Review spotlights adrenal dysfunction in critically ill foals

A newly published review is putting fresh attention on a familiar but still unsettled problem in equine critical care: hypothalamic-pituitary-adrenal axis dysfunction in critically ill foals and horses. In Veterinary Clinics of North America: Equine Practice, Katarzyna Dembek summarizes the state of evidence around critical illness-related corticosteroid insufficiency, or CIRCI, arguing that inadequate cortisol responses during sepsis and endotoxemia may be contributing to poor outcomes, even as diagnosis remains inconsistent in practice. The article was published September 16, 2026. (madbarn.com)

The topic isn't new, but it has been hard to operationalize at the bedside. Earlier equine literature described transient HPA-axis dysfunction in hospitalized neonatal foals and linked it with greater illness severity and lower survival, while later work suggested relative adrenal insufficiency may be common in septic foals. At the same time, broader sepsis reviews have emphasized how limited the field's evidence base remains, particularly in adult horses, and have cautioned that there still isn't enough evidence to make routine corticosteroid recommendations in septic equine patients. (pubmed.ncbi.nlm.nih.gov)

Dembek's review appears aimed at that gap between pathophysiology and clinical decision-making. Based on the abstract and publication details available online, the paper frames CIRCI as a transient dysfunction of the HPA axis that leads to inadequate cortisol activity relative to the severity of illness. It highlights a core challenge for clinicians: basal cortisol can be misleading, because critically ill patients may show normal or even elevated concentrations while still having an inadequate stress response. The review therefore points toward dynamic adrenal testing and faster hormone measurement, including point-of-care assays, as possible ways to improve identification of the subset of foals and horses most likely to benefit from treatment. (madbarn.com)

That emphasis aligns with the author's prior research trajectory. Dembek has previously published on HPA-axis dysfunction in neonatal foals, the renin-angiotensin-aldosterone system in hospitalized newborn foals, steroid responses in critically ill equine neonates, and vasopressin stimulation testing in foals, all of which support the idea that endocrine responses in equine sepsis are more complex than a single cortisol value can capture. Inference: this new review likely serves as a synthesis of that body of work and a push toward more clinically usable testing strategies. (pubmed.ncbi.nlm.nih.gov)

There is also an industry angle worth noting. The publication disclosure states that Dembek has served as a compensated equine endocrinology consultant for Zomedica, which markets equine ACTH and cortisol assays on its TRUFORMA platform. Zomedica says its platform offers in-clinic equine cortisol and endogenous ACTH testing, which is relevant because the review specifically highlights point-of-care hormone testing as a promising development. That doesn't negate the clinical value of the review, but it is context veterinary professionals will want to keep in mind when evaluating discussion of emerging diagnostics. (madbarn.com)

Why it matters: For equine practitioners, the review reinforces a central tension in emergency and neonatal medicine: some foals and horses may have clinically meaningful adrenal dysfunction during sepsis or endotoxemia, but the profession still lacks standardized, validated criteria to diagnose CIRCI confidently and treat it consistently. Existing guidance suggests physiologic-dose corticosteroids may help selected hypotensive patients that remain unstable despite fluids and vasopressors, yet warns against indiscriminate use, especially given the lack of controlled clinical trials and the risk of overtreating patients whose cortisol signaling is adequate. Better point-of-care testing could shorten turnaround times and sharpen decision-making, but adoption will depend on independent validation, reference intervals, and proof that test-guided treatment improves outcomes. (science.unimelb.edu.au)

For hospitals managing neonatal foal sepsis, the practical implication is that endocrine dysfunction may deserve a more explicit place in shock workups and treatment algorithms, particularly when hypotension, hypoglycemia, or poor pressor response persist. For adult horse practice, the review may help keep CIRCI on the differential in severe endotoxemia and sepsis, while also reminding clinicians that evidence is thinner in mature horses than in foals. In both settings, the paper supports a more tailored approach rather than a reflexive one. (pmc.ncbi.nlm.nih.gov)

What to watch: The next meaningful step will be prospective studies that test whether dynamic or point-of-care endocrine assessment changes case management or survival, along with clearer consensus on which foals and horses should receive low-dose hydrocortisone, at what dose, and for how long. (madbarn.com)