Covid is causing liver damage that lasts months after infection, according to new research.
Researchers at Massachusetts General Hospital, Boston, found that Covid-positive patients had “statistically significant” higher liver stiffness than the rest of the population.
Liver stiffness could indicate long-term liver damage such as inflammation or fibrosis, the buildup of scar tissue in the liver.
Most healthy liver tissue decreases over time causing the liver to stop working properly, and in severe cases, progressive fibrosis can lead to cancer or liver failure.
Dr Firouzeh Heidari, a researcher at Massachusetts General Hospital, said their findings show that the damage caused by Covid persists for a long time.
He said: “Our study is part of emerging evidence that Covid-19 infection can lead to liver damage that lasts well after acute illness.
“We do not yet know whether the elevated liver stiffness seen after COVID-19 infection will lead to adverse patient outcomes.”
The researchers compared patients who had Covid with two control groups and each received an ultrasound shear wave elastography.
The Covid-positive patients had a high median liver stiffness of 7.68 kPa, compared with 5.99 kPa of stiffness in those who didn’t have Covid.
Patients were organized into one of three groups, based on whether they had received elastography and tested positive for Covid.
The evaluation done at Massachusetts General Hospital measures how stiff the fabric is.
Covid participants received a positive PCR test at least 12 weeks before the exam.
There were 31 in the Covid group and 50 in the control group who had been tested but had only tested negative on PCR tests during the pandemic.
Another 50 people, who had undergone an elastography exam before the pandemic, formed the second control group.
Dr. Heidari said: “We are currently studying whether the severity of acute Covid-related symptoms is predictive of the severity of long-term liver injury.
“We hope to enrich our existing database with additional patient data and a broader scope of co-variables to better understand the post-acute effects of Covid-19 within the liver.”
The team believes that the higher median stiffness among the pre-pandemic control group, compared to the pandemic control group, was due to changing baseline patterns during the pandemic and because the pandemic control group was older.
The mean age of the Covid-positive group was 53.1 years, 55.2 years for the pandemic control group, and the pre-pandemic cohort averaged 58.2. In total, 67 were women.
In the Covid-positive group, elastography tests occurred on average 44 weeks after a positive PCR result.
The research was presented at the annual meeting of Radiological Society of North America.