according to a new study presented at the Society of Critical Care Medicine’s 2023 Critical Care Congress.
“We have had a lot of success using genome sequencing to help not only with diagnosis, but also changes in management,” lead author Katherine Rodriguez, MD, a pediatric critical care fellow physician at Rady Children’s Hospital, San Diego, told this news organization.
However, data on the use of rapid whole genome sequencing (rWGS) in the pediatric intensive care unit (PICU) are limited, and data from multiple institutions are lacking, Dr. Rodriguez said. In the current study, data from multiple hospitals allowed the researchers to examine differences in management across institutions, she said.
Dr. Rodriguez, with principal investigator Nicole Coufal, MD, also of Rady Children’s, and colleagues conducted the study at three children’s hospitals from March 2019 to July 2022. The study population included 80 children whose origin of illness was uncertain. The patients underwent rWGS testing in the PICU or cardiac ICU setting. The patients ranged in age from 0 to 17 years; 64% were younger than 1 year, (mean age, 2.8 years); 56% were male, and 59% were White.
After rWGS testing, 65% of the children were positive for a genetic variant. The data prompted changes to care for 42% of these patients; 38% of the changes occurred during the patient’s PICU stay, including medication changes and procedures that were either avoided or completed.
The remaining 62% of the changes were subacute and affected management for the remainder of the child’s hospitalization and after discharge, Dr. Rodriguez explained in her presentation.
The average turnaround time for the testing was 10 days, which is important to an intensivist, who may have been hesitant to order tests because of the time involved, Dr. Rodriguez said. The current study shows that “we can get test results in a reasonable time to make meaningful changes in care,” she told this news organization.
Choosing which patients to test can be a challenge for clinicians, Dr. Rodriguez acknowledged. “We have gotten a sense of which patients are likely to have diagnostic or not diagnostic genomes, but it is also a gut feeling,” she said.
“If this child is your patient and you are concerned, if they seem sicker than expected, or have a concerning family history, then send the test,” she said. “It is becoming more affordable, and can come back quickly enough to guide treatment while the patient is still in the ICU.”
In the current study, the greatest diagnostic utility appeared in patients with cardiac symptoms, such as congenital heart disease, sudden cardiac arrest, or suspected channelopathy, Dr. Rodriguez said in her presentation.
Patients with suspected neurological disease had a 50% rate of molecular diagnosis. “Interestingly, 74% of patients with respiratory disease where an underlying genetic etiology was suspected received a molecular diagnosis,” although rWGS was not applied to general populations with RSV or other respiratory illnesses, she said.
In her presentation, Dr. Rodriguez shared examples of how genetic testing had a dramatic impact on patient survival. In one case, a 14-year-old girl presented in cardiac arrest and was found to have new-onset dilated cardiomyopathy. Whether the etiology was acquired or infectious and possibly reversible or genetic was unclear, she said.
“A diagnostic genome result within 48 hours indicated a genetic etiology,” she said. The patient was listed for heart transplant despite the incomplete infectious workup, and received a successful heart transplant 1 week after admission, Dr. Rodriguez said.
Guidelines for which PICU patients should undergo genetic testing do not yet exist, Dr. Rodriguez told this news organization. “We are trying to find some more meaningful parameters where we can say that a patient has a high pretest possibility of a genetic condition,” she said.
“Increasing availability of rWGS can significantly impact patient care and assist families in making difficult decisions during times of critical illness,” she said.
Insurance coverage and testing access are improving, said Dr. Rodriguez. Medicaid policies exist for neonates/infants in the ICU in several states, including Oregon, California, Michigan, Maryland, and Louisiana, she said. In some areas, hospitals may pay for testing for these children if insurance will not, she added.
Dr. Rodriguez and colleagues are continuing to enroll patients in a prospective study of the impact of rWGS, with the addition of a fourth study site and inclusion of family surveys. “We also will be looking at a secondary analysis of cost savings and benefits,” she said.
Ultimately, the current study should be empowering to physicians, “especially if they don’t have good access to geneticists,” Dr. Rodriguez said in an interview.
The study received no outside funding. Dr. Rodriguez reports no relevant financial relationships.
A version of this article first appeared on Medscape.com.