The Differences in Mentzer Index between Cyanotic and Acyanotic Congenital Heart Diseases Santa Ulina*, Rizky Adriansyah, Ayodhia Pitaloka Pasaribu * dr.santa.marpaung@gmail.com Department of Child Health, Faculty of Medicine, University of Sumatera Utara, Medan, Indonesia Jl. Dr. Mansyur No.5 Padang Bulan, Medan Baru, Medan, North Sumatera, Indonesia Abstract The prevalence of congenital heart diseases (CHDs) was estimated to be 8-12 per 1000 live births. Around 77.8% and 87.2% of cyanotic and asyanotic CHD cases experienced decrease in iron levels in the blood respectively. Anemia in children with CHDs, especially with cyanosis and high hematocrit levels due to chronic hypoxia, were often underdiagnosed. The Mentzer index as a diagnostic tool for anemia was used to diagnose iron deficiency in children with cyanotic and acyanotic CHDs. This research was a cross-sectional study done in Haji Adam Malik hospital by using data from medical records. Among 110 samples, TOF and VSD were diagnosed the most in cyanotic and acyanotic CHDs respectively in children aged 1 – 5 years old. Hematological parameters such as hemoglobin, hematocrit and erythrocyte showed significant value (p<0.05) statistically. The difference of the Mentzer index with Mann-Whitney test showed significant difference (p<0.05) with median value of 12.0±3.9 and 17.2 ±4.2 in cyanotic and acyanotic CHD respectively. Published by IJRP.ORG. Selection and/or peer-review under responsibility of International Journal of Research Publications (IJRP.ORG) Keywords: Mentzer index; iron deficiency; congenital heart disease 1. Introduction Congenital heart diseases (CHDs) are the most common congenital disorder found. The prevalence of CHDs was estimated to be 8-12 cases per 1000 live births (Susan et al., 2019). Children with CHDs often suffer from iron deficiency anemia, which was caused by multiple factors. In 114 children with CHDs, 85% needed iron supplementation (Maloku-Ceku and Berisha, 2010). The prevalence of children with iron deficiency anemia in Indonesia remains high. From the data by Basic Health Research (Riskesdas) Indonesia, the prevalence of anemia in North Sumatra in year 2007 was 16.5%. While in 2013, almost 30% children aged 1 – 14 years old suffered from anemia (Depkes RI, 2007; Depkes RI, 2013). Both cyanotic and acyanotic congenital heart diseases have risks of iron reserves depletion in the body. The study by Mukherjee et al., (2018) showed 5 to 10 patients with cyanotic CHDs suffered from iron deficiency (Mukherjee et al., 2018). Meanwhile, Binh et al., (2018) reported 77.8% and 87.2% cyanotic and acyanotic CHD patients respectively suffered from the decrease in iron levels in the blood. Hemoglobin (Hb) concentration within normal range may imply that cyanotic CHD patients were relative anemia. This condition may have negative effects to mortality and morbidity (Binh et al., 2018). Soni et al., (2018) compared normal population as the control group to cyanotic CHD cases and reported 56.7% cases of iron deficiency (Soni et al., 2018). From the existing research, iron deficiency in congenital heart diseases needed to be enforced by serum ferritin, serum iron (SI), and total iron binding capacity (TIBC) level checks (Mukherjee et al., 2018). Those examinations, however, require special equipment, specialists in hematology, and high in cost. Anemia in children with CHDs, especially cyanotic children who showed high haematocrit levels due to chronic hypoxia, were often under diagnosed. Therefore, there is a need of screening tools that can be easily applied in everyday life, even when no haematologists are available, for early detection with affordable price. In some literature, the Mentzer index (MI) was used as an early screening tool to differentiate iron deficiency anemia from thalassemia (Alam et al., 2014, Djer and Madiyono, 2016, Martínez‐Quintan and Rodríguez‐González, 2013, Okoromah et al., 2011). The Mentzer index (MI) is one of the discrimination index formulas developed as a thalassemia trait test to distinguish thalassemia with other hypochromic microcytic anemia, especially iron deficiency anemia. The calculation is done by dividing the average cell volumes or mean corpuscular volume (MCV) with total 1 www.ijrp.org IJRP 2021, 77(1), 1-8; doi:.10.47119/IJRP100771520211928