Focal Intestinal Lipogranulomatous Lymphangitis in 6 Dogs (2008–2011)

Abstract

BackgroundLipogranulomatous lymphangitis is inflammation of the intestinal lymphatic vessels and surrounding tissues caused by chronic leakage of lipid‐laden chyle. Grossly, lipogranulomas are typically disseminated small masses on the serosa and surrounding lymphatic vessels and consist of epithelioid macrophages, multinucleated giant cells, and cholesterol. Lipogranulomatous lymphangitis is occasionally seen in patients with lymphangiectasia and protein‐losing enteropathy (PLE).ObjectivesTo characterize the historical features, clinical signs, treatment, histopathology, and outcome of dogs with focal lipogranulomatous lymphangitis.AnimalsSix dogs with ultrasonographic evidence of focal, regional small intestinal masses, often with involvement of the adjacent mesentery, and a diagnosis of focal lipogranulomatous lymphangitis based on histopathology of biopsied masses.ResultsThe median age of dogs was 6.9 years (range 3–10 years). All dogs had total protein, globulin, and albumin concentrations within the reference range at initial presentation and had intestinal masses identified on abdominal ultrasound examination. Histopathologic evaluation of lesions identified severe mural and mesenteric lipogranulomatous lymphangitis. Lymphangiectasia was noted in 5 cases and only in sections within the mass‐like lesion; tissue without lipogranulomas had minimal lymphangiectasia, suggesting a localized phenomenon. Postoperative outcomes ranged from remission of clinical signs with no subsequent treatment for 10–12 months in 2 dogs, postoperative management with medical and nutritional management in 3 dogs, and no outcome for 1 case.Conclusions and Clinical ImportanceThis case series describes a unique mass‐like manifestation of intestinal lipogranulomatous lymphangitis and should be considered as a possible differential diagnosis in dogs with an intestinal mass.

Clinical characteristics of dogs with food‐responsive protein‐losing enteropathy

“…Considering that dogs with primary IL tend to be young and responsive to ULFD, we speculate that the dogs with FR‐PLE in our study in fact may have had primary IL even though not every responder showed lacteal dilatation on histopathology. Considering the limitations of endoscopic tissue biopsy samples for the diagnosis of IL, structural lesions might have been present in the deeper mucosa or distal jejunum, or might have been artificially altered during the collection, which may have led to an underestimation of IL . These findings are supported by the fact that the majority of the dogs in the FR‐PLE group in our study (22 of the 23, 95.7%) had intestinal hyperechoic mucosal striations.…”

Focal intestinal lipogranulomatous lymphangitis in 10 dogs

“…, Watson et al . ). Differential diagnoses usually include neoplastic and non‐neoplastic causes of intestinal masses such as infectious granulomatous disease (e.g.…”

“…, Watson et al . ). The aetiology is unclear and the prognosis is guarded (Guilford ), although long‐term remission can be achieved following surgical excision of the lesion (Watson et al .…”

“…The aetiology is unclear and the prognosis is guarded (Guilford ), although long‐term remission can be achieved following surgical excision of the lesion (Watson et al . ). The transmural regional granulomatous inflammation of the ileum and proximal colon has similarity with human Crohn's disease (CD) (Baumgart & Sandborn , Freeman ).…”

“…, Watson et al . ). The potential role of infectious agents and the similarity to CD have not been thoroughly examined.…”