A woman who harassed the wife of a former colleague by sending her hundreds of offensive texts, calls, and tweets has been remanded in custody after she again tweeted about her victim.

Gráinne O'Toole, 41, has been diagnosed with autism and obsessive persecution delusions but is currently undergoing treatment.

O'Toole of Willow Park Grove, Glasnevin, pleaded guilty at Dublin Circuit Criminal Court to harassment of Jennifer Doran between 1 October 2011 and 2 February 2012.

The court was told last year when evidence was heard that O'Toole made over 310 abusive and threatening phone contacts by mobile and landline to Ms Doran, along with occasional tweets. During one month, the number of phone calls averaged 35 a day.

Judge Patrick McCartan had initially adjourned sentencing to October next but the case was re-entered this month after O'Toole again began tweeting about Ms Doran.

Judge McCartan remanded O'Toole in custody until October and directed she should not have access to electronic equipment, computers or phones. He said her medical treatment could continue while she was in custody.

Ms Doran, a marketing consultant, told the court that on 23 April and 22 May last, O'Toole tweeted about her a total of 17 times in a defamatory way to various recipients including business contacts and media outlets.

She also said that after the case was re-entered last week O'Toole began screaming and shouting at her outside court.

Ms Doran told Judge McCartan that she was finding it difficult to deal with the stress and that O'Toole told her she would persecute her for the rest of her life.

"She is obviously not well but I have done nothing to deserve this," said Ms Doran.

Last year Judge McCartan said O'Toole had engaged in a "campaign of harassment" against an entirely innocent person which has adversely impacted on the private, business and personal lives of the victim, her husband and her parents.

He said the whole episode was grounded in the fact that the victim's husband, who had been a supervisor of O'Toole's in work, had showed some kindness towards her, "something she hasn't experienced much in life".

Cathal McGreal BL, defending, submitted O'Toole had difficulties in the past with knowing what she was doing was wrong but said that the current medical report before the court showed some progress towards remorse.

He referred to comments in the medical report outlining that O'Toole knew what she was doing was wrong after she had acted impulsively.

Mr McGreal said that O'Toole's delusion is that all the pain in her life is because of Ms Doran.

He said, as she is currently "medically compliant" and receiving treatment, there is optimism that there will be an end to this once and for all.

Judge McCartan said Ms Doran is a victim who is deserving of the court's comfort and protection but on the other hand there is the accused O'Toole who was "deeply ill".

He said the only way he can deal with the accused until her course of treatment is complete is to remand her in custody and invite her doctor to continue her treatment there.

Judge McCartan said she would not have the means of interfering with her victim in custody.