Nairobi – Medical officials linked to a brain surgery mix-up at a Kenyan hospital last month have reportedly been allowed back to work.The Kenyatta National Hospital (KNH) had suspended a trainee surgeon, an anaesthetist and two nurses after performing a brain surgery on the wrong patient. This was one of the worst cases of medical malpractice to become public at the hospital, reports said.According to Kenya's Daily Nation newspaper, the hospital's board on Thursday said it had since left investigations into the mishap to the Kenya Medical Practitioners and Dentists Board (KMPDB)."Effective immediately, the board will no longer engage in any disciplinary matters as we will leave it to the KMPDB," said Mr Mark Bor, chairperson of the KNH board was quoted as saying.This came after Medical Board Chair Prof George Magoha "called for their reinstatement, saying that due process will still be followed after the investigations are complete", the report said.Two men had been wheeled into the hospital about two weeks ago week – one needed a surgery to remove a blood clot in his brain "while the other only required nursing and medication to heal a trauma swelling in his head".KEEP UPDATED on the latest news from around the continent by subscribing to our FREE newsletter, Hello Africa.FOLLOW News24 Africa on Twitter and Facebook. There was, however, "a horror mix-up of tags", which resulted in the wrong man being wheeled into theatre and his skull opened.Doctors only realised the mistake hours into the surgery "when they discovered there was no blood clot in the brain".Over 500 senior doctors had on Monday downed their tools in protest against the supersession of their colleague. The doctors' union, Sammy Oroko, said at the time that the suspension of the surgeon was a "knee jerk reaction which will not solve the underlying problems at the hospital".The doctor’s union wanted an overhaul of the hospital operations, including digitisation of the hospital’s booking systems and setting up more theatres.They said that the boycott was an opportunity to re-examine the entire system at the Kenyatta Hospital, BBC said.