Written by Professor Andrew Mallett, Director of Clinical Research & Nephrologist, Townsville University Hospital, Professor of Medicine, James Cook University, and Clinical Fellow, Institute for Molecular Bioscience, The University of Queensland
It has now almost been one year since genetic testing for suspected inherited kidney disease was listed with the Australian Medicare benefit scheme. This has been a critical step forward for the Australian kidney community as it now enables more straightforward and equitable access to indicated genetic or genomic testing. Whilst it is somewhat too early to know as yet, the full impact of this new Medicare listing, it is however an opportune time to reflect on how far we have come in Australia over the last decade. The very first multidisciplinary kidney genetics clinic only commenced in August 2013 in Brisbane(1), but as we now approach the first decade anniversary of this clinic, it has been joined by no less than 18 similar clinics all around Australia (kidgen). Many of these services are also providing telephone and telehealth components that are further enabling better access for all Australians who might need to ask the question as to whether there is a genetic cause for their kidney disease.
So who, what and why? There are very good reasons why it is strongly suggested that a family history of kidney disease can be a personal risk factor for developing it. Approximately 10% of adults affected by kidney disease (2) are thought to have an underlying diagnosable genetic form. This is higher in children, where it is thought that this may be as high as 50%, especially in young children who have been diagnosed with kidney disease, considering that about one in 8 Australian adults has a marker of kidney disease, there may be a much higher number of people with potential genetic kidney disease then we’ve thought was the case in the past.
Further complicating matters, genetic kidney disease isn’t just one thing or clinical entity. In fact, there is an entire spectrum of potential genetic kidney diseases, many of which have unique or distinct features and are often individually rare (rarevoices). They can range from cystic forms of kidney disease such as ADPKD or ARPKD (PKD Australia), through to glomerular conditions such as Alport syndrome, tubulopathies including Gitelman syndrome, complement conditions such as Ahus Alliance Action, structural disorders (Congenital Anomalies of the Kidney and Urinary Tract; CAKUT) and even genetic kidney cancer predisposition syndromes. These conditions and the genes that are associated with them are being methodically characterised (3) (4) which is making it easier for clinicians to order appropriate genetic testing, when indicated or required.
There are lots of potential reasons why a genetic test might be helpful for an individual patient or family (5) however, these are often very specific to the individual, patient, kidney condition and situation at that point in time (6). Research undertaken here in Australia has found that there can be the potential to avoid some invasive procedures, such as kidney biopsy, in addition to changing, surveillance or treatment (7) and that it can be cost-effective (8). Emerging international evidence is further supporting and broadening this (9). In addition to providing evidence of other potential uses such as in family or reproductive planning (10).
In short, there are a lot of different ways in which a genetic test might be of assistance but the individual one being experienced by a specific patient or family is just that, individual. The care that we provide this needs to be individualised and personalised accordingly. We are fortunate in Australia to have access to publicly funded genomic testing for suspected genetic kidney disease and further that substantial clinical service development has occurred in recent years to enable provision of genomic-empowered kidney care. Where will we be in 10 years? This is currently unclear and there is need to identify new treatments for genetic kidney diseases, however, it is more likely today to be a brighter future than it was 10 years ago.
Andrew.
(1) https://metronorth.health.qld.gov.au/rbwh/genetic-health-queensland/information-for-practitioners/clinical-services/renal-genetics-clinic; https://pubmed.ncbi.nlm.nih.gov/26821098/
(2) https://pubmed.ncbi.nlm.nih.gov/24980890/; https://pubmed.ncbi.nlm.nih.gov/30586318/
(3) https://clinicalgenome.org/working-groups/clinical-domain/clingen-kidney-disease-clinical-domain-working-group
(4) https://panelapp.agha.umccr.org
(5) https://pubmed.ncbi.nlm.nih.gov/35460632/
(6) https://pubmed.ncbi.nlm.nih.gov/36093902/
(7) https://pubmed.ncbi.nlm.nih.gov/32939031/
(8) https://pubmed.ncbi.nlm.nih.gov/34805637/
(9) https://pubmed.ncbi.nlm.nih.gov/36753701/
(10) https://pubmed.ncbi.nlm.nih.gov/32855195/