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Leukocyte adhesiveness/aggregation test (LAAT) to discriminate between viral and bacterial infections in children
J Urbach1, Y Lebenthal, S Levy
1Department of Pediatrics, Shaare Zedek Medical Center, Hebrew University, Medical School, Jerusalem: Israel.
Insights
A new slide test accurately differentiates bacterial from viral infections in children by measuring white blood cell (WBC) adhesiveness. This leukocyte adhesiveness/aggregation slide test (LAAT) offers a reliable and rapid diagnostic tool for pediatricians managing febrile illnesses.
Area of Science:
- Pediatrics
- Infectious Diseases
- Hematology
Background:
- White blood cells (WBCs) exhibit increased adhesive properties during bacterial infections.
- Differentiating between viral and bacterial infections is a common diagnostic challenge in pediatric care.
- Existing acute phase reactants may lack sufficient accuracy for definitive diagnosis.
Purpose of the Study:
- To investigate the potential of differing WBC adhesive properties for distinguishing viral from bacterial infections in children.
- To evaluate the diagnostic performance of a leukocyte adhesiveness/aggregation slide test (LAAT) compared to traditional markers.
Main Methods:
- A leukocyte adhesiveness/aggregation slide test (LAAT) was performed on peripheral blood samples.
- WBC adhesiveness was assessed in children with documented bacterial infections, documented viral infections, and probable viral infections.
- LAAT results were compared with white blood cell count, differential count, and erythrocyte sedimentation rate (ESR).
Main Results:
- The LAAT demonstrated high sensitivity (92%), specificity (96%), and positive predictive value (92%).
- These performance metrics significantly outperformed those of WBC count, differential count, and ESR.
- The LAAT proved superior to other acute phase reactants in differentiating infection types.
Conclusions:
- Increased leukocyte adhesiveness/aggregation in peripheral blood can reliably indicate bacterial infections in children.
- The LAAT is a sensitive, specific, rapid, and cost-effective laboratory tool.
- The LAAT can aid pediatricians in diagnosing and managing acute febrile illnesses in children.
Objectives:
We previously noted that white blood cells (WBC) have increased adhesive properties during bacterial infections. Here, we aim to explore the possibility of using the different adhesive properties of WBC as a means of differentiating between viral and bacterial infections, a common problem in paediatrics.
Methods:
The adhesive properties of WBC in the peripheral blood of 25 children with documented bacterial infections, 15 with documented viral infections and 36 with probable viral infections, were studied by means of a leukocyte adhesiveness/aggregation slide test (LAAT). The results of the LAAT were compared with those of the other acute phase reactants, namely WBC, differential count and erythrocyte sedimentation rate (ESR), which were taken in the same blood sample in each patient.
Results:
The sensitivity, specificity and positive predictive value were 92%, 96%, and 92%, respectively for the LAAT; 83%, 87% and 80% for the ESR; 56%, 78% and 56% for the white blood cell count; and 54%, 74% and 50% for the differential count.
Conclusions:
The presence of bacterial infections in children can be tested using a simple slide test to reveal the increased state of leukocyte adhesiveness/aggregation in the peripheral blood. The LAAT is a reliable, rapid and inexpensive test, and it can be a useful laboratory tool for the paediatrician treating a child with acute febrile illness.
