A study of spectrum of pulmonary pathology and expression of thyroid transcription factor-1 during neonatal period

ABSTRACT

Context Neonatal period is the single most hazardous period of life. The major causes of neonatal death are prematurity and respiratory distress syndrome. We report a series of neonatal autopsies in our Neonatal Intensive Care Unit with special emphasis on pulmonary pathology. The spectrum of pathological changes in the lungs and thyroid transcription factor-1 (TTF-1) expression was studied in detail with reference to its spatial distribution. Aims: This study aims to analyze the causes of neonatal death with special attention to pulmonary pathology along with associated histopathological changes in lungs. We also evaluated the expression of TTF-1 at different levels of the airway. Materials and Methods: After taking consent and anthropometric measurements, autopsy was performed. Weights of all organs were taken, and histological sections were examined under hematoxylin and eosin stain. TTF-1 immunostaining was done on lung sections. Localization of TTF-1 was evaluated at the intrapulmonary level of terminal bronchioles (TBs), distal bronchioles, and alveoli. Results: We performed a series of 25 autopsies in neonates. In our series, most of the neonates were preterm (64%), had low birth weight (44%), and died within the first 7 days of life (80%). Majority (60%) of the neonates died due to pulmonary causes, followed by septicemia (24%), congenital anomalies (12%), and birth injury (4%). Among the respiratory causes, hyaline membrane disease (HMD) was diagnosed in maximum number of cases (32%), followed by pneumonia (12%) and pulmonary hemorrhage (12%). The TTF-1 expression in TBs, distal airways, and alveoli was significantly reduced or absent in cases of HMD compared to the control group. Conclusions: In this study, we observed that HMD is the most common cause of perinatal death among respiratory disorders, and in this disease, the expression of TTF-1 is significantly reduced in TBs, distal airways, and alveoli compared to the control group.