Welcome to the premiere of Across the Rheum, the official podcast of Rheum Connect, where cutting-edge science meets real-world clinical insight in rheumatology. Hosted by renowned rheumatologist Dr. Sergio Schwartzman, this new educational podcast launches with a three-part series exploring The Interleukin-23 (IL-23) Paradigm in Psoriatic Arthritis.

In Episode 1, the series sets the foundation with an in-depth discussion of IL-23 immunology and its role in the pathophysiology of psoriatic disease. Joined by expert guests Jessica Farrell, PharmD, and Dr. Monica Schwarzman, listeners gain a structured understanding of the IL-23/Th17 pathway, cytokine signaling, and how these mechanisms translate into targeted therapeutic strategies for psoriatic arthritis and related immune-mediated diseases.

Designed for rheumatologists, advanced practice providers, pharmacists, and clinicians involved in inflammatory arthritis care, this episode examines why IL-23 has emerged as a critical therapeutic target, the scientific rationale behind selective inhibition, and how evolving immunologic insights are shaping modern treatment decisions. The discussion also highlights key distinctions between IL-23– and IL-17–driven disease, implications for axial involvement, and the future of precision therapy in psoriatic arthritis.

This episode is cross-hosted on Arthros and the RhAPPcast, the official podcast of Rheumatology Advanced Practice Providers, with sincere thanks to RhAPP for their continued partnership. Educational support for this activity is provided by Johnson & Johnson.

Subscribe to Across the Rheum to continue the series in Episode 2, where the conversation shifts to a detailed review of currently available IL-23 inhibitors, clinical trial data, and practical positioning in today’s rheumatology treatment landscape.

In this episode of RhAPPcast, host Amanda Mixon, President of RhAPP, is joined by pediatric rheumatology specialist and RhAPP board member Brandon Ko to spotlight hypophosphatasia (HPP) in children—an underrecognized inherited metabolic bone disorder that is frequently missed in clinical practice. The conversation reviews perinatal, infantile, and childhood-onset HPP, highlights subtle early warning signs like failure to thrive, delayed milestones, craniosynostosis, bone pain, recurrent fractures, and premature loss of primary teeth with intact roots, and explains why persistently low alkaline phosphatase (ALP) is a key diagnostic red flag. Designed for rheumatology APPs and primary care clinicians, this episode offers practical steps to improve recognition, differentiate HPP from conditions like JIA and pain amplification syndromes, and support earlier evaluation and referral for appropriate testing.

In this episode of RhAPPcast, host Amanda Mixon, President of RhAPP, is joined by rheumatology PA Audrey Gibson for an in-depth discussion on IL-23 inhibitors and what differentiates them in real-world rheumatology practice. The conversation reviews the IL-23/Th17 pathway, current approved IL-23 inhibitors for psoriatic arthritis, and key considerations around efficacy, safety, durability, and patient selection, including comorbid psoriasis and inflammatory bowel disease. Designed for rheumatology APPs, this episode also explores practical expectations for treatment response, emerging clinical trial data, and how IL-23 inhibitors fit into a domain-based approach to managing psoriatic disease.

In this FAQ, Brandon Ko, APRN, a pediatric rheumatology nurse practitioner and RhAPP Pediatric Chair, provides a practical overview of hypophosphatasia (HPP) across the lifespan and explains why this rare inherited metabolic bone disorder is often missed in clinical practice. The discussion reviews pediatric and adult presentations of HPP, including subtle skeletal symptoms, premature tooth loss with intact roots, stress fractures, osteomalacia, and early-onset pseudogout, and highlights persistently low alkaline phosphatase as a key diagnostic red flag. Designed for APPs and clinicians, this concise video outlines when to suspect HPP, how to begin the evaluation, and why early recognition is critical in both pediatric and adult rheumatology settings.

In this journal club review, clinical pharmacist Danielle Gatti Palumbo, breaks down a March 2025 study examining how guselkumab’s unique Fc-domain interactions with CD64-positive, IL-23–producing myeloid cells enhance its potency in neutralizing IL-23 signaling. The discussion explores the immunologic role of IL-23 in inflammatory diseases such as psoriasis, psoriatic arthritis, and inflammatory bowel disease, compares Fc-domain differences between IL-23 inhibitors, and highlights key in vitro findings using flow cytometry, live-cell imaging, and co-culture assays. This concise overview helps APPs and clinicians better understand emerging mechanisms that may influence therapeutic efficacy and treatment selection in IL-23–driven inflammatory conditions.

In this focused educational video, Heather Mambretti, PA-C, a rheumatology APP with over 12 years of experience and a faculty and board member for RhAPP, explains how hypophosphatasia (HPP) is diagnosed and highlights the key laboratory markers clinicians should not overlook. The discussion reviews the hallmark finding of persistently low serum alkaline phosphatase (ALP), additional supportive labs, characteristic clinical features in adult patients, and the role of imaging and genetic testing in confirming an HPP diagnosis. Designed for APPs and clinicians, this overview emphasizes practical strategies for identifying adult-onset hypophosphatasia, differentiating it from other musculoskeletal conditions, and improving diagnostic confidence in real-world rheumatology practice.

In this video, Lindsay Tom, PA-C, takes a focused look at the emerging connection between CD64 and IL-23 across inflamed joint, skin, and gut tissue. Drawing from real-world immunology and disease-state research, she explores why this pathway matters in immune-mediated inflammatory conditions such as psoriasis, psoriatic arthritis, and inflammatory bowel disease. The discussion highlights how CD64-expressing myeloid cells may influence inflammatory signaling, how this relationship shows up differently across tissues, and why these insights are shaping the way clinicians think about disease activity and treatment selection. This concise overview offers valuable perspective for APPs and clinicians looking to better understand the immunologic drivers behind these complex conditions and the therapies designed to target them. Visit the RhAPP Content Rheum or the RhAPP ACE 2.0 app for more rheumatology education.

In this educational rheumatology video, physician assistant Lindsay Tom, PA-C, from the Northern Virginia Center for Arthritis, provides a clear and clinically relevant overview of CD64, also known as FC gamma receptor I, and its role in immune system function. The discussion explores how CD64 is expressed on myeloid lineage cells such as monocytes, macrophages, and dendritic cells, and how it contributes to innate immunity by binding IgG antibodies and triggering phagocytosis and pro-inflammatory cytokine release, including TNF-α. The video also explains CD64’s role in adaptive immunity through antigen processing and presentation to T cells, leading to immune activation and immunologic memory. Importantly, this overview highlights how dysregulated or excessive CD64 activation may contribute to chronic inflammation, tissue damage, and antibody-mediated autoimmune diseases—making it a key concept for clinicians managing inflammatory and rheumatic conditions. This video is part of ongoing educational content designed for advanced practice providers seeking a deeper understanding of immunologic pathways relevant to rheumatology care.