Inorganic pyrophosphatase 2 (PPA2) deficiency is a genetic mitochondrial condition caused by genetic changes in the PPA2 gene. This condition is characterised by acute serious heart complications, including sudden cardiac arrest and heart failure, which can be life-threatening. Episodes are often triggered by alcohol consumption or viral infection.  

The PPA2 protein plays a critical role in the mitochondria to produce energy. When insufficient energy is produced, cells cannot function properly, which may lead to organ dysfunction or failure.  

PPA2 deficiency is more common in infants, children and young adults, although only a small number of cases have been reported in the medical literature to date.  

Below on this page is some information about this condition as well as links to useful resources for Australians living with a rare disease.  

Synonym: PPA2-related mitochondrial inorganic pyrophosphatase 2 deficiency, PPA2-associated sudden cardiac death.

Universal rare disease classifications provide a common language for recording, reporting and monitoring diseases. Please visit the Rare Disease Classifications page for more information about these internationally recognised classifications.

There is no known ORPHA code or ICD-11 classification. 

Rare diseases typically display a high level of symptom complexity. There is often a wide range of symptoms and the symptoms may vary between individuals in terms of its presentation, severity, duration and impact. 

Please speak to your medical team to learn more about the symptoms of this condition. 

Rare diseases are often serious and progressive, exhibiting a high degree of symptom complexity, leading to significant disability. Majority of the estimated two million Australians living with a rare disease meet the Australian Government’s definition for disability (in accordance to the Australian Public Service Commission and Australian Bureau of Statistics), and many experience severe and permanent disability impacts. If you or someone you care for is experiencing disability-related impacts from a rare condition, please speak with a health or disability professional for advice. Information about relevant disability support can be found at the RARE Portal’s Disability Support Information page.

PPA2 deficiency is a genetic condition. It is caused by disease-causing genetic changes (variants) in the PPA2 gene on chromosome 4. 

All individuals have two copies (alleles) of the PPA2 gene – one on each chromosome that is inherited from each parent. PPA2 deficiency is an autosomal recessive condition, which means both copies of the PPA2 gene must have the disease-causing genetic variants. 

Individuals with the genetic variant in only one copy are unaffected but will be a carrier and may pass on that variant to their children. If both parents are carriers (each have a copy of the disease-causing variant), there is a 25% chance the child will inherit both disease-causing variants and have PPA2 deficiency. More information on autosomal recessive inheritance pattern can be found at Centre for Genetics Education: Autosomal recessive inheritance. 

If you would like to learn more about the inheritance and impact of this condition, please ask your doctor for a referral to a genetic counsellor. Genetic counsellors are qualified allied health professionals who can provide information and support regarding genetic conditions and testing. More information about genetic counselling can be found at: 

• Information on Genetic Services 
• The National and State Services pages underneath the ‘Genetic Counselling’ sections listed 

A timely diagnosis is critical for better patient outcomes, the provision of the best possible care and treatment options, access to services and support, increased reproductive confidence and the ability to participate in clinical trials. 

Please speak to your medical team to learn more about the available diagnostic pathways for this condition. 

Please speak to your medical team to learn more about the possible treatment or management options for your condition. Treatment will depend on an individual’s specific condition and symptoms. It is also important to stay connected to your medical team so that you can be made aware of any upcoming clinical trial opportunities.

Healthcare professionals involved in the treatment of PPA2 deficiency may include general practitioners (GP), cardiologists, neurologists, geneticists, metabolic physicians/consultants. The need for different healthcare professionals may change over a person’s lifetime and extend beyond those listed here. 

Clinical care for rare diseases often involves a multidisciplinary team of medical, care and support professionals. Please note that the information provided here is as a guide and that RVA does not necessarily monitor or endorse specific clinics or health experts.

For many rare diseases, palliative care services may be relevant and useful. Palliative care services are available for people (adults, children and their families) living with a life-limiting illness and is not only for end-of-life care. It can also help at any stage of illness from diagnosis onwards, and will look different for different people. Palliative care services provide assistance, support, resources and tools to help people manage their illness and the symptoms, ease pain, and improve comfort and quality of life. If this is relevant to you and you wish to find out more information about palliative care and how it can help you, please visit:

• Australian Institute of Health and Welfare: Palliative care Overview
• Australian Government Department of Health, Disability and Ageing: Palliative care
• Palliative Care Australia

If you know of any relevant care guidelines, please let us know via the Contribute page. 

Individuals living with rare diseases may have complex medical issues and disabilities, which are not always visible. It is often useful to refer to their medical history as well as personal information such as a medical card, doctor’s letter, or if available, a rare disease passport, for relevant information.

If you know of any relevant emergency management guidelines or information relevant to emergency care, please let us know via the Contribute page. 

There are specific considerations around participating in rare disease research, including clinical trials. It is important to be mindful of issues such as data privacy, research ethics, consent and differences in research regulations between Australia and other countries. For more information, please visit the RARE Portal’s Considerations for Participating in Health and Medical Research page.

If you are interested in finding clinical trials for your condition, please visit the following websites; however, there may not be any clinical trials available:

• Australian Clinical Trials
• ClinicalTrials.gov

It is best to discuss your interest in research, including clinical trials,  with your medical team to determine suitability and eligibility.

Australian Organisation: 
We are not aware of any rare disease organisations specifically for PPA2 deficiency in Australia. If you are aware of any organisations, please let us know via the Contribute page. The following organisation provide support for people affected with mitochondrial disease in Australia: 
Mito Foundation
Website: https://www.mito.org.au/  
The Mito Foundation is the only organisation dedicated to supporting and empowering people impacted by mitochondrial disease in Australia. It provides resources and support services for people impacted by mito, and their families, while increasing awareness and understanding of this devastating disease. 

International Organisation: 
Heart of PPA2 (United States of America)
Website: https://heartofppa2.org/ 

Please note that RVA does not monitor or endorse each group/organisation’s operational governance and activities. When engaging with a group, please consider the information on the RARE Portal’s Finding Helpful Peer and Community Supports page.

PPA2 deficiency vary between individuals, and each person’s experience is unique.  

Personal story shared with RVA: Danielle’s story.

If you would like to share your personal story with RVA, please visit the Rare Voices Australia: Share Your Story page. RVA will consider your story for publishing on our website and inclusion on the RARE Portal.

For information on available government and social services that provide support for individuals with a rare disease, please visit the National and State Services pages.

People living with a rare disease often face unique challenges such as diagnostic delays, misdiagnoses, limited treatment options, and limited access to rare disease specialists and support. These challenges may impact people’s emotional wellbeing and quality of life. Many find it helpful to seek mental health and wellbeing support to cope with ongoing stress and uncertainty. Connecting with people who have shared experiences through a support group may also be helpful. Information about relevant mental health and wellbeing support can be found at:

• Mental Health and Wellbeing Support for Australians Living with a Rare Disease
• The National and State Services pages underneath the ‘Mental Health’ sections listed

More information about mitochondrial diseases can be found at RARE Portal: Mitochondrial diseases. 

Online Mendelian Inheritance in Man, OMIM®: #609988 pyrophosphates, inorganic, 2; PPA2 

Human Phenotype Ontology (HPO): PPA2 

Inborn Errors of Metabolism Knowledgebase (IEMbase): #IEM0608: PPA2-related Mitochondrial inorganic pyrophosphatase 2 deficiency 

This page has been developed by Rare Voices Australia (RVA)’s RARE Portal team. If you would like to see more information added to this page, please reach out via the Contact form. If you would like to share relevant resources for this condition, please visit the Contribute page. 

If you are aware of any additional information that may benefit stakeholders with an interest in this page, or if you notice any broken links or inaccurate information, please let us know via the Contribute page.