Critically ill patients: histopathological evidence of thyroid dysfunction

Abstract Background: Critical illness is characterized by severe biphasic physical and metabolic stress as a result of systemic inflammatory response syndrome and multiple organ dysfunction syndrome, and is frequently associated with non-thyroidal illness. The purpose of this study is to better understand the cytomorphological basis of NTI by performing histopathological examinations of the thyroid gland on autopsies of patients who died from critical illness. Methods: Histopathological examination of the thyroid gland of 58 critically ill patients was performed in our hospital. The cases included 24 cases of burn injury, 24 cases of traumatic brain injury, and 10 cases of cerebral stroke. Thyroid samples obtained during a medicolegal autopsy were preserved in 10% formol saline and stained with hematoxylin and eosin. The sections were visualized under light microscopy. Results: Out of the 58 cases examined, 21 patients showed normal thyroid findings, and the rest of the cases had unusual thyroid findings in the histopathological study. The principal finding was the distortion of thyroid follicular architecture. Other findings include mononuclear cell infiltration, clumping of thyroglobulin, and exhaustion of thyroid follicles. Conclusion: Critical illness produces metabolically damaging effects on the thyroid gland, which functionally corresponds to the state of low T3 syndrome. These effects worsen over time and warrant intervention through hormone replacement therapy.