By Vicky Ntetema
BBC News, Dar es Salaam
A Tanzanian hospital has mixed up two patients who share the same first name, resulting in a surgery blunder.
Migraine sufferer Emmanuel Mgaya recovering from knee surgery
Emmanuel Didas, who was admitted for a knee operation after a motorbike accident, is now unconscious in intensive care after head surgery.
Meanwhile, chronic migraine sufferer Emmanuel Mgaya is recovering from an unplanned knee operation.
Some angry relatives are demanding a full investigation into the incident at Muhimbili Hospital in Dar es Salaam.
Doctors at Muhimbili National and Referral Hospital are unwilling to comment on the incident which occurred last week, but was not officially reported.
The Ministry of Health and Social Welfare says it has ordered an inquiry into the medical blunder.
"This is negligence because a doctor must know that a knee is positioned very far from the head," said one of Mr Didas's relatives.
The family, who are keeping vigil outside the intensive care ward, has not yet been told the details of his unexpected head surgery.
"The doctors did not even tell us that Emmanuel had had a head operation. It is the responsibility of a doctor to ensure patients get the right treatment," the relative said.
Outside a surgical ward, the relatives of secondary student Emmanuel Mgaya explained how they felt the unfortunate accident had come about.
"We think maybe the nurses mixed the patients' files because they were admitted in the same ward and sharing the same first names," one said.
Mr Mgaya had recently developed acute headaches while studying for his final secondary school exams and was referred to Muhimbili Hospital from a remote district in the Southern Highlands of Tanzania.
"We still have faith in the doctors. What has happened has not made us lose faith," his upbeat family said.
"And we have already spoken to the hospital director who has reassured us that the qualified consultants will operate on our Emmanuel Mgaya. So we are not worried."
But Mr Didas's family remain shocked and dismayed.
"A person has several names. The medical staff should have checked this before the operation," one said.