difference in the schistocyte count between the two groups (p < 0,001). Correlation analysis obtained a significant relationship between schistocyte count and serum ferritin (r=-0,67, p < 0,001). The Receiver Operating Characteristic (ROC) curve analysis provided Area Under the Curve (AUC) of schistocyte count is 0.827 with Youden Index (YI) 55% for a cut-off of ≥0.75%.
Conclusion
Schistocyte count has a significant correlation with iron parameters and can be used as a marker for iron deficiency in the microcytic population. Health facilities that do not have access to iron parameters examination can perform a schistocyte count.
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Author: Elsa Murhandarwati, Elizabeth Henny Herningtyas, Puspawati Puspawati, Fridolina Mau, Shen-Bo Chen, Hai-Mo Shen, Jun-Hu Chen
Genetic diversity of Merozoite surface protein 1–42 (MSP1-42) fragment of Plasmodium vivax from Indonesian isolates: Rationale implementation of candidate MSP1 vaccine
Abstract
Backgorund
Morbidity and mortality related to malaria in Indonesia are attributed to both Plasmodium falciparum and P. vivax parasites. In addition to vaccines for P. falciparum, vaccines against P. vivax are urgently needed for the prevention of the disease. An extensively studied antigen is the carboxyl-terminus of the 42 kDa region of P. vivax merozoite surface protein-1 (PvMSP1-42). The design of a vaccine based on this antigen requires an understanding of the extent of polymorphism. However, there is no information on the genetic diversity of the antigen in Indonesia. This study aimed to profile the diversity of PvMSP1-42 and its two subdomains (PvMSP1-33 and PvMSP1-19) among Indonesian P. vivax isolates.
Method
A total of 52 P. vivax-infected blood samples were collected from patients in two different endemic areas in Indonesia: Banjarmasin (Kalimantan) and Sumba Timur (Nusa Tenggara Timur). The polymorphic characteristics and natural selection of PvMSP1-42 were analyzed using the DnaSP, MEGA, and Structure software.
Result
Thirty distinct haplotypes of PvMSP1-42 were identified. They displayed amino acid changes compared to the reference PVP01 sequence. Most of the mutations were concentrated in the 33 kDa fragment. PvMSP1-42 of the Indonesian isolates appeared to be under positive selection. Recombination may also play a role in the resulting genetic diversity of PvMSP1.
Conclusion
In conclusion, PvMSP1-42 of Indonesian isolates displayed allelic polymorphisms caused by mutation, recombination, and positive selection. These results will aid the understanding of the P. vivax population in Indonesia and to develop a PvMSP1 based vaccine against P. vivax.