Table of Content

Current Issue

Spring/Summer 2025, Vol. 32 No. 1

Hong Kong J. Dermatol. Venereol. (2025) 32, 81-83


Reports on Scientific Meetings

EADV CongreHong Kong Dermatology Symposium 2024

Reported by MYK Chan 陳伊琪, LH Chan 陳樂軒, TH Chan 陳子浩, PY Leung 梁沛怡

Date:   3 November 2024
Venue:   Show Auditorium, Postgraduate Education Centre, Jockey Club Building, Prince of Wales Hospital, Hong Kong
Organiser:   Hong Kong Dermatology Foundation; Department of Anatomical & Cellular Pathology, CUHK; Hong Kong Paediatric & Adolescent Dermatology Society; Hong Kong College of Paediatric Nursing

Use of JAKi/Biologics in special populations with atopic dermatitis

Speaker: DYK Lai
Private Dermatologist, Hong Kong SAR

Systemic treatment is often indicated for patients with moderate to severe atopic dermatitis. However, certain populations, including the elderly, individuals with past or ongoing infections, those with a history of malignancy, and pregnant individuals, may be contraindicated for conventional immunosuppressive drugs such as methotrexate, cyclosporine, and azathioprine. In this context, biologics like anti IL-4/13 monoclonal antibodies (e.g. dupilumab) and JAK inhibitors (e.g. abrocitinib, upadacitinib) have emerged as novel treatments for moderate to severe atopic dermatitis. This lecture reviews the literature on the use of these agents in special populations affected by atopic dermatitis.

The relationship between the targeted therapies and various infections has been highlighted, with herpes zoster identified as a common side effect of JAK inhibitors. As such, the recombinant zoster vaccine should be considered before initiating treatment with JAK-1 inhibitors. On the other hand, dupilumab has been shown to reduce the risk of eczema herpeticum, likely due to its ability to improve the severity of atopic dermatitis.

Dupilumab is generally considered safe for patients with chronic hepatitis B. Current evidence supports screening for latent tuberculosis before starting biologic therapy. The choice and timing of chemoprophylaxis should align with relevant national and international guidelines.

Although dupilumab seems safe for patients with a history of malignancy, it is essential to exclude the possibility of cutaneous T-cell lymphoma prior to its initiation. Data on the use of dupilumab during pregnancy is limited, but maternal exposure does not appear to be associated with significant risks or complications. Therefore, it is suggested that dupilumab may be safe for females of reproductive age if discontinued upon confirming pregnancy status.

Dupilumab may be considered for older adults (aged ≥65 years) and individuals with multiple comorbidities. It has also been shown to be safe for use in people living with HIV, as it does not significantly affect viral load or CD4 counts. However, conjunctivitis is a well-known adverse effect of dupilumab, which may lead to treatment discontinuation, especially in individuals with a prior history of conjunctivitis.

The following factors should be considered when deciding between anti-IL-4/13 monoclonal antibodies (e.g. dupilumab) and JAK inhibitors for patients with atopic dermatitis.

Factors favouring monoclonal antibody targeting the IL-4/13 axis (e.g. dupilumab):

Factors favouring JAK inhibitors:

The decision regarding targeted therapy for atopic dermatitis should be personalised for each individual, with the hope that biomarkers will become available to inform this decision.

Learning points:
Biologics like dupilumab (an anti-IL-4/13 monoclonal antibody) and JAK inhibitors offer promising alternatives to conventional immunosuppressive drug for special populations with moderate to severe atopic dermatitis. Dupilumab is generally considered safe for patients with chronic hepatitis B and those with a history of malignancy, provided that certain precautions are taken. Additionally, screening for latent tuberculosis is recommended before initiating therapy. Factors influencing the choice between anti-IL-4/13 monoclonal antibodies and JAK inhibitors include patient age, cardiovascular history, risk of infections, and specific disease phenotypes.

Microbiome diagnostics and therapeutics in atopic dermatitis

Speaker: S Loo
CUHK Medical Centre, Hong Kong SAR

Dr. Steven Loo delivered a comprehensive lecture on the role of the gut microbiome in atopic dermatitis (AD), highlighting recent advancements in microbiome diagnostics and therapeutics. He discussed the Gene-Environment Interaction and its impact on the microbiome's composition, influencing conditions such as atopic dermatitis. The lecture emphasized the Gut-Skin Axis, explaining how gut dysbiosis (an imbalance in the gut microbiota) could contribute to the development of AD.

Dr. Loo presented data from studies showing that infants with AD had reduced microbial diversity, with lower levels of beneficial bacteria like Bifidobacterium and higher concentrations of Escherichia coli, which may increase eczema susceptibility. He also discussed the Microbiome Dysbiosis Index (MDI), a novel diagnostic tool for assessing gut health and its application in personalised AD treatment.

Therapeutic strategies included the use of probiotics, prebiotics, and fecal microbiota transplantation (FMT) to restore gut balance. Probiotics, especially Lactobacillus rhamnosus, have been shown to reduce atopic disease risk in high-risk infants, as demonstrated in various studies. Dr. Loo highlighted that personalised microbiome-based therapies could become the future of AD treatment, supported by advancements in AI and big data analytics for precision diagnostics.

Learning points:
Personalised microbiome-based diagnostics and interventions, such as probiotics, show promise in managing atopic dermatitis and preventing its onset in high-risk populations.

Update on melasma

Speaker: SW Chan
Private Dermatologist, Hong Kong SAR

Melasma is a chronic skin condition characterised by localised hyperpigmentation. Its causes include genetic predisposition, UV radiation exposure, visible light exposure and hormonal influences. It predominantly affects young to middle aged women with skin type III-IV. It can significantly impact quality of life. General measures for treatment include sun protection, cessation of hormonal treatment and comestic camouflage. Topical treatments include azelaic acid, ascorbic acid as well as a combination of hydroquinone, retinoid and steroid. Systemic treatments are tranexamic acid, pycnogenol, glutathione, lycopene-rich tomato extract and polypodium leucotomos. Second line treatments are chemical peels, platelet rich plasma. Intense pulsed light, various lasers and radiofrequency ablation are also effective treatment options. Despite various treatment, there is no cure and it frequently recurs. Currently, there is no universal quideline or consensus on its treatment.

Learning points:
Prevention by sun avoidance is the main stay of management for melasma. Realistic expectation should be set with patient before starting treatment.

Update of severe cutaneous adverse reactions (SCAR)

Speaker: MH Chung
Department of Dermatology, Chang Gung Memorial Hospital, Taiwan

This lecture summarises different cutaneous manifestation of SCAR and most common culprit drugs related to Seven Johnson Syndrome (SJS) and toxic epidermal necrosis (TEN). New medication such as immune check point inhibitor is an emerging challenge of drug eruption. It explains the mechanistic models for T cell recognition and activation and systemic factors contribution to SCAR. HLA risk allele linked to SCAR, factors that participate in and facilitate SCAR, prognostic and predictive factor for SCAR are also mentioned. Moreover, it summarises the management and the therapeutic mechanism for SCAR.

Learning points:
An early withdrawal of culprit drugs and an early intervention to stop immune reaction may reduce patient morbidity and mortality. Specific biologics and small molecular drug therapy may be potential to be applied for the management of SCAR in the future.