SARS-CoV-2 causes significant multifocal loss of bone trabeculae in the long bones and lumbar vertebrae of all infected hamsters.
The bone loss is associated with SARS-CoV-2-induced cytokine dysregulation, as the circulating pro-inflammatory cytokines not only upregulate osteoclastic differentiation in bone tissues, but also trigger an amplified pro-inflammatory cascade in the skeletal tissues to augment their pro-osteoclastogenesis effect. Our findings suggest that pathological bone loss may be a neglected complication which warrants more extensive investigations during the long-term follow-up of COVID-19 patients.
Using three-dimensional micro-computerized tomography (μCT) scans, the research team identified that SARS-CoV-2 infection had induced severe bone loss from 20% to 50% progressively in particular to the trabecular bone in the long bones and lumbar vertebrae. This effect extended from the acute phase to the chronic phase of infection.