Laboratory Assessment of Thyroid Function: Integrated Diagnostic Pathways for Laboratory Technicians and Endocrinology Specialists
Abstract
Background: Thyroid hormones regulate metabolism, cardiovascular function, and neuropsychiatric health. Even minor deviations in thyroid status can lead to multisystem disorders, making thyroid function tests (TFTs) essential in clinical practice.
Aim: To outline integrated diagnostic pathways for thyroid function assessment, emphasizing laboratory procedures, interpretive frameworks, and quality control for accurate diagnosis and monitoring.
Methods: A comprehensive review of thyroid physiology, etiologic categories, epidemiologic drivers, and laboratory methodologies was conducted. The article details specimen handling, immunoassay principles, interference factors, and quality management systems to ensure reliable TFT results.
Results: TSH remains the primary screening marker due to its sensitivity, but FT4 and FT3 measurements are critical in subclinical disease, central hypothyroidism, and treatment monitoring. Interfering factors—such as heterophile antibodies, binding protein abnormalities, and medications—can distort results, necessitating confirmatory strategies like equilibrium dialysis or mass spectrometry. Quality assurance through internal/external QC and patient-based monitoring minimizes analytical errors. Clinical interpretation must integrate physiologic context, comorbidities, and exposure history to avoid misdiagnosis.
Conclusion: Accurate thyroid diagnostics require a multidisciplinary approach combining physiologic insight, rigorous laboratory practice, and contextual interpretation. Understanding assay limitations and interference mechanisms is vital for preventing diagnostic errors and optimizing patient care.
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References
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Copyright (c) 2025 Abdullah Mohammed Almarshud, Badour Mayof Alanazi, Norah Saad Almutairi, Mehad Abdulkreem Abdulhameed Alkhifi, Marwah Ahmed Muqtiri, Hashim Saad Aldukhayni, Amal Ali Soliman Gahtani, Nasser Najem Alothman, Abdullah Al-Ghamdi, Amin Ibrahim Ahmed Otaif, Mohammed Aqeel Mohammed Alsharari
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