Thrombotic microangiopathy with kidney involvement in a patient with coronavirus disease 2019: A case report and literature review (preprint)

Background and aim: Millions of people worldwide have suffered from coronavirus disease 2019 (COVID-19). COVID-19 can lead to coagulopathy and thrombosis, presenting as pulmonary artery thromboembolism, deep vein thrombosis, and thrombotic microangiopathy (TMA), the latter being a rare finding in affected patients’ kidneys. Prior reports have rarely addressed the pathophysiology, clinical presentations, and therapeutic options in patients with COVID-19-associated TMA. Case presentation: We herein described a case of renal biopsy-proven TMA after COVID-19 in a 36-year-old woman. Initial examination revealed inflammation, acute kidney injury (AKI), anemia, and thrombocytopenia. She was diagnosed with hemolytic uremic syndrome, pulmonary infection, and COVID-19. After treatment, her condition stabilized but remained hemodialysis-dependent after discharge. One week later, she was re-hospitalized, and physical examination showed anemia and bilateral lower extremity edema. Abdominal ultrasound showed increased bilateral kidney echogenicity. Whole-exome sequencing detected an unknown variant of the C3 gene associated with hemolytic uremic syndrome susceptibility type 5/complement C3 deficiency. Kidney biopsy showed renal artery lesions, including small arteriole endothelial swelling, intimal thickening, mucinous degeneration, luminal occlusion, and small arterial wall necrosis. She received plasma exchange and steroids with significant renal function recovery. Conclusion: TMA likely contributed to AKI after COVID-19,thus supporting the notion that TMA plays an important role in the pathogenesis of COVID-19-related kidney injury. When diagnosing and treating COVID-19 patients with abnormal renal function, clinicians should incorporate kidney biopsy and genetic testing for the complement system, identify renal-limited and systemic TMA, and treat accordingly, which can improve patient outcomes.

Telemedicine and intraductal papillary mucinous neoplasms: Analysis of a new follow-up strategy during COVID-19 outbreak.

BACKGROUND: The Coronavirus pandemic outbreak in 2019 and the saturation of healthcare system led to an increased use of digital tools for surveillance. In this study we described our experience using telemedicine to follow-up on patients with intraductal papillary mucinous neoplasms during the COVID-19 era and analyze those factors associated to patients' satisfaction. METHODS: This 1-year retrospective observational study enrolled patients with intraductal papillary mucinous neoplasms followed-up by telemedicine during COVID-19 outbreak. Patients with high-risk features needing on-site physical examination or declining remote follow-up were excluded. A 13-question survey was conducted; demographic, geographic, and employment information was collected. Univariate and multivariate analyses were performed to evaluate those factors associated to patients' satisfaction. RESULTS: Out of 287, a total of 177 patients with intraductal papillary mucinous neoplasms were included: the mean age was 69 (44-87) years and the male/female ratio was 0.78. A total of 80 (45.2%) patients had previously experienced abdominal pain. Most patients (85.3%) were satisfied with telemedicine: at univariate analysis, age ≥70 years (P = .007), retirement (P = .001), and absence of previous abdominal pain (P = .05) were significantly associated with patient satisfaction. At multivariate analysis, the absence of previous abdominal pain was the only factor independently associated with patient satisfaction (odds ratio 5.964, 95% confidence interval 2.21-16.11, P < .001). CONCLUSION: Telemedicine allows a new follow-up strategy that can be used in selected patients with intraductal papillary mucinous neoplasms. The absence of previous abdominal pain is associated with patient satisfaction during follow-up. Further studies are needed to evaluate safety of remote follow-up in patients with intraductal papillary mucinous neoplasms.

The UIP honeycomb airway cells are the site of mucin biogenesis with deranged cilia (preprint)

Honeycombing (HC) is a histological pattern consistent with Usual Interstitial Pneumonia (UIP). HC refers to cystic airways (HC airways) located at sites of dense fibrosis with marked mucus accumulation. Utilizing laser capture microdissection coupled mass spectrometry (LCM-MS), we interrogated the fibrotic HC airway cells and fibrotic uninvolved airway cells (distant from sites of UIP and morphologically intact) in 10 UIP specimens; 6 non-fibrotic airway cell specimens served as controls. Furthermore, we performed LCM-MS on the mucus plugs found in 6 UIP and 6 mucinous adenocarcinoma (MA) specimens. The mass spectrometry data were subject to both qualitative and quantitative analysis and validated by immunohistochemistry. Surprisingly, fibrotic uninvolved airway cells share a similar protein profile to HC airway cells, showing deregulation of SLITs and ROBO pathway as the strongest category. We find that BPIFB1 is the most significantly increased secretome-associated protein in UIP, whereas MUC5AC is the most significantly increased in MA. We conclude that spatial proteomics demonstrates that the fibrotic uninvolved airway cells are abnormal. In addition, fibrotic HC airway cells are enriched in mucin biogenesis proteins with a marked derangement in proteins essential for ciliogenesis. This unbiased spatial proteomic approach will generate novel and testable hypotheses to decipher fibrosis progression.