Fatal pulmonary fibrosis: a post-COVID-19 autopsy case.

There is growing evidence of histopathological changes in autopsied individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); however, data on histopathological changes in autopsied patients with eradicated COVID-19 are limited. We performed an autopsy on a Caucasian female in her 80s, who died due to severe, bilateral pulmonary fibrosis after eliminated SARS-CoV-2 infection. In addition, CT scans from 2 months before infection and from 6 days prior to death were compared. Comparison of the CT scans showed bilateral development of widespread fibrosis in previously healthy lungs. Microscopic examination showed different areas with acute and organising diffuse alveolar damage and fibrosis with honeycomb-like remodelling and bronchial metaplasia. We here report a unique autopsy case with development of widespread pulmonary fibrosis in a woman in her 80s with previous COVID-19 and no history of pulmonary illnesses.

Pseudomonas aeruginosa antibody response in cystic fibrosis decreases rapidly following lung transplantation.

BACKGROUND: Specific Pseudomonas aeruginosa (PA) precipitating immunoglobulin G antibodies in serum are correlated with PA biofilm infection and are used as diagnostic and prognostic markers in cystic fibrosis (CF). The aim of this study was to examine the change of PA antibody response in CF patients after bilateral sequential lung transplantation (LTx). METHODS: PA antibodies and airway bacteriology were retrospectively evaluated in 20 chronically infected CF patients, who underwent LTx between 2001 and 2016 at Rigshospitalet, Copenhagen. Yearly precipitin counts from one year before LTx and up to five years after LTx were compared. Monthly airway cultures were examined in the five-year period after LTx. In addition, crossed immunoelectrophoresis (CIE) were analysed for each patient for antigenic similarities from time of infection, pre-LTx and post-LTx. RESULTS: All patients experienced a significant drop in PA antibodies from one year pre-LTx to one year post-LTx (p < 0.0001). The PA antibody level did not differ between those, who became reinfected immediately after LTx, and those, who did not. No patients regained the high pre-LTx precipitin levels in the following five years. The antigenic specificities of the sera post-LTx were in each patient similar to the antigenic specificities at the beginning of infection indicating a decades long memory of their immune response like an "immunological fingerprint". CONCLUSIONS: After LTx a significant and continuous reduction in PA antibodies was observed. The reduction was independent of immediate reinfection after LTx. A novel three-factor explanatory model is presented.

A systematic review of studies on the faecal microbiota in anorexia nervosa: future research may need to include microbiota from the small intestine.

PURPOSE: Anorexia nervosa (AN) is a poorly understood and often chronic condition. Deviations in the gut microbiota have been reported to influence the gut-brain axis in other disorders. Therefore, if present in AN, it may impact on symptoms and illness progression. A review of the gut microbiota studies in AN is presented. METHOD: A literature search on PubMed yielded 27 articles; 14 were selected and based on relevance, 9 articles were included. The findings were interpreted in the larger context of preclinical research and clinical observations. RESULTS: 8 out of 9 included studies analysed microbiota from faeces samples, while the last analysed a protein in plasma produced by the gut. Two studies were longitudinal and included an intervention (i.e., weight restoration), five were cross-sectional, one was a case report, and the last was a case series consisting of three cases. Deviations in abundance, diversity, and microbial composition of the faecal microbiota in AN were found. CONCLUSION: There are currently only a few studies on the gut microbiota in AN, all done on faeces samples, and not all describe the microbiota at the species level extensively. The Archaeon Methanobrevibacter smithii was increased in participants with a BMI < 25 in one study and specifically in AN patients in three studies. Methanobrevibacter smithii may, if detected, be a benchmark biomarker for future studies. We propose that microbiota samples could also be collected from the small intestine, where a major exchange of nutrients takes place and where the microbiota may have a biological impact on AN.