Evidence map›Paper›PMID 41620635›Full record

Observational studyBMC nephrology2026

Renal microthrombosis and thrombomodulin deficiency in COVID-19-associated acute kidney injury.

Matilda Bekhet, Amanda Marks-Hultström, Gül Gizem Korkut, Angelina Schwarz, Jaakko Patrakka, Elisabet Englund, Marie Jeansson

Abstract readObservational Study
In one paragraph

Observational study in BMC nephrology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Matilda BekhetDepartment of Medicine Huddinge, Karolinska Institutet, Blickagangen 16, Huddinge, Sweden.
Amanda Marks-HultströmDepartment of Immunology, Genetics, and Pathology, Uppsala University, Uppsala, Sweden.
Gül Gizem KorkutDepartment of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden.
Angelina SchwarzDepartment of Clinical Sciences, Karolinska Institutet, Huddinge, Sweden.
Jaakko PatrakkaDepartment of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden.
Elisabet EnglundDivision of Pathology, Department of Clinical Sciences, Lund University, Lund, Sweden.
Marie JeanssonDepartment of Medicine Huddinge, Karolinska Institutet, Blickagangen 16, Huddinge, Sweden. marie.jeansson@ki.se.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundSevere COVID-19 frequently involves multi-organ dysfunction, including acute kidney injury (AKI), which affects up to 85% of critically ill patients. While both direct viral infection and systemic effects are implicated, the role of renal microthrombosis remains poorly defined in COVID-19 and AKI. Angiopoietin-2, a pro-inflammatory cytokine, and cleaved thrombomodulin is elevated in plasma in severe COVID-19 and has been linked to endothelial dysfunction and hypercoagulability. We hypothesize that renal microthrombi can contribute to decreased kidney function in critically ill COVID-19 patients.

methodsWe performed histopathological and molecular analyses of postmortem kidney tissue from seven critically ill COVID-19 patients. Control tissue was obtained from nephrectomy specimens (n = 6) and postmortem tissue (n = 7). We assessed microthrombi, tubular necrosis, glomerulosclerosis, fibrosis, and expression of angiopoietin-2 and thrombomodulin. Immunofluorescence and SARS-CoV-2 nucleoprotein staining were used alongside clinical data.

resultsAKI was observed in six of seven COVID-19 patients. Compared to controls, COVID-19 kidneys showed a significant reduction in tubular nuclear area (P < 0.0003), presence of viral antigen in tubular epithelium, and marked glomerular and peritubular microthrombi (15.2 vs. 1.3 thrombi/mm²; P < 0.0001). THBD expression was significantly reduced bith peritubular capillaries and glomeruli in COVID-19 kidneys. Glomerulosclerosis, glomerular area, and tubulointerstitial fibrosis were variable in both control and COVID-19 patients with no significant differences.

conclusionsThis study identifies widespread renal microthrombi, tubular necrosis, and reduced THBD expression in COVID-19 patients with AKI, supporting a role for endothelial dysfunction and microvascular thrombosis in COVID-19-associated renal injury. The data implicates the disruption of endothelial anticoagulant signaling through thrombomodulin as a contributing mechanism.

Indexed as

Acute Kidney InjuryCOVID-19KidneyThrombomodulinThrombosisAgedAngiopoietin-2FemaleHumansMaleMiddle AgedSARS-CoV-2Angiopoietin-2THBD protein, humanThrombomodulinAcute kidney injuryAngiopoietin-2COVID-19ThrombomodulinThrombosis

Identifiers

PMID41620635
PMCPMC12937520

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.