A failure by doctors at Fiona Stanley Hospital to check an abnormal blood test likely led to the death of patient Jared Olsen, a coroner's report has found.
Mr Olsen, 41, died in March 2015 after having an adverse reaction to a drug given to him to treat his Crohn's disease.
State Coroner Ros Fogliani found medical professionals failed to communicate Mr Olsen's "critical" blood test results with one another, instead entering the details in an electronic system, which was missed due to the shift-work nature of hospital staff.
She said it was "profoundly disturbing" Mr Olsen's father had to live with the knowledge the information that would have likely saved his son's life was on a computer system, but no one checked.
"The inquest highlighted the risks for patients when too much reliance is placed on electronic communications in an environment where clinicians routinely work on rotation and in team environments," she said.
"For the deceased this risk crystallised, with tragic consequences, when a series of events led to significantly abnormal test results being received electronically at FSH, with no clinician becoming aware of them."
Mr Olsen was given an immunosuppressent drug called 6-mercaptopurine (6MP) to treat his inflammatory bowel disease a month before he died.
However, he was unable to metabolise the drug which led to the 41-year-old suffering profound bone marrow suppression, which ultimately led to his death.
The hospital missed a "number of opportunities" to detect the bone marrow suppression and cease the drug treatment before Mr Olsen's death.
Ms Fogliani said communication between medical professionals at the hospital remained a concern.
In a coronial report released last week, she made two recommendations relating to improving the tracking of test results.
"After the deceased's death Fiona Stanley Hospital and PathWest developed a number of procedures in support of improved communication, and the avoidance of a fragmented system of care," she said.
"The issue regarding the proactive conveyance of abnormal test results to the attention of the appropriate treating clinicians, those with the seniority to make the important decisions, remains a concern."