PITTSBURGH — Children suffering from high levels of sodium in their blood — like a 4-month-old infant allegedly poisoned with salt water by his mother this week — are at high-risk for permanent brain damage, if they survive, doctors said Friday.

The doctors, all specialists in children's health, said high levels of salt cause the brain to shrink and cells to burst, leading to seizures, brain bleeding and even coma — all injuries that can lead to permanent damage.

None of the doctors are directly involved with the case of Noah King, an infant from Tennessee whose mother, Amber Brewington, has been arrested in Pittsburgh on charges she injected him at least five times with salt water.

But all agreed that the level of sodium Noah had when he arrived at Children's Hospital of Pittsburgh — 215 units per deciliter — was well above normal levels of about 135 to 145, and could not have been caused by any natural illness. Noah is in critical condition.

"Death is a possibility of high serum sodiums, and the higher the sodium, the greater the chance of permanent neurological injury or death," said Dr. Basil Zitelli, a pediatrician at the hospital.

Brewington, 21, tried to poison her son by repeatedly injecting salt water into his hospital feeding tube in what she claimed were attempts to hasten the death of a sick and suffering child, police said.

She is in the Allegheny County Jail on a charge of attempted homicide. A preliminary hearing is scheduled for Wednesday, but she does not yet have an attorney listed. Brewington told police she suffers from severe postpartum depression.

Her grandfather, Clarence Jenkins, told a Nashville TV station that the allegations are untrue.

Jenkins said Noah had salmonella poisoning three months ago and suffered from dehydration, seizures and a stroke.