Pieter qualified as a Paediatrician in 2009 at the University of the Free State. In 2017, he earned the South African Certificate in Asthma Care (NAEP), and in 2018, he obtained a Diploma in Allergology from the College of Family Physicians of South Africa. That same year, he became a certified Allergologist at the University of Cape Town and went on to complete his M.Phil. degree in Allergology in 2019, graduating cum laude.

He worked as a full-time subspecialist in Allergology at MediClinic Bloemfontein whilst also holding a part-time position as a senior consultant at the University of the Free State. In this role, he taught Allergology, Asthma, and Pulmonology to both undergraduate and postgraduate medical students, as well as registrars.

Currently, Pieter serves on the Executive Committee of the South African National Asthma Education Programme (NAEP) and the Allergy Society of South Africa (ALLSA). He is also a member of the South African Allergic Rhinitis Working Group. He has been appointed as an extraordinary consultant at the University of the Free State and is now in full-time private practice at MediClinic Panorama Hospital in Cape Town.