Generalized steatitis in horses

This is a fairly rare condition of horses and should be considered in horses with fever and poor doing without other known causes. Following this recent case report below is a summary of 20 cases including helpful diagnostic information: the presence of hyperechoic fat layers.
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Generalized steatitis in a miniature horse filly with laminitis and a positive outcome at 18-month follow-up

Can Vet J. 2025 Dec 1;66(12):1292-1296. eCollection 2025 Dec.
Authors
Acacia Johnson 1 , Bruno Karam 1 , Olivia Schroeder 1 , Lauren McKaig 1 , Kimberly Loesch 1
Affiliation

1 Pilchuck Veterinary Hospital, Snohomish, Washington, USA (Johnson, Karam, McKaig, Loesch); Northwest Equine Veterinary Associates, Black Diamond, Washington, USA (Schroeder).

PMID: 41584239
PMCID: PMC12825629 (available on 2026-03-01)

Abstract
in English, French

A 12-month-old miniature horse filly was presented because of laminitis, suspected lymphangitis, and pyrexia. Although the filly’s initial physical examination and diagnostic tests suggested an infectious etiology, ultrasonographic findings were suspicious for generalized steatitis. This was confirmed via histopathology. The filly experienced full recovery with continued resolution of clinical signs at 18 mo after presentation. This case included aspects similar to those of previously reported clinical presentations, as well as long-term follow-up in a breed that is not overrepresented, providing additional documentation of an uncommon condition in a miniature horse in North America. Key clinical message: Generalized steatitis is an uncommon condition in equids in North America. This case provided an example to aid in recognition, diagnosis, and treatment associated with a favorable outcome.
Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.

11 references

From an EVJ article:
Yellow fat disease (steatitis) in 20 equids: Description of clinical and
ultrasonographic findings

E. Paulussen ,L. Lefere, C. Bauwens, B. Broux ,D.DeClercq andG.vanLoon*
Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke,
Belgium.
Keywords: horse; yellow fat disease; steatitis; ultrasonography

Summary
Diagnosis of steatitis can be challenging due to nonspecific
clinical signs and ultrasonography might be a useful aid
for making a diagnosis. The objective of this retrospective
clinical case study was to describe history, clinical signs,
ultrasonographic findings, treatment and outcome in equids
with steatitis. The medical records of all equids presented to the
DepartmentofLargeAnimalInternalMedicine,GhentUniversity
between January 2008 and December 2015 were reviewed
retrospectively to identify horses suffering from steatitis. A total of
20 cases with steatitis were reviewed. History included dullness,
recumbency, decreased appetite and weight loss. Fever,
ventral oedema, stiff/painful gait and a painful neck were
found. Low haematocrit, low vitamin E and selenium and
increased levels of creatinine kinase and particularly lactate
dehydrogenase werealmostconsistent findings. On ultrasound,
ventral oedema was found. Ventral extraperitoneal, perirenal,
mesenteric, coronary and caudal mediastinal fat showed
homogenously increased echogenicity. The ventral
extraperitoneal fat in particular was surrounded by oedema or
free fluid. Increased amounts of abdominal, thoracic and
pericardial fluid were often found. Fat biopsies were takenin the
neck, or from the ventral extraperitoneal fat in the ventral flank.
Steatitis was confirmed in all horses where a fat biopsy
was taken (n = 13). Treatment consisted of selenium
and vitamin E (intramuscular injection followed by oral
treatment) supplementation and anti-inflammatory treatment
(dexamethasone or prednisolone parenteral or oral) for at least
1–4 weeks. A total of 15 animals (75%) survived. Full recovery
took about 2–6 months. In conclusion, steatitis is an uncommon
disease in young horses usually seen during winter. It may be
underdiagnosed because of nonspecific clinical signs.
Ultrasonography is a useful aid for the diagnosis of yellow fat
disease based upon the increased echogenicity of ventral
extraperitoneal, perirenal, mesenteric, coronary and caudal
mediastinalfatandincreasedamountofsurroundingfluid.

• This topic was modified 1 month ago by Robert Oglesby DVM.