Lawsonia Intracellularis Infections in Porcine Health

Lawsonia intracellularis is an obligate intracellular bacterium responsible for porcine proliferative enteropathy, commonly known as ileitis. This fastidious pathogen colonises enterocytes of the distal small intestine, inducing marked crypt hyperplasia and a spectrum of clinical signs ranging from subclinical growth retardation to severe diarrhoea and mucosal ulceration. The economic burden is substantial, driven by reduced weight gain, impaired feed conversion and increased mortality in weaner and finishing pigs worldwide. Pathogenesis involves intimate impairment of epithelial cell homeostasis, with infection triggering inflammatory cascades, epithelial restitution pathways and alterations in nutrient transport. Diagnostic strategies encompass histopathology, serological assays, real-time PCR and emerging cell‐based methods. Control measures have historically relied on in‐feed antibiotic growth promoters, though shifting regulations have spurred vaccine development and alternative interventions such as probiotics and microbiome modulation. Recent advances in molecular biology have illuminated aspects of host–pathogen interaction, immune‐mediated protection and the genomic uniformity of global strains. Understanding these interconnections is vital for designing integrated control programmes that safeguard animal welfare, enhance production efficiency and mitigate the global spread of this economically significant pathogen.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Lawsonia Intracellularis Infections in Porcine Health publication trend

The graph below shows the total number of articles in lawsonia intracellularis infections in porcine health across all publications each year (not limited to Nature Index journals).

Technical terms

Obligate intracellular bacterium: A microorganism that can only replicate within the cells of a host organism.

Proliferative enteropathy (ileitis): A disease of the small intestine characterised by the thickening of the intestinal wall due to excessive proliferation of epithelial cells.

Real-time PCR: A molecular technique that amplifies and quantifies specific DNA sequences in real time, used for sensitive pathogen detection.

Flow cytometry antibody test (FCAT): A serological assay that employs flow cytometry to detect antibodies bound to whole bacterial cells, yielding high-precision immunoprofiling.

Optical density spectrophotometry: A method that measures the turbidity of a bacterial suspension at specific wavelengths to estimate cell concentration indirectly.

References

1. Development and validation of a flow cytometry antibody test for Lawsonia intracellularis. Frontiers in Immunology (2023).
2. New Method for Lawsonia intracelullaris Quantification Based on Optical Density by Spectrophotometry. Microorganisms (2025).
3. Alleviative Effect of Probiotic Ferment on Lawsonia intracellularis Infection in Piglets. Biology (2023).
4. Lawsonia intracellularis: Revisiting the Disease Ecology and Control of This Fastidious Pathogen in Pigs. Frontiers in Veterinary Science (2018).
5. A Cell Proliferation and Inflammatory Signature Is Induced by Lawsonia intracellularis Infection in Swine. mBio (2019).
6. Metagenomic sequencing of clinical samples reveals a single widespread clone of Lawsonia intracellularis responsible for porcine proliferative enteropathy. Microbial Genomics (2020).