LONDON - Appalling hygiene, a shortage of nursing and unacceptable management contributed to outbreaks of a hospital superbug that killed about 90 patients in southeast England, a damning report said on Thursday.

Media reports said police and the Health and Safety Executive were examining the findings of the Healthcare Commission report to see if criminal charges were appropriate against the Maidstone and Tunbridge Wells NHS Trust.

The commission found that on several occasions nurses had told patients to "go in their beds" rather than helping patients with diarrhoea to get to a commode or bathroom. Some patients were left for hours in wet or soiled sheets.

Patients with the bug, C. difficile, were moved between wards and trust managers had failed to set up a special isolation areas for them. The watchdog blamed a focus on meeting government targets for emergency admissions.

"It took four months to establish an isolation ward exclusively for patients with C. difficile. In our view this was partly because of the pressure on beds and the trust's desire to meet targets," the report said.

The bacterium, commonly transmitted while patients are in the hospital, most often affects those with weak immune systems and the elderly. Figures show cases of the potentially lethal bug in hospitals are on the rise.

The Commission, which described the events at the Maidstone, Kent and Sussex, and Pembury Hospitals as a tragedy, said there had been 1,176 cases of C. difficile during outbreaks between 2004 and 2006.

It estimated about 90 patients had died as a result.

"The clinical management of C. difficile infection in the majority of the patients fell short of an acceptable standard in at least one aspect of basic care," the report said.

"Some patients, who might have been expected to make a full recovery from the condition for which they were admitted, were prescribed broad spectrum antibiotics during their stay in hospital, contracted C. difficile and some died."

The Commission called on the Trust to review its leadership and to take urgent measures to ensure control of infections was treated as a priority.

"What happened to the patients at this trust was a tragedy," said Anna Walker, the Commission's chief executive. "This report fully exposes the reasons for that tragedy, so that the same mistakes are never made again."

Dr Malcolm Stewart, the Trust's Medical Director, acknowledged that there had been a failure of basic systems and the organisation had not been prepared for such an outbreak.

"I would have to say the Trust like all other trusts at that time in the NHS was not prepared for an outbreak of Clostridium difficile of this size and complexity," he told BBC radio.