Point-of-Care Testing Using Invasive and Non-Invasive Hemoglobinometers: Reliable and Valid Method for Estimation of Hemoglobin among Children 6–59 Months
Authors: Ramaswamy Gomathi , Vohra Kashish , Yadav Kapil , Kaur Ravneet , Rai Tripti , Jaiswal Abhishek , Kant Shashi 
Published: November 2020

Introduction

Globally around 47.4% of children and in India, 58% of children aged 6–59 months are anemic. Diagnosis of anemia in children using accurate technologies and providing adequate treatment is essential to reduce the burden of anemia. Point-of-care testing (POCT) devices is a potential option for estimation of hemoglobin in peripheral and field settings were the hematology analyzer and laboratory services are not available.

Objectives

To access the validity of the POCTs (invasive and non-invasive devices) for estimation of hemoglobin among children aged 6–59 months compared with hematology analyzer.

Methods

The study participants were enrolled from the pediatric outpatient department in Haryana, India, from November 2019 to January 2020. Hemoglobin levels of the study participants were estimated in Sahli’s hemoglobinometer and invasive digital hemoglobinometers (DHs) using capillary blood samples. Hemoglobin levels in non-invasive DH were assessed from the finger/toe of the children. Hemoglobin levels measured in POCTs were compared against the venous blood hemoglobin estimated in the hematology analyzer.

Results

A total of 120 children were enrolled. The mean (SD) of hemoglobin (g/dl) estimated in auto-analyzer was 9.4 (1.8), Sahli’s hemoglobinometer was 9.2 (1.9), invasive DH was 9.7 (1.9), and non-invasive DH was 11.9 (1.5). Sahli’s hemoglobinometer (95.5%) and invasive DH (92.2%) had high sensitivity for the diagnosis of anemia compared with non-invasive DH (24.4%). In contrast, non-invasive DH had higher specificity (96.7%) compared with invasive DH (83.3%) and Sahli’s hemoglobinometer (70%). Invasive DH took the least time (2–3 min) for estimation of hemoglobin per participant, followed by Sahli’s (4–5 min) and non-invasive DH (5–7 min).

Conclusion

All three POCT devices used in this study are reasonable and feasible for estimating hemoglobin in under-5 children. Invasive DHs are potential POCT devices for diagnosis of anemia among under-5 children, while Sahli’s can be considered as a possible option, where trained and skilled technicians are available. Further research and development are required in non-invasive DH to improve accuracy.

Lay summary

In India, anemia is a serious public health problem, where 58% of the children aged 6–59 months are anemic. Point-of-care testing (POCT) using digital hemoglobinometers (DHs) has been recommended as one of the key interventions by the Anemia Mukt Bharat program since 2018 in India. These POCT devices are easy to use, less invasive, can be carried to field, require minimal training and results are available immediately. Therefore this study assessed the validity of POCT devices—invasive DH, non-invasive DH and Sahli’s hemoglobinometer among 6–59 months children in facility setting compared with the gold standard hematology analyzer. A total of 120 children under 6–59 months of age were enrolled from the pediatric outpatient department in Haryana, India, from November 2019 to January 2020. The (mean hemoglobin in g/dl) invasive (9.7) and non-invasive DH (11.9) overestimated hemoglobin value, while Sahli’s (9.2) underestimated hemoglobin compared with hematology analyzer (9.4). Invasive DH (92.2%) and Sahli’s hemoglobinometer (95.5%) reported high ability to correctly identify those with anemia compared with non-invasive DH (24.4%). In contrast, non-invasive DH (96.73%) had higher ability to correctly identify those without the anemia compared with invasive DH (83.3%) and Sahli’s (70%).