“The immune system generally likes to be a well-balanced machine. It’s kind of like Goldilocks — too much is no good, too little is no good, and it’s finding that balance.”  Dr. Vy Kim

Tregs have been called therapists, peacekeepers, and now—thanks to this year’s Nobel Prize—front-page immunology. Dr. Vy Kim joins Dr. Mariam Hanna to unpack why these cells might hold the key to everything from tolerance to therapy response, and what allergists should be watching for next.

• How Tregs bridge central and peripheral tolerance—and why that matters in allergy.
• What their dysfunction reveals about the origins of allergic disease.
• Why allergen-specific Tregs could signal immunotherapy success.
• How far we are from clinical testing and therapeutic manipulation.
• What “Goldilocks” balance really looks like inside the immune system.
• The unanswered questions that will shape the future of Treg-based interventions.

It’s not every day the Nobel Prize lines up with what’s happening in your clinic. This is one of those days.

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Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“Don't just rely on the textbook definition of when the pollen seasons are. You need to have reliable data to know when the pollen seasons are starting, when they're ending, and when they're peaking.”  Dawn Jurgens

Allergy season may be winding down, but for allergists, the work never really stops. This is the moment between ragweed and winter — a brief respite before the cycle begins again. On this episode, Dr. Mariam Hanna is joined by Dawn Jurgens, Director of Operations and Quality Management at Aerobiology Research Laboratories. She breaks down the science behind pollen and spore counts, why forecasts matter, and how shifting seasons are changing the game for patients and clinicians alike.

• Timothy grass is the most common and potent trigger globally, while birch remains the most clinically relevant pollen in Canada. Pine releases large amounts of pollen but isn’t highly allergenic.
  
  
• Pollution and thunderstorms can make pollen more potent by breaking it apart and exposing allergenic epitopes, intensifying symptoms.
  
  
• Cross-reactivity stems from conserved epitopes, meaning patients sensitized to one pollen may react to related species — or even certain foods.
  
  
• Mold spores, especially Alternaria, Cladosporium, and Basidiospores, can mimic ragweed season and are major fall culprits.
  
  
• Canada’s pollen seasons are starting earlier than they did 30 years ago, though the fall season hasn’t yet extended.
  
  
• Simple strategies — like showering before bed, keeping windows closed, using filters, brushing pets outside, and checking reliable forecasts — can meaningfully reduce exposure.

Pollen season may be taking a break, but planning for the next wave starts now.

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Find an allergist using our helpful tool

Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“Vaccine counseling is really a team sport. — Dr. Anne Pham-Huy

Vaccines can stir anxiety for patients and confusion for clinicians, especially when biologics enter the mix. Dr. Mariam Hanna is joined by Dr. Anne Pham-Huy, clinical immunologist at CHEO, member of the Special Immunization Clinic Network, NACI member, and chair of Immunize Canada. Together, they break down the science of vaccine responses and tackle some of the trickiest questions allergists face in daily practice.

On this episode:

• The major types of vaccines — from live attenuated to mRNA — and what sets them apart.
  
  
• Why live vaccines often produce strong, durable protection, but may require caution in certain patients.
  
  
• How adult immunization is still underutilized, with gaps in boosters, pneumococcal, HPV, and influenza coverage.
  
  
• Which “special populations” need tailored vaccine strategies, including patients on immunosuppressants, transplant recipients, and those with chronic disease.
  
  
• Practical guidance on timing vaccines around biologic use and which precautions truly matter.
  
  
• When to check titers and antibody responses — and why it’s only relevant for select patient groups.
  
  
• Strategies for counselling vaccine-hesitant patients with empathy, focusing on disease risk and building trust.
  
  
• What’s next: combination mRNA vaccines and nirsevimab for RSV prevention in infants.

The questions are simple — are they vaccinated, special, or special enough — but the answers matter.

Visit the Canadian Society of Allergy and Clinical Immunology

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Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“Atopic dermatitis is not just about what you see on the skin. It's about what the patient's experiencing.” Dr. Melinda Gooderham

Eczema care has become a world of creams, cleansers, oils, and myths — but what actually works? Dr. Mariam Hanna is joined by Dr. Melinda Gooderham, assistant professor at Queen’s University and consultant physician at the Peterborough Regional Health Centre. As principal investigator for more than 250 clinical trials, Dr. Gooderham brings both evidence and practical wisdom to the table.

On this episode, they explore:

• Why barrier repair remains the cornerstone of therapy, and how humectants, emollients, and occlusives play distinct roles
  
  
• The evidence behind natural oils (and why olive oil is out while coconut, sunflower seed oil, and shea butter may have a place)
  
  
• Bathing basics: frequency, water temperature, and whether bleach baths still matter
  
  
• How to choose topical steroid potency and when to pivot toward non-steroidal options
  
  
• The promise of newer agents: calcineurin inhibitors, PDE-4 inhibitors like roflumilast, and topical JAK inhibitors
  
  
• When to escalate to systemic therapy, with itch and quality of life as key markers

Eczema may be complex and misunderstood, but Dr. Gooderham reminds us that consistent barrier care, adequate product use, and asking the right questions about itch can simplify management and improve patient outcomes.

Visit the Canadian Society of Allergy and Clinical Immunology

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Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“You will think it is mastocytosis much more often than you'll actually diagnose mastocytosis.” — Dr. Matthieu Picard

Mastocytosis is rare, complex, and often confused with other mast cell disorders. To help clinicians cut through the confusion, Dr. Mariam Hanna welcomes Dr. Mathieu Picard, allergist and clinical immunologist, who has built a dedicated practice caring for patients with mast cell diseases. Together, they explore what physicians need to know about diagnosis, monitoring, and management.

On this episode:

• Adults: Around 80% of adults with skin lesions have systemic mastocytosis, and the disease typically persists.
• Children: Pediatric cases are almost always cutaneous and often resolve by puberty.
• When to order a tryptase — and why a normal result doesn’t rule out systemic disease
• The role of KIT D816V mutation testing and why biopsy technique matters
• Key risks to monitor in indolent systemic mastocytosis: anaphylaxis, osteoporosis, and rare progression to advanced disease
• Practical tips for patient care, including venom immunotherapy considerations, osteoporosis screening, and symptom control strategies

Mastocytosis may be rare, but it doesn’t take uncommon skill to spot — just the right tools, a sharp eye, and maybe a tongue depressor scratched five times.

Visit the Canadian Society of Allergy and Clinical Immunology

Find an allergist using our helpful tool

Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“At least 60% don't respond to anything or who have been to somebody else before and they've come to me and they've tried everything and failed” — Dr. Imran Satia

Dr. Imran Satia, Respirologist and Associate Professor at McMaster University and Canada Research Chair in Chronic Cough, joins Dr. Mariam Hanna to walk clinicians through a practical, evidence-based approach to diagnosing and managing chronic cough. With decades of research and clinical experience, Dr. Satia explains how to define chronic cough and its subtypes, recognize red flags, and navigate the common — and less common — causes that keep patients coughing for years.

On this episode, you’ll hear:

• The difference between chronic cough, refractory chronic cough, and unexplained chronic cough — and why the terminology matters for treatment.
  
  
• The key investigations every patient with chronic cough should have, and how to interpret results in the context of cough hypersensitivity.
  
  
• The role and real-world value of methacholine challenge, FeNO, induced sputum, and sputum culture in refining diagnosis and guiding therapy.
  
  
• Why empiric ICS–LABA and PPI trials aren’t always the right move — and when they are.
  
  
• Management strategies for patients who don’t respond to initial treatment, starting with a low-dose morphine trial, followed by neuromodulators, speech therapy, and clinical trial options.

By the end of the episode, you’ll have a clear, step-by-step framework for assessing chronic cough, avoiding unnecessary treatments, and helping even the most refractory patients find relief.

Visit the Canadian Society of Allergy and Clinical Immunology

Find an allergist using our helpful tool

Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“Putting yourself out there online as a doctor is not easy. But staying silent while misinformation spreads—that felt worse.” —Dr. Amiirah Aujnarain

Dr. Amiirah Aujnarain has built a community of 80,000 followers by blending evidence-based allergy education with a candid, human presence online. On this episode of The Allergist, she joins Dr. Mariam Hanna to examine how social media is shaping allergy conversations—sometimes for better, sometimes for worse.

From Benadryl challenges to dupilumab searches on TikTok, patients are turning to social media for answers long before they see a specialist. Dr. Aujnarain shares how she’s meeting them where they are, and why she sees it as both a responsibility and a creative outlet.

This episode covers:

• How allergy misinformation spreads on social media—and what physicians can do about it
  
  
• Why patients are using TikTok like Google, and how that’s changing referral patterns
  
  
• What physicians should consider before joining social media, including boundary-setting, time commitment, and emotional labour
  
  
• The upside of being a visible, human face of allergy care—and the backlash that can come with it

Whether you’re thinking about launching your own account or simply wondering how your patients are being influenced online, this conversation is an honest look at the power and pitfalls of digital engagement.

Visit the Canadian Society of Allergy and Clinical Immunology

Find an allergist using our helpful tool

Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“I can’t think of any medical condition where you can have this type of fry but not that type of fry.” —Dr. Vish Avanashi

Pediatric gastroenterologist Dr. Vish Avinashi joins Dr. Mariam Hanna for an episode that jumps head first into the overlapping world of allergy and GI. From ARFID to EOE, they talk about the murky middle ground where food fears, immune triggers, and gut symptoms collide—and how allergists can better navigate it all with the help of a friendly gastroenterologist.

• How to recognize ARFID and why history, not testing, is your best diagnostic tool
• Common pitfalls in celiac diagnosis—and why a positive TTG doesn’t always mean celiac
• New, and surprising treatments for IBS, including nerve stimulation and gut-directed hypnotherapy
• What the microbiome research does—and doesn’t—tell us
• Understanding fibrosis in EOE and when to skip dietary elimination

When it comes to navigating the overlap between allergy and GI, remember: always learning, always listening, always befriending a gastroenterologist.

Visit the Canadian Society of Allergy and Clinical Immunology

Find an allergist using our helpful tool

Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“They may worsen, they may improve, or they might not change at all, and it really is patient-dependent.” —Dr. Lana Rosenfield

On this episode of The Allergist, Dr. Mariam Hanna welcomes Dr. Lana Rosenfield to unpack the complexities of managing allergic conditions during pregnancy and postpartum. With hormones shifting, the immune system recalibrating, and anxiety about medication safety running high, allergic disease can be especially tricky to manage during this time. Dr. Rosenfield offers practical insights for clinicians supporting pregnant patients with conditions like asthma, rhinitis, chronic urticaria, and food allergy, while navigating a landscape of limited data and heightened patient concerns.

On this episode:

• How the maternal immune system changes during pregnancy—and why it may exacerbate allergic conditions
  
  
• Safe options for managing allergic rhinitis, including which medications to avoid
  
  
• Asthma in pregnancy: monitoring frequency, preferred inhalers, and why under-treatment is riskier than treatment
  
  
• Atopic dermatitis: mimics to watch for, which topicals are safe, and what we know (or don’t) about dupilumab
  
  
• Managing chronic urticaria with second-generation antihistamines and omalizumab
  
  
• Food allergy and anaphylaxis: fetal risks, symptom variations, and why epinephrine remains essential
  
  
• What to do with patients already on immunotherapy, and why it should never be initiated during pregnancy
  
  
• Biologics and breastfeeding: limited evidence, but emerging reassurance
  
  
• Preconception counselling and postpartum care: optimizing control while minimizing risk
  
  

Dr. Rosenfield emphasizes shared decision-making, lowest effective dosing, and the clinical resources she trusts when evidence is limited. It’s a thoughtful and clinically grounded conversation to support allergists managing allergic conditions through pregnancy and beyond.

Visit the Canadian Society of Allergy and Clinical Immunology

Find an allergist using our helpful tool

Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions

“Have a high clinical suspicion for contact allergens or irritants in anyone presenting with eczematous rash.” —Dr. Rebecca Pratt

Creams that sting and rashes that won’t quit —welcome to the complex world of contact dermatitis. Dr. Rebecca Pratt joins Dr. Mariam Hanna to unpack why diagnosing and managing this condition is anything but straightforward.

Dr. Pratt is an allergist and clinical immunologist in St. Catharines, Ontario, with a passion for dermatoimmunopathology and practical tools that empower patients. She breaks down when to patch test, what to suspect, and how to help patients take control.

On this episode:

• Why 80% of contact dermatitis cases are irritant—not allergic
  
  
• Clues that point to allergic contact dermatitis, especially in recurring facial, hand, or foot rashes
  
  
• How to approach patch testing in adults and kids, including when immunosuppressants or UV exposure may interfere
  
  
• What to do when results are negative—and why that still matters
  
  
• The reality of managing allergens found in foods, not just topicals
  
  
• Why there’s no one-size-fits-all answer to the sunscreen question—and how physical blockers stack up

There may be no cure for contact allergy, but there’s power in knowing what to avoid.

Visit the Canadian Society of Allergy and Clinical Immunology

Find an allergist using our helpful tool

Find Dr. Hanna on X, previously Twitter, @PedsAllergyDoc or CSACI @CSACI_ca

The Allergist is produced for CSACI by PodCraft Productions