Journal of Paediatric Medicine & Surgery
Open Access

Pediatric laboratory medicine; Reference ranges; Neonatal screening; Clinical chemistry; Hematology; Pediatric biomarkers; Laboratory diagnostics; Point-of-care testing; Molecular diagnostics; Pediatric quality assurance

Introduction

Laboratory diagnostics form the cornerstone of pediatric care, guiding clinical decisions from the neonatal period through adolescence. Unlike adult testing, pediatric laboratory medicine requires consideration of developmental physiology, age-specific reference intervals, and minimal blood volume collection [1]. The field has evolved significantly with the incorporation of advanced automation, molecular biology, and personalized medicine. In addition to diagnosing disease, laboratories are now pivotal in screening programs, epidemiologic surveillance, and therapeutic monitoring [2].

Description

Neonatal screening is a primary area where laboratory medicine has significantly impacted public health. Conditions like congenital hypothyroidism, phenylketonuria (PKU), galactosemia, and sickle cell disease can be detected early using dried blood spot (DBS) tests, enabling timely intervention and prevention of long-term complications [3]. Pediatric clinical chemistry includes assessment of liver function, renal function, electrolyte balance, and metabolic markers. These parameters vary with age, sex, and developmental stage, necessitating age-specific reference intervals. Misinterpretation due to adult reference values can lead to diagnostic errors [4].

In hematology, complete blood counts (CBC), peripheral blood smears, and coagulation profiles help evaluate anemia, infections, leukemia, and bleeding disorders. Special consideration is given to normal variations in hemoglobin levels, white blood cell counts, and platelet indices across age groups [5]. Microbiological testing, including cultures, antigen detection, and PCR, is essential in identifying infectious agents in conditions such as meningitis, sepsis, and gastroenteritis. Rapid tests for RSV, influenza, and group A Streptococcus are widely used in pediatric settings to guide early treatment [6].

Immunological assays help diagnose autoimmune diseases, immunodeficiencies, and allergies. Measurement of immunoglobulin levels, complement components, and specific antibody titers aids in the evaluation of recurrent infections or vaccine responses [7]. Molecular diagnostics have revolutionized pediatric care through applications in infectious disease, inherited disorders, and oncology. Techniques such as PCR, next-generation sequencing (NGS), and chromosomal microarray are now part of the standard workup for genetic syndromes, metabolic errors, and pediatric cancers [8].

Results

The expansion of newborn screening programs has dramatically reduced morbidity from inborn errors of metabolism and endocrine disorders. For instance, early detection of congenital hypothyroidism via TSH measurement has nearly eradicated cretinism in developed countries [9]. Point-of-care testing (POCT) for glucose and blood gases has improved outcomes in critically ill neonates and children by enabling immediate intervention. Recent multicenter studies have validated pediatric-specific reference intervals using direct sampling methods, improving diagnostic accuracy and reducing misdiagnoses. Furthermore, the integration of electronic health records (EHRs) with laboratory information systems (LIS) has enhanced result interpretation, test utilization, and patient safety [10].

Discussion

Pediatric laboratory medicine faces unique challenges, including limited sample volume, difficulties in venipuncture, and the dynamic physiological changes from birth through adolescence. Laboratories must ensure accurate sampling, efficient testing, and appropriate interpretation to avoid unnecessary interventions or delays in care [1]. There is a growing emphasis on test stewardship—ensuring the right test is ordered at the right time. Misuse of laboratory tests in pediatrics can lead to false positives, unnecessary imaging, or hospitalizations. Clinical decision support systems integrated into LIS can help clinicians order tests based on age-specific algorithms [2].

The field is also embracing innovations like biosensors, wearable devices, and non-invasive sampling (e.g., saliva, urine, breath) to improve diagnostic access, particularly in rural or resource-limited settings. The use of dried blood spots beyond neonatal screening, including for drug monitoring and antibody surveillance, is gaining traction [4]. Quality assurance programs, staff training, and validation of pediatric assays are critical to ensuring the reliability of test results. Laboratories must also maintain compliance with accreditation standards such as ISO 15189 and CLIA regulations specific to pediatric testing.

Conclusion

Pediatric laboratory medicine is integral to modern child healthcare, providing timely and precise data that inform diagnosis, management, and prevention strategies. With ongoing advancements in analytical techniques, molecular diagnostics, and automation, laboratories are increasingly becoming partners in pediatric precision medicine. Ensuring age-appropriate reference standards, proper test utilization, and quality assurance will be essential to further enhancing pediatric patient outcomes.