MUMBAI: A 10-month-old infant from Goregaon , Mumbai, has lost his sense of recognition and is unable to identify familiar faces, including his parents’, following a neurological complication caused by influenza H1N1 . The extensive brain impairment in the baby has sent warning bells among clinicians that the viral infection can go beyond the respiratory system.Over the last one month paediatric neurologists have treated at least five to six confirmed cases of H1N1 in children, who have presented with neurological complications primarily, instead of the usual fever, cough and throat infection. Two of these children continue to be hospitalised. The neuro experts have strongly advised physicians to think of H1N1 while treating unexplained seizures or inflammation in the brain. All the babies required ventilation and ICU care.The Goregaon infant was brought to the Surya Child Care Hospital in Santacruz about three weeks ago in an extremely critical condition. The baby was unconscious, breathing with difficulty and almost slipping into coma. While a cerebrospinal fluid (CSF) test ruled out dengue and other infections such as herpes, the MRI scan was the red flag.“It showed bleeding in the thalamus, an important region that relays sensory and motor signals. We diagnosed the baby with acute necrotising encephalopathy of childhood (ANEC), a kind of brain damage, which can be caused by viral infections. In this case, it was H1N1. Viral infections have been associated with ANEC but they are extremely rare,” said paediatric neurologist Dr Omkar Hajirnis, who consults at Surya Hospital. He said that the baby has been moved out of ICU recently but he has lost his sense of recognition. “ANEC is also known to cause loss of vision which we are yet to confirm in this child,” he said, adding that he himself has treated four children with brain involvement.A four-year-old child from south Mumbai was taken to the emergency of Jaslok Hospital in Peddar road with continuous seizures about three weeks ago. Paediatric neurologist Dr Anaita Hegde recalled that the boy came in a state of shock with altered sensorium.“We suspected H1N1 and he came positive. He was also from a compromised category, as he had an underlying rare metabolic disorder, known to cause seizures. We kept him in isolation and treated with oseltamivir.” The doctor added that the boy was fortunate to escape any brain damage. “His MRI was normal. Luckily, his mother brought him in time. A few more hours at home could have changed the picture completely,” she said.Doctors say that H1N1 is rampant this year but better diagnosis is bringing such complications to light. “We know H1N1 by involvement of lungs but we must consider that very few H1N1 could have involvement of the brain,” said Dr Bhupendra Avasthi, director of Surya Hospital. Besides Surya, a child with brain complication is currently undergoing treatment at Fortis Hospital, Mulund.Interestingly, the twin brother of the Goregaon child, who too was infected along with the parents, has recovered from the viral infection completely. Paediatric neurologist Dr Vrajesh Udani, who consults at Mahim ’s PD Hinduja Hospital, said that about 30% of H1N1 affected patients have neurological symptoms like headache, irritability, but encephalopathy is extremely rare.Maharashtra, including Mumbai, has been reeling under an H1N1 outbreak this year. The death toll for the state touched 300 on Sunday.