Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 3 complete abstracts (679 words), 9 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
A form of alveolitis or pneumonitis due to an acquired hypersensitivity to inhaled antigens associated with farm environment. Antigens in the farm dust are commonly from bacteria actinomycetes (saccharopolyspora and thermoactinomyces), fungi, and animal proteins in the soil, straw, crops, pelts, serum, and excreta.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Farmer Lung; Farmers Lung; Farmer's Lungs; Mushroom Worker's Lung; Mushroom Worker Lung; Mushroom Workers Lung; Mushroom Worker's Lungs.
Where it fits in the MeSH classification
- Broader topics
- Alveolitis, Extrinsic Allergic; Agricultural Workers' Diseases
Related concepts
- Saccharopolyspora
- Thermoactinomyces
Research landscape
PubMed indexes 1,039 records tagged with the MeSH heading “Farmer's Lung” (counts retrieved 2026-10-29). 8 of them (0.8%) were published from 2020 onward, and the busiest period so far is through 1999 with 945 records.
Reviews account for 67 records (6.4%) and meta-analyses for 0. Randomized controlled trials number 3 (0.3%) as a share of all records on the topic. Randomized trials make up only a small share of this literature, so much of what is known comes from laboratory, observational or descriptive work.
Show the data
| Period | Records |
|---|---|
| through 1999 | 945 |
| 2000-2009 | 53 |
| 2010-2019 | 33 |
| 2020 onward | 8 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 67 | 6.4% |
| Meta-analyses | 0 | 0.0% |
| Randomized controlled trials | 3 | 0.3% |
Method: PubMed query "Farmer's Lung"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-29.
Reading the evidence in immunology
Immune responses are studied in model organisms, in cells from donors and in patients, and the same pathway can behave differently across these settings. Mouse immune systems differ from human ones in important ways, and blood measurements may not reflect what happens in tissues. Clinical conclusions about immune-mediated disease or immunotherapy come mainly from controlled trials and long-term cohorts. Check the species and tissue studied, whether markers were linked to outcomes patients notice, and the follow-up time.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Daily exposure to dust alters innate immunity | 2012 | Research article Design not recorded in structured metadata | 31 | cc by PMID 22355383 · DOI · PMC3280315 |
| Emphysema in active farmer's lung disease | 2017 | Research article Design not recorded in structured metadata | 18 | cc by PMID 28614400 · DOI · PMC5470683 |
| Identification of Antigenic Proteins from Lichtheimia corymbifera for Farmer's Lung Disease Diagnosis | 2016 | Research article Design not recorded in structured metadata | 11 | cc by PMID 27490813 · DOI · PMC4973876 |
Daily exposure to dust alters innate immunity [1]
Abstract reading summary — source excerpts
- Opening excerpt
- Pig farmers are exposed to organic material in pig barns on a daily basis and have signs of an ongoing chronic airway inflammation and increased prevalence of chronic inflammatory airway diseases, predominantly chronic bronchitis.
- Closing excerpt
- In conclusion, farmers have signs of local and systemic inflammation associated with altered innate immunity characteristics.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (251 words)
Pig farmers are exposed to organic material in pig barns on a daily basis and have signs of an ongoing chronic airway inflammation and increased prevalence of chronic inflammatory airway diseases, predominantly chronic bronchitis. Interestingly, the inflammatory response to acute exposure to organic dust is attenuated in farmers. The aim of the study was to closer characterize innate immunity features in blood and airways in farmers and in naïve, non-exposed, controls. The expression of pattern recognition receptors (TLR2, TLR4 and CD14) whose ligands are abundant in pig barn dust and adhesion proteins (CD11b, CD62L and CD162L) on blood and sputum neutrophils in pig farmers and soluble TLR2 and CD14 (sTLR2 and sCD14) in blood and sputum were assessed in pig farmers and previously unexposed controls. The release of pro-inflammatory cytokines from blood cells stimulated with LPS ex vivo was measured in the absence and presence of anti-ST2. We also examined, in a separate study population, serum levels of soluble ST2 (sST2), before and after exposure in a pig barn and a bronchial LPS challenge. Farmers had signs of ongoing chronic inflammation with increased number of blood monocytes, and decreased expression of CD62L and CD162 on blood neutrophils. Farmers also had lower levels of sTLR2 and sCD14 in sputum and reduced expression of CD14 on sputum neutrophils than controls. Exposure to organic dust and LPS induced increase of serum sST2 in controls but not in farmers. In conclusion, farmers have signs of local and systemic inflammation associated with altered innate immunity characteristics.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 22355383 · DOI · PMC3280315
Emphysema in active farmer's lung disease [2]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundFarmer's lung (FL) is a common type of hypersensitivity pneumonitis.
- Closing excerpt
- ConclusionEmphysema is found in half of patients with active FL and may be influenced by exposure patterns.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (196 words)
BackgroundFarmer's lung (FL) is a common type of hypersensitivity pneumonitis. It is often considered that fibrosis is the most frequent finding in chronic FL. Nevertheless, three cohort studies have suggested that some patients with chronic FL may develop emphysema. We aimed to evaluate the current prevalence of emphysema in active FL, to describe the radiological and functional features of emphysema in active FL, and to identify risk factors associated with emphysema in this population.MethodsPatients aged over 18 years with active FL were prospectively recruited through the SOPHIA study (CPP Est; P-2009-521), between 2007 and 2015. Each patient had complete medical history screening, clinical examination, high resolution computed tomodensitometry, bronchoalveolar lavage, pulmonary function tests and serum precipitins.ResultsAmong 33 patients with active FL, the prevalence of emphysema in this series of incident active FL cases was higher (48.5%) than that of fibrosis (12%) and was not dependent on smoking habits. Most patients with emphysema did not have lung hyperinflation. The possible risk factors for emphysema in active FL were a longer duration of exposure to organic dusts, and at a higher level.ConclusionEmphysema is found in half of patients with active FL and may be influenced by exposure patterns.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 28614400 · DOI · PMC5470683
Identification of Antigenic Proteins from Lichtheimia corymbifera for Farmer's Lung Disease Diagnosis [3]
Abstract reading summary — source excerpts
- Opening excerpt
- The use of recombinant antigens has been shown to improve both the sensitivity and the standardization of the serological diagnosis of Farmer's lung disease (FLD).
- Closing excerpt
- corymbifera represents an additional step towards the development of a standardized ELISA kit for FLD diagnosis.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (232 words)
The use of recombinant antigens has been shown to improve both the sensitivity and the standardization of the serological diagnosis of Farmer's lung disease (FLD). The aim of this study was to complete the panel of recombinant antigens available for FLD serodiagnosis with antigens of Lichtheimia corymbifera, known to be involved in FLD. L. corymbifera proteins were thus separated by 2D electrophoresis and subjected to western blotting with sera from 7 patients with FLD and 9 healthy exposed controls (HEC). FLD-associated immunoreactive proteins were identified by mass spectrometry based on a protein database specifically created for this study and subsequently produced as recombinant antigens. The ability of recombinant antigens to discriminate patients with FLD from controls was assessed by ELISA performed with sera from FLD patients (n = 41) and controls (n = 43) recruited from five university hospital pneumology departments of France and Switzerland. Forty-one FLD-associated immunoreactive proteins from L. corymbifera were identified. Six of them were produced as recombinant antigens. With a sensitivity and specificity of 81.4 and 77.3% respectively, dihydrolipoyl dehydrogenase was the most effective antigen for discriminating FLD patients from HEC. ELISA performed with the putative proteasome subunit alpha type as an antigen was especially specific (88.6%) and could thus be used for FLD confirmation. The production of recombinant antigens from L. corymbifera represents an additional step towards the development of a standardized ELISA kit for FLD diagnosis.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 27490813 · DOI · PMC4973876
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article Organic dust toxic syndrome: an acute febrile reaction to organic dust exposure distinct from hypersensitivity pneumonitis [4]
- Research article Farmer's Lung Disease. A Review [5]
- Research article Farmer's lung disease [6]
- Research article Farmer's lung [7]
- Research article Lung disease in farmers [8]
- Research article Clinical aspects of farmer's lung: airway reactivity, treatment and prognosis [9]
References
- Sahlander K, Larsson K, Palmberg L. Daily exposure to dust alters innate immunity. . 2012. PMID 22355383 · DOI · PMC3280315
- Soumagne T, Chardon ML, Dournes G, Laurent L, Degano B, Laurent F, et al.. Emphysema in active farmer's lung disease. . 2017. PMID 28614400 · DOI · PMC5470683
- Rognon B, Barrera C, Monod M, Valot B, Roussel S, Quadroni M, et al.. Identification of Antigenic Proteins from Lichtheimia corymbifera for Farmer's Lung Disease Diagnosis. . 2016. PMID 27490813 · DOI · PMC4973876
- Von Essen S, Robbins RA, Thompson AB, Rennard SI. Organic dust toxic syndrome: an acute febrile reaction to organic dust exposure distinct from hypersensitivity pneumonitis. J Toxicol Clin Toxicol. 1990. PMID 2269997 · DOI
- Cano-Jiménez E, Acuña A, Botana MI, Hermida T, González MG, Leiro V, et al.. Farmer's Lung Disease. A Review. Arch Bronconeumol. 2016. PMID 26874898 · DOI
- Emanuel DA, Kryda MJ. Farmer's lung disease. Clin Rev Allergy. 1983. PMID 6367928
- Chmelik F, DoPico G, Reed CE, Dickie H. Farmer's lung. J Allergy Clin Immunol. 1974. PMID 4604472 · DOI
- Warren CP. Lung disease in farmers. Can Med Assoc J. 1977. PMID 321110 · PMC1879238
- Mönkäre S. Clinical aspects of farmer's lung: airway reactivity, treatment and prognosis. Eur J Respir Dis Suppl. 1984. PMID 6426996
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-29.
See how EvidenceLib is built. Spotted an error? Email support@evidencehelix.com.
Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.