Doctors are confident that Australia swimming's premier breaststroker Samantha Riley will contest the Telstra 2000 Selection Trials, starting in Sydney on May 13, despite a kidney infection which has hospitalised the two-times Olympian this week.

Riley, a former world champion and former world record holder, fell ill during a training camp in Cairns on Wednesday.

She has been in hospital ever since, is expected to remain there over the weekend and with close monitoring and specialised suspervision could be back in the water early next week.

Riley, a two time Olympic bronze medallist over 100 metres breaststroke, is gearing up for her third Olympic team.

The acting Chief Executive officer and Director of Medical Services at the Calvary Hospital in Cairns, Dr Andrew Johnson said today:

"Samantha was admitted to hospital on Wednesday with a kidney infection and has been placed under the care of a kidney specialist.

"She has been on an intravenous antibiotic drip and at the moment she is comfortable.

"Sam will be required to remain in hospital over the weekend and we are confident she will make a full recovery very soon.

"All going well Sam will be back in the water early next week and I can assure you and the rest of Australia that we are doing our utmost to get her back in the pool as quickly as possible."

Riley said from her hospital bed she was improving every day and was looking forward to leaving hospital and getting back in the water.

"I am certainly feeling much better than I was on Wednesday and the doctors and staff at the hospital have been marvellous.

"All going well I'll be out of hospital on Sunday or Monday, earlier if I can twist their arms and I'll be talking to Scott about adjusting our preparation.

"We'll have to modify things but all going well I'll be able to build this into my taper and with the right adjustments I will hopefully be fine by the time it comes to race."

Riley has dominated the Australian breaststroke scene since first bursting onto the scene at the 1991 World Championships in Perth and has since won four world championships