Brazilian President Jair Bolsonaro visited the Surgery wing of the Armed Forces hospital in Brasilia on Thursday night, leaving without speaking to reporters, with a source familiar with the matter saying the president had felt discomfort in his abdomen.
The source said a medical team was weighing whether to replace mesh that was put in Bolsonaro's abdomen to treat a prior hernia.
Bolsonaro, 64, was stabbed by an attacker on the campaign trail in 2018 and has repeatedly sought follow-up treatment for the injury and related issues.
He has undergone four surgeries since the attack, with the most recent operation using the mesh to correct a hernia in the area where he was stabbed.
Thursday's hospital visit was not on Bolsonaro's official agenda for the day, which was set to end after he visited the state of Minas Gerais where heavy rains and flooding last week led to the deaths of more than 50 people.
It was precisely over flying the flooded areas that the president complained of abdominal pain and was flown back to Brasilia where his personal doctor recommended Bolsonaro visit the hospital.
There is no official agenda on Friday for the Brazilian president.