SAN ANTONIO (AP) — A mother believed to have a disorder that causes her to injure or kill children for attention pleaded guilty Monday to endangering one son by tampering with his hospital feeding tube.

Cynthia Martinez Lyda, 32, pleaded guilty to child injury charges and faces up to 32 years in prison at sentencing. Her plea came on the eve of jury selection in her trial.

Doctors have diagnosed her with Munchausen's syndrome by proxy, a disorder in which caregivers fake or induce illnesses in children to win attention by rescuing them. Mrs. Lyda denies having the condition.

Of her six sons, Aaron died when he was 2 years old of poisoning from ipecac, a syrup used to induce vomiting in children. Another son, Daniel, now 7, fell into a vegetative state at a hospital six years ago when a machine monitoring his respiratory and heart rate was turned off.

And a foster son died when he was 2 years old while in Mrs. Lyda's care in Phoenix in 1993.

Monday's charges pertained to Joseph, 5, who nearly died when he was eight months old.

Officials at Wilford Hall Medical Center on Lackland Air Force Base in San Antonio had installed a camera in the boy's room after becoming suspicious of the mother. The camera showed her disconnecting the tube and blowing into it, forcing air into his stomach.

She was also caught disconnecting a ventilator tube leading into the boy's trachea, depriving him of oxygen for a full minute, and inserting some gauze into his feeding tube, blocking the flow of food.

Mrs. Lyda contended she was trying to unblock the tube.

"At the time, your honor, I intentionally did what I did," Mrs. Lyda said in court. "I understand it was reckless, especially now, five years later. But at the time, I thought it was best for my son."

As part of her plea bargain, charges related to Daniel's case were dropped. No charges were filed against her in the deaths of Aaron and the foster child.

As she being led to jail to await sentencing, she cried and waved to her second husband, with whom she has two sons who have been placed in foster care. The couple has gone to court to regain custody.

Meanwhile, her former husband has custody of the three other sons, Daniel, Joseph and Anthony, 12.

— Kelley Shannon

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