Newborn screening for primary immunodeficiency diseases should be a health priority, says Dr Jovanka King, a specialist paediatric immunologist.

Australian newborns should be screened for severe immunodeficiency diseases to improve survival and health outcomes for those born without a functional immune system, a paediatric specialist says.

Currently babies are screened, via the heel prick blood test, for more than 40 different conditions, including inborn errors of metabolism and cystic fibrosis.

Dr Jovanka King, a specialist paediatric immunologist and immunopathologist at SA Pathology at the Women's and Children's Hospital, and the University of Adelaide, wants screening to be expanded to include inherited primary immunodeficiency diseases (PID).

She says infants with an inherited PID - of which there are more than 150 types - are in-and-out of hospital with severe and recurrent infections.

Within one year they can face eight or more ear infections, two or more serious sinus infections and two or more bouts of pneumonia.

Babies born with Severe Combined Immunodeficiency (SCID) - which inhibits the production of T and B immune cells - become critically unwell relatively quickly, says Dr King.

"They require long stays in hospital, expensive treatments and medications, intensive care admissions and the condition is associated with a high rate of death and other complications arising from that," Dr King said.

A bone marrow or stem cell transplant offers a cure for SCID and the evidence shows survival is greatly improved when performed before the age of three-and-a-half months, Dr King said.

"Beyond this age, affected babies have a higher burden of infection and other complications due to their untreated disease," she said.

"The only realistic way to achieve the goal of early transplantation for babies with SCID is to diagnose them early in the newborn period, before they develop symptoms of the disease," she said.

But currently a diagnosis can take months and for this reason expanding screening should be a health priority, Dr King told experts at the Pathology Update 2018, the Royal College of Pathologists of Australasia's (RCPA) annual conference held at the weekend.

"Conditions such as SCID are life-threatening, therefore making a diagnosis and starting treatment as early as possible is essential, Dr King said.

Studies in Sweden have demonstrated expanding screening to include PID would save lives.

"Affected infants were detected by an abnormal screening test, which enabled rapid medical assessment, confirmatory testing and commencement of treatment within the first weeks of life," Dr King said.

Doctor King also believes this new screening would also be cost effective.

"Economic analyses performed in other countries have demonstrated that it is more cost effective to screen newborns for SCID than it is to manage a critically unwell child in whom diagnosis and treatment was delayed, which is costly to health systems."