Mark A. Walterfang

Mark A. Walterfang

MBBS (Honours), FRANZCP, PhD, DMedSci, Graduate Certificate in Business

Neurologist

Over 30+ years of experience

MalešŸ“ Parkville

About of Mark A. Walterfang

Mark A. Walterfang is a neurologist based in Parkville, VIC 3052, Australia.


Neurology is about how the brain, nerves, and muscles work together. Dr Walterfang looks after people with a wide range of neurological problems. This can include memory and thinking changes, long-term movement issues, and seizure disorders. At times, care also involves brain and nerve conditions that affect swallowing, speech, and daily function.


Over time, many patients come with concerns around dementia and other types of cognitive decline, including frontotemporal dementia and Alzheimer’s disease. Some people also need help with movement disorders such as Parkinson’s disease, chorea, and other causes of shaking or stiffness. For others, the main focus is seizures, including absence seizures and generalised tonic-clonic seizures, along with the risk factors around them.


There are also rarer conditions involved in his work. This includes some genetic and metabolic brain disorders, where early symptoms can be subtle and then change over time. Examples in his clinical focus include Niemann-Pick disease and acid sphingomyelinase deficiency (ASMD), as well as other metabolic conditions that can affect the nervous system. In some cases, people are also dealing with developmental speech and language difficulties, or conditions linked to abnormal brain development.


Dr Walterfang’s experience spans more than 30 years. He works with adults and families, and understands that families often need clear explanations and steady guidance, not jargon. The aim is to help people make sense of symptoms, work out what’s going on, and plan next steps that fit real life.


Education is a strong part of his background. He holds MBBS (Honours), and he is a Fellow of the Royal Australian and New Zealand College of Psychiatrists (FRANZCP). He also has a PhD from the University of Melbourne, and a Doctorate of Medical Science (DMedSci), again through the University of Melbourne. More recently, he completed a Graduate Certificate in Business (Health Design / Exec Grad Certificate Business) at Monash University.


Research also features in his career. He has publications across neurological and related topics, and he has been involved in clinical research activities and evidence-building work that can help guide care for complex conditions. Clinical trials aren’t always the right fit for every person, but research helps make treatment and follow-up more informed.


If you’re looking for a neurologist in Parkville, Dr Mark A. Walterfang is one option. His work covers common presentations like dementia and seizures, and it also reaches into the more complex, less common neurological disorders.

Education

  • MBBS (Honours); University of Queensland; 1993
  • FRANZCP, Fellowship of the Royal Australian and New Zealand College of Psychiatrists; Royal Australian and New Zealand College of Psychiatrists (RANZCP) ; 2000
  • PhD (Doctor of Philosophy); University of Melbourne; 2010
  • Doctorate of Medical Science (DMedSci); University of Melbourne; 2023
  • Graduate Certificate in Business (Health Design / Exec Grad Certificate Business); Monash University; 2023

Services & Conditions Treated

HistiocytosisNiemann-Pick DiseaseNon-Langerhans-Cell HistiocytosisReticulohistiocytomaDementiaFrontotemporal DementiaAlzheimer's DiseaseDevelopmental Dysphasia FamilialHuntington DiseaseMarchiafava Bignami DiseaseMovement DisordersSuccinic Semialdehyde Dehydrogenase DeficiencyAbsence SeizureAcid Sphingomyelinase Deficiency (ASMD)AnorexiaBipolar Disorder (BPD)Brown SyndromeBulimiaCACH SyndromeChorea-AcanthocytosisCorticobasal DegenerationCreutzfeldt-Jakob DiseaseDrug Induced DyskinesiaDysarthriaGeneralized Tonic-Clonic SeizureHepatocerebral DegenerationHerpes Simplex EncephalitisMajor DepressionMetachromatic LeukodystrophyObsessive-Compulsive Disorder (OCD)Olivopontocerebellar AtrophyParkinson's DiseasePhenylketonuria (PKU)PorphyriaProgressive Supranuclear PalsyProgressive Supranuclear Palsy AtypicalSchizophreniaSeizuresSpinocerebellar AtaxiaSplenomegalySupranuclear OphthalmoplegiaSwallowing DifficultyTraumatic Brain InjuryVascular DementiaWilson Disease

Publications

5 total
Blood biomarker profiles in young-onset neurocognitive disorders: A cohort study.

The Australian and New Zealand journal of psychiatry • January 18, 2025

Oneil Bhalala, Jessica Beamish, Dhamidhu Eratne, Patrick Summerell, Tenielle Porter, Simon Laws, Matthew Kang, Aamira Huq, Wei-hsuan Chiu, Claire Cadwallader, Mark Walterfang, Sarah Farrand, Andrew Evans, Wendy Kelso, Leonid Churilov, Rosie Watson, Nawaf Yassi, Dennis Velakoulis, Samantha Loi

Background: Young-onset neurocognitive symptoms result from a heterogeneous group of neurological and psychiatric disorders which present a diagnostic challenge. To identify such factors, we analysed the Biomarkers in Younger-Onset Neurocognitive Disorders cohort, a study of individuals <65 years old presenting with neurocognitive symptoms for a diagnosis and who have undergone cognitive and biomarker analyses. Methods: Sixty-five participants (median age at assessment of 56 years, 45% female) were recruited during their index presentation to the Royal Melbourne Hospital Neuropsychiatry Centre, a tertiary specialist service in Melbourne, Australia, and categorized as either early-onset Alzheimer's disease (n = 18), non-Alzheimer's disease neurodegeneration (n = 23) or primary psychiatric disorders (n = 24). Levels of neurofilament light chain, glial fibrillary acidic protein and phosphorylated-tau 181, apolipoprotein E genotype and late-onset Alzheimer's disease polygenic risk scores were determined. Information-theoretic model selection identified discriminatory factors. Results: Neurofilament light chain, glial fibrillary acidic protein and phosphorylated-tau 181 levels were elevated in early-onset Alzheimer's disease compared with other diagnostic categories. A multi-omic model selection identified that a combination of cognitive and blood biomarkers, but not the polygenic risk score, discriminated between early-onset Alzheimer's disease and primary psychiatric disorders (area under the curve ⩾ 0.975, 95% confidence interval: 0.825-1.000). Phosphorylated-tau 181 alone significantly discriminated between early-onset Alzheimer's disease and non-Alzheimer's disease neurodegeneration causes (area under the curve = 0.950, 95% confidence interval: 0.877-1.00). Conclusions: Discriminating between early-onset Alzheimer's disease, non-Alzheimer's disease neurodegeneration and primary psychiatric disorders causes of young-onset neurocognitive symptoms is possible by combining cognitive profiles with blood biomarkers. These results support utilizing blood biomarkers for the work-up of young-onset neurocognitive symptoms and highlight the need for the development of a young-onset Alzheimer's disease-specific polygenic risk score.

Disease-Modifying, Neuroprotective Effect of N-Acetyl-l-Leucine in Adult and Pediatric Patients With Niemann-Pick Disease Type C.

Neurology • June 13, 2025

Marc Patterson, Uma Ramaswami, Aimee Donald, Tomas Foltan, Matthias Gautschi, Paul Gissen, Andreas Hahn, Simon Jones, Richard Kay, Miriam KolnikovĆ”, Julien Park, Stella ReichmannovĆ”, Mark Walterfang, Pierre Wibawa, Marianne Rohrbach, Kyriakos Martakis, Tatiana Bremova Ertl

Objective: N-acetyl-l-leucine (NALL) has been established to improve the neurologic manifestations of Niemann-Pick disease type C (NPC) after 12 weeks in a placebo-controlled trial. In the open-label extension phase (EP) follow-up, data were obtained after 12 and 18 months to evaluate the long-term effects of NALL for NPC. Methods: This is an ongoing, multinational, multicenter EP. Patients with a genetic diagnosis of NPC aged 4 years or older who completed the placebo-controlled trial were eligible to continue in the EP and receive orally administered NALL 2-3 times per day in 3 tiers of weight-based dosing. The primary end point is the modified 5-domain NPC Clinical Severity Scale (NPC-CSS) (range 0-25 points; lower score representing better neurologic status); data from the EP cohort are compared with the expected annual trajectory of decline (i.e., disease progression) established in natural history studies. Analyses are also performed on exploratory end points, including the 15-domain and 4-domain NPC-CSSs and the Scale for Assessment and Rating of Ataxia (SARA). Results: Fifty-three patients aged 5-67 years (45.3% female, 54.7% male) were enrolled in the EP. After 12 months, the mean (±SD) change from baseline on the 5-domain NPC-CSS was -0.27 (±2.42) with NALL vs +1.5 (±3.16) in the historical cohort (95% CI -3.05 to -0.48; p = 0.009), corresponding to a 118% reduction in annual disease progression. After 18 months, the mean (±SD) change was +0.05 (±2.95) with NALL vs +2.25 (±4.74) in the historical cohort (95% CI -4.06 to -0.35; p = 0.023). The 15-domain and 4-domain NPC-CSSs were consistent with the 5-domain NPC-CSS. The improvements in neurologic manifestations demonstrated in the placebo-controlled trial on the primary SARA end point were sustained over the long-term follow-up. NALL was well tolerated, and no treatment-related adverse events or serious reactions occurred. Conclusions: Treatment with NALL was associated with a significant reduction in NPC disease progression after 12 and 18 months, demonstrating a disease-modifying, neuroprotective effect. The trial is registered with ClinicalTrials.gov (NCT05163288; registered December 6, 2021), EudraCT (2021-005356-10). The first patient was enrolled into the EP on March 8, 2023. The trial was funded by IntraBio Inc. Methods: This study provides Class IV evidence that NALL reduces disease progression in NPC.

Strong diagnostic performance of plasma ptau217 for CSF biomarker-defined young-onset Alzheimer disease in a diagnostically heterogeneous clinical cohort.

Journal Of Neurology • September 21, 2024

Dhamidhu Eratne, Qiao-xin Li, Courtney Lewis, Christa Dang, Matthew J Kang, Jasleen Grewal, Samantha Loi, Mark Walterfang, Andrew Evans, Charles Malpas, Steve Pedrini, Ralph Martins, Pratishtha Chatterjee, Henrik Zetterberg, Kaj Blennow, Samuel Berkovic, Alexander Santillo, Steven Collins, Colin Masters, Dennis Velakoulis

Objective: We investigated diagnostic utility of phosphorylated tau 217 and 181 (ptau217, ptau181), glial fibrillary acidic protein (GFAP), amyloid beta 42 and 40 (Aβ42, Aβ40), and neurofilament light (NfL) to distinguish biomarker-defined Alzheimer disease (AD) from non-AD conditions, in a heterogenous clinical cohort of younger people. Methods: Plasma biomarkers were analysed using ultrasensitive technology, and compared in patients with CSF Alzheimer disease profiles (A+T+) to other CSF profiles (Other). Results: Seventy-nine patients were included, median age 60.8 years: 16 A+T+, 63 Other. Ptau217, ptau181, GFAP were significantly elevated in A+T+ compared to Other (3.67 vs 1.12 pg/mL, 3.87 vs 1.79 pg/mL, 189 vs 80 pg/mL, respectively). ptau217 distinguished AD from Other with 90% accuracy (88% specificity, 100% sensitivity). ptau217 also demonstrated strong diagnostic performance for clinically diagnosed AD. Conclusions: Plasma ptau217 has strong diagnostic performance in distinguishing CSF biomarker-defined AD in a clinically relevant, younger cohort of people with symptoms, adding further weight for a simple diagnostic blood test for AD as a cause of a patient's symptoms.

Implications of the choroid plexus in Niemann-Pick disease Type C neuropathogenesis.

Brain, Behavior, And Immunity • August 15, 2024

Raquel Van Gool, Mariesa Cay, Boyu Ren, Kailey Brodeur, Emma Golden, Benjamin Goodlett, Edward Yang, Tom Reilly, Caroline Hastings, Elizabeth Berry Kravis, Pui Lee, Maria Di Biase, Vanessa Cropley, Christos Pantelis, Dennis Velakoulis, Ann Shinn, Walla Al Hertani, Mark Walterfang, Jaymin Upadhyay

Background: Niemann-Pick Disease Type C (NPC) is an ultra-rare disorder characterized by progressive psychiatric and neurologic manifestations, with late infantile, juvenile, and adolescent/adult presentations. We examined morphological properties of the choroid plexus, a protective blood-cerebrospinal fluid barrier, in NPC, and their relationship with neurodegeneration, clinical status, and circulatory markers. This study also determined whether choroid plexus morphology differentiates between NPC and more prevalent illnesses, schizophrenia (SZ) and bipolar disorder (BD), which have overlapping psychiatric symptoms with adolescent and adult-onset NPC and are associated with misdiagnosis. Methods: Patients with NPC were assessed using neuroimaging, clinical instruments, and plasma protein quantification focusing on inflammatory markers. Morphological properties (i.e., choroid plexus volumes) were compared between patients with NPC (n = 17), SZ (n = 20), BD (n = 24), and healthy controls (HCs, n = 106). Results: Choroid plexus enlargement (p < 0.05) and reduced thalamic volumes (p < 0.05) were observed in NPC patients versus HCs and SZ or BD patients. A logistic regression model with choroid plexus and thalamic volumes as predictors yielded high prediction accuracy for NPC vs. HCs, NPC vs. SZ, and NPC vs. BD (area under the receiver operating characteristics curve [AUROC] of 1). Choroid plexus volumes were negatively correlated with left (p = 0.009-0.012) and right (p = 0.007-0.025) thalamic volumes, left (r = -0.69, p = 0.003) and right (r = -0.71, p = 0.002) crus I of the cerebellum, and greater severity on the NPC-Suspicion Index psychiatric subscale (ρ = 0.72, p = 0.042). Targeted protein expression quantification revealed differential expression of TGFA, HLA-DRA, TNFSF12, EGF, INFG, and IL-18 in NPC patients vs. HCs (p < 0.05), with higher choroid plexus volumes correlating with IL-18 levels (ρ = 0.71, p = 0.047). Conclusions: The choroid plexus may play a critical role in NPC neuropathogenesis and serve as a novel biomarker for monitoring neurodegenerative and inflammatory processes in NPC.

Plasma and CSF neurofilament light chain distinguish neurodegenerative from primary psychiatric conditions in a clinical setting.

Alzheimer's & Dementia : The Journal Of The Alzheimer's Association • August 12, 2024

Dhamidhu Eratne, Matthew J Kang, Courtney Lewis, Christa Dang, Charles Malpas, Michael Keem, Jasleen Grewal, Vladimir Marinov, Amy Coe, Cath Kaylor Hughes, Thomas Borchard, Chhoa Keng Hong, Alexandra Waxmann, Burcu Saglam, Tomas Kalincik, Richard Kanaan, Wendy Kelso, Andrew Evans, Sarah Farrand, Samantha Loi, Mark Walterfang, Christiane Stehmann, Qiao-xin Li, Steven Collins, Colin Masters, Alexander Santillo, Henrik Zetterberg, Kaj Blennow, Samuel Berkovic, Dennis Velakoulis

Background: People with neurodegenerative disorders (ND) frequently face diagnostic delay and misdiagnosis. We investigated blood and cerebrospinal fluid (CSF) neurofilament light chain (NfL) to distinguish ND from primary psychiatric disorders (PPD), a common challenge in clinical settings. Methods: Plasma and CSF NfL levels were measured and compared between groups, adjusting for age, sex, and weight. Results: A total of 337 participants were included: 136 ND, 77 PPD, and 124 Controls. Plasma NfL was 2.5-fold elevated in ND compared to PPD and had strong diagnostic performance (area under the curve, [AUC]: 0.86, 81%/85% specificity/sensitivity) that was comparable to CSF NfL (2-fold elevated, AUC: 0.89, 95%/71% specificity/sensitivity). Diagnostic performance was especially strong in younger people (40- < 60 years). Additional findings were cutoffs optimized for sensitivity and specificity, and issues important for future clinical translation. Conclusions: This study adds important evidence for a simple blood-based biomarker to assist as a screening test for neurodegeneration and distinction from PPD, in clinical settings. Conclusions: NfL levels were significantly higher in ND versus PPD. Plasma NfL showed strong diagnostic performance, comparable to CSF NfL, to distinguish ND from PPD. Diagnostic performance was higher in younger people, where diagnostic challenges are greater. Further research is needed on analytical and reference range factors, for clinical translation. These findings support a simple screening blood test for neurodegeneration.

Clinical Trials

1 total

Complement Activation in the Lysosomal Storage Disorders

Withdrawn

The lysosomal storage disorders (LSDs) are monogenic disorders associated with inflammation affecting multiple organs, and early death. Few treatments are available that can modify the disease course, and there is an urgent need to identify new steps in pathogenesis that can be targeted therapeutically. The complement system is novel and highly plausible as a primary driver of inflammation and cellular injury in the LSDs. This study assesses the complement activation state in patients with Fabry disease (FD), Gaucher disease (GD) and Niemann-Pick disease, type C (NPC), with comparison to healthy controls. This has the potential for immense clinical benefit through targeted complement inhibition across the full spectrum of lysosomal storage disorders, in which key pathophysiological processes including the inflammatory response to lysosomally 'stored' materials are shared.

Frequently Asked Questions

What services does Dr Mark A. Walterfang offer?
Dr Walterfang is a neurologist with a focus on movement disorders, dementia (including Alzheimer’s and frontotemporal dementia), and related conditions. His listed services include diagnosis, assessment, and management of various neurological and psychiatric conditions.
Which conditions does he treat?
He treats a wide range of disorders such as dementia, Huntington disease, Parkinson’s disease, schizophrenia, various seizure disorders, and several rare or complex neurology and movement disorders listed in his practice profile.
How do I make an appointment?
To book, contact the clinic in Parkville, VIC 3052, Australia. The profile notes he runs a medical practice there and is available for patient appointments.
What should I bring to my first visit?
For a first visit, bring any medical records or imaging related to your neurological or psychiatric condition, a list of medications, and any questions you have about your symptoms.
Is this clinician able to manage both neurological and psychiatric conditions?
Yes. Dr Walterfang has training in neurology and psychiatry and has experience with conditions that overlap between neurological and psychiatric care.
Where is the clinic located?
The practice is in Parkville, Victoria, Australia. Please check the exact address when you contact the clinic to book.

Memberships

  • Fellow, Royal Australian and New Zealand College of Psychiatrists (FRANZCP)
  • Faculty of Consultation-Liaison Psychiatry (Australia/NZ)
  • Australian Medical Association (AMA)
  • International Neuropsychiatric Association
  • American Neuropsychiatric Association
  • British Neuropsychiatric Association
  • Society for the Study of Inborn Errors of Metabolism (SSIEM)
  • Society for Inborn Metabolic Diseases
  • Human Genetics Society of Australasia (HGSA)
  • Australasian Society of Inborn Errors of Metabolism (ASIEM)
  • Movement Disorders Society (MDS)
  • International Brain Injury Association (IBIA)
  • Australian & New Zealand Association of Psychiatry, Psychology and Law (ANZAPPL)
  • Medicolegal Society of Victoria (MLSV)