Molecular test for Lundehund syndrome (LHS), a hereditary chronic enteropathy of the Norwegian Lundehund that causes chronic diarrhoea, weight loss and protein-losing enteropathy with hypoalbuminaemia. It affects the gastrointestinal system and compromises nutritional status and survival. The test reports the clear/carrier/affected status for the corresponding variant.

Applicable breed: Norwegian Lundehund. Clinical prevalence is high in the breed (published data place it as a major health problem); exact figures by country are limited and should be verified in the specific literature.

- Chronic diarrhoea, often with steatorrhoea\n- Weight loss and poor body condition\n- Hypoalbuminaemia and oedema due to protein-losing enteropathy\n- Intestinal lymphangiectasia on biopsy\n- Intermittent course with flare-ups

Lundehund syndrome was described as a breed-based chronic enteropathy with intestinal lymphangiectasia and hypoalbuminaemia in the Norwegian Lundehund. The molecular characterisation (GWAS on CFA34 and analysis of regions of homozygosity) identified a missense mutation in P3H2 (LEPREL1) with recessive major-gene inheritance. The breed has undergone population bottlenecks that are associated with the high prevalence of the disease.

- Genotype breeding animals before mating\n- With confirmed autosomal recessive inheritance, do not mate two carriers and do not use affected homozygous animals in breeding\n- A carrier can be mated to a clear animal; test the offspring intended for breeding\n- Assess the gastrointestinal phenotype of the breeding animals\n- Given the population bottleneck, prioritise genetic diversity and avoid close inbred matings\n- After a confirmed clinical case, do not repeat the parental mating and communicate the status to the buyer

Differential diagnosis with idiopathic inflammatory enteropathy (IBD), intestinal lymphoma, exocrine pancreatic insufficiency and malabsorption due to parasitosis. Confirmation by endoscopy/intestinal biopsy (lymphangiectasia) and biochemistry (hypoalbuminaemia, hypocholesterolaemia). Dietary management (digestible, low-fat), fat-soluble vitamin supplementation and immunomodulatory treatment in selected cases.

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