Dr Emily
Sullivan

Mastocytosis

Cutaneous and systemic mast cell disease

Mastocytosis encompasses a spectrum of disorders characterised by abnormal accumulation of clonal mast cells in one or more organs, most commonly the skin and bone marrow. It ranges from cutaneous mastocytosis — predominantly a disease of childhood — to systemic forms that may involve the bone marrow, liver, spleen, and gastrointestinal tract.

Systemic mastocytosis (SM) is driven by activating mutations in KIT and is classified according to the WHO framework. Clinical manifestations result from mast cell mediator release (flushing, anaphylaxis, gastrointestinal symptoms) and/or organ infiltration.

Management involves a multidisciplinary approach with haematology and gastroenterology where appropriate, alongside anaphylaxis risk management. Therapy for advanced disease is largely facilitated by haematology.

→ ASCIA patient information: Mastocytosis

Immunodeficiency

Primary and secondary immunodeficiency disorders

Immunodeficiency disorders encompass a broad range of conditions where the immune system fails to mount adequate defences against infection or malignancy. Primary immunodeficiencies (PIDs) are genetic or developmental disorders of the immune system, while secondary immunodeficiencies arise from external factors such as medications, malignancy, or systemic illness.

Common variable immunodeficiency (CVID) is the most frequently diagnosed symptomatic primary antibody deficiency in adults, characterised by markedly reduced serum immunoglobulins, impaired vaccine responses, and susceptibility to recurrent bacterial infections, autoimmune complications, and inflammatory bowel disease. Early diagnosis and immunoglobulin replacement therapy are central to preventing end-organ damage.

Dr Sullivan has a particular interest in the clinical evaluation of immunodeficiency, including complex presentations, unusual infectious complications, and the interface between immunodeficiency and autoimmunity.

→ ASCIA patient information: Immunodeficiency

HIV & Immunology

HIV and complex immunological presentations

HIV infection remains a significant cause of secondary immunodeficiency in Australia. Modern antiretroviral therapy (ART) has transformed HIV into a manageable chronic condition for most people living with HIV. Complex management situations still arise, including multidrug resistance, tolerability challenges, and drug–drug interactions.

Dr Sullivan has experience across HIV and immunology at major tertiary centres, including complex ART management and the immunological complications of long-term HIV infection. She has participated as a sub-investigator in multiple Phase 3 HIV treatment trials. Complex HIV management is best approached as part of a multidisciplinary team, with immune reconstitution inflammatory syndrome (IRIS) managed in the tertiary hospital setting.

This service is available to treating clinicians for complex HIV immunological questions and specialist input.

Autoimmune Conditions

Systemic autoimmunity and immune-mediated disorders

Systemic autoimmune conditions represent a diverse group of disorders in which the immune system erroneously targets host tissues. Clinical immunologists play a key role in the evaluation, diagnosis, and management of these conditions — particularly where diagnostic uncertainty exists, where presentations are atypical, or where immunomodulatory treatment carries significant risk.

Dr Sullivan has a particular research and clinical interest in IgG4-related disease (IgG4-RD), a fibroinflammatory condition that can affect multiple organ systems. She has conducted research in this area and presented at national and international conferences. Other areas of interest include autoimmune encephalitis, autoimmune cytopenias, lupus, Sjögren's syndrome, inflammatory myopathy, vasculitis, and the immunological complications of immune checkpoint inhibitor therapy.

Allergy & Anaphylaxis

IgE-mediated allergic disease, anaphylaxis, and allergen immunotherapy

Allergic diseases affect a significant proportion of the Australian population and encompass a spectrum from mild environmental sensitisation to life-threatening anaphylaxis. IgE-mediated allergic conditions include food allergy, venom allergy, latex allergy, allergic rhinitis, asthma, and atopic dermatitis — conditions that often co-exist and require a coordinated management approach.

Anaphylaxis investigation and risk stratification are central to allergy specialist practice. Establishing the causative trigger, assessing cofactors, and providing a comprehensive emergency plan are essential components of management. For appropriate patients, allergen immunotherapy (subcutaneous or sublingual) offers disease-modifying treatment for venom and aeroallergen allergy.

→ ASCIA patient information: Anaphylaxis

Angioedema

Hereditary, acquired, and idiopathic angioedema

Angioedema is the sudden, localised swelling of the deep dermis, subcutaneous tissue, or mucous membranes, caused by transient vascular leakage. It may occur with urticaria (most commonly, as part of allergic reactions or chronic urticaria) or without urticaria — the latter category being particularly important to investigate, as the underlying mechanisms and treatments differ substantially.

Hereditary angioedema (HAE) is a rare, life-threatening condition caused by C1-inhibitor deficiency or dysfunction. Attacks are unpredictable and can involve the larynx, posing a risk of asphyxiation. ACE inhibitor-induced angioedema is an important and underrecognised entity. Acquired C1-inhibitor deficiency may be associated with lymphoproliferative disease or autoimmunity.

→ ASCIA patient information: Angioedema

Atopic Dermatitis

Moderate-to-severe eczema and atopic disease

Atopic dermatitis (eczema) is a chronic, relapsing inflammatory skin condition characterised by intense pruritus, skin barrier dysfunction, and immune dysregulation. It is the most common chronic inflammatory skin disease and often represents the first step in the atopic march, with many patients also developing allergic rhinitis and asthma.

For patients with moderate-to-severe disease that is inadequately controlled with topical therapies, the management landscape has transformed with the availability of targeted biologics for appropriate patients. Clinical immunologists play an important role in the assessment of atopic dermatitis in the context of broader atopic disease, and evaluation for underlying immunodeficiency when presentations are severe or atypical.

→ ASCIA patient information: Eczema (Atopic Dermatitis)