Performance of a cost‐effective and automated blood counting system for resource‐limited settings operated by trained and untrained users

Abstract

Current flow-based blood counting devices require expensive and centralized medical infrastructure and are not appropriate for field use. In this article we report a streamlined, easy-to-use method to count red blood cells (RBC), white blood cells (WBC), platelets (PLT) and 3-part WBC differential through a cost-effective and automated image-based blood counting system. The approach consists of using a compact, custom-built microscope with large field-of-view to record bright-field and fluorescence images of samples that are diluted with a single, stable reagent mixture and counted using automatic algorithms. Sample collection utilizes volume-controlled capillary tubes, which are then dropped into a premixed, shelf-stable solution to stain and dilute in a single step. Sample measurement and analysis are fully automated, requiring no input from the user. Cost of the system is minimized through the use of custom-designed motorized components. We compare the performance of our system, as operated by trained and untrained users, to the clinical gold standard on 120 adult blood samples, demonstrating agreement within Clinical Laboratory Improvement Amendments guidelines, with no statistical difference in performance among different operator groups. The system's cost-effectiveness, automation and performance indicate that it can be successfully translated for use in low-resource settings where central hematology laboratories are not accessible.

Large field-of-view phase and fluorescence mesoscope with microscopic resolution

“…Recent studies have demonstrated the potential of bimodal imaging techniques for the diagnosis of meningitis from counting blood cells in cerebrospinal fluid 40 or from counting red blood cells (RBCs), white blood cells (WBCs), or platelets in whole blood. 41 To demonstrate the high-throughput performances of the system, we performed WBC counting in whole blood samples. In healthy blood, the ratio of WBC to RBC is roughly 0.1%.…”

Complete Blood Count as point of care testing QBC STAR™: Preliminary evaluation

“…The laboratory personnel, in particular, is primarily responsible for verifying the accuracy of test results obtained with POCT systems, 7 especially in a vast array of emergency/urgent conditions, where analytical errors (eg, both false positive and false negative test results) may cause detrimental consequences on patient's health and safety 2,7 8‐18 . It is hence essential that accurate functioning of these devices is regularly monitored, especially their alignment with conventional laboratory hematological instrumentation for the most used parameters such as hemoglobin (HB), white blood cell count (WBC), red blood cell count (RBC), mean corpuscular hemoglobin concentration (MCHC), and platelet count (PLT) 8‐18 …”

A rapid white blood cell classification system based on multimode imaging technology

“…In recent years, "point-of-care testing" (POCT) equipment has been widely used in the field of medical testing because of its advantages of being portable, easy to operate, timely and accurate [7][8][9][10][11]. In the draft of the "POCT Evidence Document", the National Academy of Clinical Biochemistry (NACB) defines POCT as "a clinical person or patient who is not trained in clinical laboratory science (self-monitoring, testing) the inspection carried out."…”

“…In recent years, “point‐of‐care testing” (POCT) equipment has been widely used in the field of medical testing because of its advantages of being portable, easy to operate, timely and accurate [7–11]. In the draft of the “POCT Evidence Document”, the National Academy of Clinical Biochemistry (NACB) defines POCT as “a clinical person or patient who is not trained in clinical laboratory science (self‐monitoring, testing) the inspection carried out.” [12] POCT equipment can be used for rapid detection of hospital bedside samples, routine clinical tests for primary care, the disaster site or the battle site and a large number of occasions where the wounded and the sick need to be diagnosed quickly [13].…”