Correlation Between Clinical Assessment and Postmortem Lung Biopsy in Patients With Pulmonary Infiltrates and Respiratory Failure.

Background: Pulmonary complications commonly cause mortality in critically ill patients with acute and chronic liver diseases in the intensive care unit. Pneumonia is the most common clinical diagnosis supported by radiological and microbiological results, which are subjective and often with poor yield. The study aimed to correlate clinical diagnosis and postmortem lung histology in patients with liver disease with respiratory failure.

Methods: Records of acute and chronic liver disease patients with respiratory failure-associated mortality and postmortem lung biopsy from September 2009 to March 2020 were analyzed. Clinical diagnosis supported by radiological and/or microbiological data was compared with histology.

Results: One hundred eight patients (age 46.83±12.96 years), males 80 (74.1%), 63 (58.3%) cirrhosis of the liver, 30 (27.8%) acute-on-chronic-liver-failure, and 9 (8.3%) acute liver failure, were analyzed. Of the 76 patients (70.37 % of the total) with pneumonia, 33 (43.4 %) had histological evidence of pneumonia. Other histological diagnoses in these patients were normal or nonspecific changes in 27 (35.5 %) and alveolar hemorrhage in 13 (17.1 %). In the remaining 32 patients, histological diagnosis of pneumonia was evident in nine patients (28.1%). Using postmortem histology as the gold standard, the sensitivity, specificity, positive predictive value, and negative predictive value for clinical diagnosis of pneumonia were found to be 78.57%, 34.85%, 43.42%, and 71.88% respectively. The kappa statistics for agreement between the two was 0.12 (95% C.I. -0.04 to 0.27) suggesting poor agreement. Age and histological pneumonia predicted significant missed diagnosis.

Conclusion: There is poor agreement between clinical diagnosis and postmortem histology. Postmortem lung biopsy helps with the unexplained cause of death.