Unexplained bronchopulmonary disease with inflammatory bowel disease

Unraveling the gut-Lung axis: Exploring complex mechanisms in disease interplay

The link between gut and lung starts as early as during organogenesis. Even though they are anatomically distinct, essential bidirectional crosstalk via complex mechanisms supports GLA. Emerging studies have demonstrated the association of gut and lung diseases via multifaceted mechanisms. Advancements in omics and metagenomics technologies revealed a potential link between gut and lung microbiota, adding further complexity to GLA. Despite substantial studies on GLA in various disease models, mechanisms beyond microbial dysbiosis regulating the interplay between gut and lung tissues during disease conditions are not thoroughly reviewed. This review outlines disease specific GLA mechanisms, emphasizing research gaps with a focus on gut-to-lung direction based on current GLA literature. Moreover, the review discusses potential gut microbiota and their products like metabolites, immune modulators, and non-bacterial contributions as a basis for developing treatment strategies for lung diseases. Advanced experimental methods, modern diagnostic tools, and technological advancements are also highlighted as crucial areas for improvement in developing novel therapeutic approaches for GLA-related diseases. In conclusion, this review underscores the importance of exploring additional mechanisms within the GLA to gain a deeper understanding that could aid in preventing and treating a wide spectrum of lung diseases.

Case report: Confusing lung signs - is the source of the disease in the lungs or intestines?

At the time of the spread of the COVID-19 epidemic, blurred lung signs suggested by imaging examination are particularly common. Novel coronavirus infection is mainly caused by respiratory symptoms. In the early stage of imaging examination, multiple small patchy shadows or ground glass shadows and invasive shadows of both lungs are dominant. While the pulmonary involvement in Crohn's disease (CD) is rare and not widely reported. For CD patients, the pulmonary manifestations do not belong to its routine symptoms. The lung involvement of CD patients is difficult to attract clinicians' attention. If CD patients have vague lung manifestations but have no response to routine treatment, they should consider the respiratory diseases related to CD. We describe a rare case of granulomatous inflammation associated with Crohn's disease. The patient do not respond to conventional treatment. The final treatment plan was CD immunomodulatory therapy (oral corticosteroids and azathioprine). After treatment, a review of the lung CT showed focal fibrosis and significant improvement in the lung lesions. It suggests that CD related respiratory diseases should be considered when CD patients have abnormal lung manifestations that do not respond to conventional treatment.

Pulmonary manifestation of inflammatory bowel disease: Two case reports

Pulmonary involvement associated with inflammatory bowel disease (IBD) are a rare extraintestinal manifestation (EIM) of inflammatory bowel disease (IBD), we herein presented two cases. Case 1: 53-year-old man with Crohn's disease treated with mesalazine and azathioprine. Pulmonary nodular shadows were incidentally detected on chest imaging, and revealed granulomas through transbronchial lung biopsy. Case 2: 68-year-old man with ulcerative colitis treated with mesalazine. He presented with fever and respiratory symptoms, and chest imaging showed multiple nodular infiltrates. He was diagnosed with organizing pneumonia by lung biopsy. Both cases were diagnosed to have pulmonary involvement associated with inflammatory bowel disease (IBD) according to multidisciplinary examination including positron emission tomography-computed tomography (FDG-PET) and pathological test. Pulmonary manifestations with IBD may not always require discontinuation of drugs or additional use of steroids or immunosuppressants.

Experimental allergic airway inflammation impacts gut homeostasis in mice

Background

/Aims: Epidemiological data show that there is an important relationship between respiratory and intestinal diseases. To improve our understanding on the interconnectedness between the lung and intestinal mucosa and the overlap between respiratory and intestinal diseases, our aim was to investigate the influence of ovalbumin (OVA)-induced allergic airway inflammation on gut homeostasis.

Methods

A/J mice were sensitized and challenged with OVA. The animals were euthanized 24 h after the last challenge, lung inflammation was determined by evaluating cells in Bronchoalveolar lavage fluid, serum anti-OVA IgG titers and colon morphology, inflammation and integrity of the intestinal mucosa were investigated. IL-4 and IL-13 levels and myeloperoxidase activity were determined in the colon samples. The expression of genes involved in inflammation and mucin production at the gut mucosa was also evaluated.

Results

OVA challenge resulted not only in lung inflammation but also in macroscopic alterations in the gut such as colon shortening, increased myeloperoxidase activity and loss of integrity in the colonic mucosal. Neutral mucin intensity was lower in the OVA group, which was followed by down-regulation of transcription of ATOH1 and up-regulation of TJP1 and MUC2. In addition, the OVA group had higher levels of IL-13 and IL-4 in the colon. Ova-specific IgG1 and OVA-specific IgG2a titers were higher in the serum of the OVA group than in controls.

Conclusions

Our data using the OVA experimental model suggested that challenges in the respiratory system may result not only in allergic airway inflammation but also in the loss of gut homeostasis.

A 52-Year-Old Woman With a History of Ulcerative Colitis and New Onset Severe Dyspnea

CASE PRESENTATION

A 52-year-old woman was referred to the pulmonary office for evaluation of worsening dyspnea in August 2022. She had been diagnosed with asthma 22 years ago after she experienced chronic cough, sputum production, occasional wheezing, and mild exertional shortness of breath. Over the years, she was treated with different inhalers and was currently on triple inhaler therapy. A pulmonary function test in 2020 was normal. She had a history of ulcerative colitis and underwent a total colectomy in 1998. In the early 2000s, the patient also experienced episcleritis. Her other medical conditions included hyperlipidemia, gout, and gastroesophageal reflux disease.

Prevalence of and Factors Associated with Respiratory Symptoms Among Patients with Inflammatory Bowel Disease: A Prospective Study

BACKGROUND

No large, prospective study has investigated respiratory symptoms in patients with inflammatory bowel diseases. We aimed to describe the prevalence of and factors associated with respiratory symptoms in patients with inflammatory bowel disease.

METHODS

In an observational, prospective, cross-sectional study, we evaluated the frequency of respiratory symptoms using a validated self-reporting questionnaire from February 2019 to February 2021 during routine follow-up outpatient visits of patients with inflammatory bowel disease followed in the Gastroenterology Department of the Nancy University Hospital. In case of a positive questionnaire, patients were systematically offered a consultation with a pulmonologist in order to investigate a potential underlying respiratory disease.

RESULTS

There were 325 patients included, and 180 patients had a positive questionnaire (144 with Crohn's disease). Of the included patients, 165 (50.8%) presented with respiratory symptoms, with dyspnea being the most frequent symptom (102 patients). There were 102 patients (56.7%) who benefited from a consultation in the pulmonology department: 43 (42.2%) were diagnosed with a respiratory disease, mainly asthma (n = 13) or chronic obstructive pulmonary disease (n = 10). Fourteen patients (13.7%) had obstructive sleep apnea. A body mass index increase, being a smoker or ex-smoker, and having articular extra-intestinal manifestations were independently associated with a higher prevalence of respiratory symptoms.

CONCLUSIONS

Half of patients with inflammatory bowel disease reported respiratory symptoms in our study. Patients with inflammatory bowel disease should be systematically screened, as pulmonary disease is frequently present in this population, with specific attention being given to smokers or ex-smokers and patients with extra-articular intestinal manifestations.

The central role of the gut in intensive care

Critically ill patients undergo early impairment of their gut microbiota (GM) due to routine antibiotic therapies and other environmental factors leading to intestinal dysbiosis. The GM establishes connections with the rest of the human body along several axes representing critical inter-organ crosstalks that, once disrupted, play a major role in the pathophysiology of numerous diseases and their complications. Key players in this communication are GM metabolites such as short-chain fatty acids and bile acids, neurotransmitters, hormones, interleukins, and toxins. Intensivists juggle at the crossroad of multiple connections between the intestine and the rest of the body. Harnessing the GM in ICU could improve the management of several challenges, such as infections, traumatic brain injury, heart failure, kidney injury, and liver dysfunction. The study of molecular pathways affected by the GM in different clinical conditions is still at an early stage, and evidence in critically ill patients is lacking. This review aims to describe dysbiosis in critical illness and provide intensivists with a perspective on the potential as adjuvant strategies (e.g., nutrition, probiotics, prebiotics and synbiotics supplementation, adsorbent charcoal, beta-lactamase, and fecal microbiota transplantation) to modulate the GM in ICU patients and attempt to restore eubiosis.

Incidence, Characteristics, Clinical Course, and Risk Factors of Ulcerative Colitis-related Lung Diseases

BACKGROUND

Ulcerative colitis (UC) is a chronic GI inflammatory disorder involving various extraintestinal organs, including the lungs. Although UC-related lung diseases (UC-LDs) have been widely recognized, much remains unclear.

RESEARCH QUESTION

What are the incidence, characteristics, clinical course, and risk factors of UC-LD?

STUDY DESIGN AND METHODS

This study retrospectively identified and classified UC-LDs by reviewing the medical records of consecutive patients with UC. The incidence, characteristics, and clinical course of each UC-LD type were investigated, and the clinical characteristics of patients with and without each UC-LD type were compared.

RESULTS

Among 563 patients with UC, 28 (5.0%) developed UC-LD during a mean follow-up period of 77 months. A majority of them displayed airway disease (AD) (n = 13 [2.3%]) or organizing pneumonia (OP) (n = 10 [1.8%]); there were six cases of interstitial pneumonias other than OP (IP) (0.8%) and one of pleuritis (0.2%). All 13 patients with AD responded favorably to inhaled or systemic corticosteroids, although five experienced frequent exacerbations. Older age and a history of colectomy were identified as the risk factors for developing AD. Nine of the 10 cases of OP were possibly due to drug-induced pathogenesis. Only one case showed recurrence, and all cases of OP exhibited a favorable clinical course with discontinuation of the suspicious drug and/or initiation of corticosteroid. The clinical course of IP depended on the existence of fibrosis, and IP with fibrosis was associated with gradual deterioration. Older age was associated with the development of IP.

INTERPRETATION

A nonnegligible number of patients with UC may develop UC-LD. AD, OP, and IP without fibrosis show good prognosis following steroid therapy along with the specific management for each UC-LD type, whereas IP with fibrosis shows gradual deterioration with poor prognosis. Our results provide cues to establish better management of UC-LDs.

Pulmonary Crohn's Disease or Crohn's Disease with Lung Sarcoidosis? A Case Report and Literature Review

BACKGROUND

Crohn's disease and ulcerative hemorrhagic colitis are forms of granulomatous inflammatory intestinal disease, which usually affects the gastrointestinal tract. There are also reported rare localizations at the skin, kidney, joints, liver and eye level. Pulmonary involvement is relatively rare, and it is most commonly reported in suppuration with bronchiectasis. On the other hand, sarcoidosis is, in principle, a thoracic localization of a granulomatosis disease, although bowel, skin and intestinal disorders are described. There is not a clear line to separate Crohn's disease from sarcoidosis with, possibly because they are, in fact, considered to have the same inflammatory granulomatosis disease pathology. The diagnoses of the two entities, sarcoidosis and Crohn's disease, are based on non-pathognomonic, inclusive clinical and paraclinical criteria, without elements of the mutual exclusion of typical locations.

CASE REPORT

We present a very rare case of a young male, already diagnosed with small-bowel Crohn's disease. Granulomatous lung disease with major hemoptysis requires emergency surgery. An intraoperative assessment revealed a necrotic hemorrhagic lesion located in the left lower lobe and a lobectomy was performed. The final pathological report showed the presence of non-caseous granulomatous inflammation, with the identification of specific multinucleated giant cells.

CONCLUSIONS

The identical diagnostic principles of Crohn's disease and sarcoidosis, Crohn's disease as a predecessor to pulmonary lesions, the clinical picture and the necrotico-hemorrhagic appearance of the unilateral pulmonary lesion, which are similar to aggressive necrotico-hemorrhagic or perforating intestinal forms, are arguments in favor of the diagnosis of pulmonary Crohn's disease and not pulmonary sarcoidosis. At the same time, in general, the two diseases have overlapping elements, suggesting they are, in fact, not the same disease with different facets.

Interstitial Lung Disease as an Extraintestinal Manifestation of Crohn's Disease in the Time of COVID-19: A Rare Case Report and Review of the Literature

Introduction

Recently, the extraintestinal manifestations of Crohn's disease (CD) have attracted more and more attention, among which interstitial lung disease (ILD) is a rare extraintestinal manifestation. Clinical presentation is polymorphic and pathogenesis remains unclear. The purpose of this article is to elaborate on these rare extraintestinal manifestations of CD, and the importance of short-term chest computed tomography (CT) for differential diagnosis is emphasized.

Case Presentation

A 27-year-old male patient, who is a student, presented with chief complaints of "loose stools for 4 months, intermittent low-grade fever for 1 month". The next day, he developed a high fever with a body temperature of 39.8°C. A chest CT scan revealed multiple patellar ground glass shadows which suggested ILD. In the time of Corona virus disease (COVID-19), novel coronavirus pneumonia was first suspected according to the patient's history and symptoms, but laboratory examinations did not confirm. Colonoscopy showed multiple ulcers between the sigmoid colon to the terminal ileum, and pathology found epithelioid granuloma in submucosa. Moreover, a total gastrointestinal CT angiography showed that segmental leaping thickening of the bowel. Based on the above results, we ultimately made a diagnosis of CD. After using systemic steroid therapy, his fever was quickly relieved, and a follow-up chest CT showed that multiple patellar ground glass shadows were almost completely absorbed. Then, infliximab was used, and a repeat colonoscopy showed that intestinal ulcers were significantly improved.

Conclusion

ILD is a rare extraintestinal manifestation of CD and reveals the excellent response to systemic steroid therapy. Manifestations of pulmonary disease associated with IBD are polymorphic; therefore; clinicians should be more vigilant regarding IBD-related ILD, especially when infectious causes have been excluded in the time of COVID-19. For those with ILD related to IBD, a short-term follow-up CT would be crucial.

Aeroallergen-related Diseases Predate the Diagnosis of Inflammatory Bowel Disease

OBJECTIVE

This study aimed to determine whether having a diagnosis of asthma or allergic rhinitis (AR) increased the risk of being diagnosed with inflammatory bowel disease (IBD) and whether there was increased incidence of these diseases after a diagnosis of IBD.

DESIGN

This is a retrospective, historical cohort-based study. We used the administrative data of Manitoba Health and the population-based University of Manitoba IBD Epidemiology Database. We used numbers of prescriptions for drugs used to treat asthma and to treat AR to identify diagnoses of asthma and AR, respectively.We calculated relative risks (RRs) to assess incidence of IBD compared with matched controls after diagnoses of asthma and AR and hazard ratios to determine the incidence of asthma and AR after IBD diagnosis.

RESULTS

Compared with controls, a diagnosis of asthma or AR preceding a diagnosis of IBD was increased in cases (RR, 1.62; 95% confidence interval [CI], 1.50-1.75; and RR, 2.10; 95% CI, 1.97-2.24) with a similar outcome by subtype of IBD (Crohn's disease vs ulcerative colitis) and by sex. On sensitivity analysis, diagnoses of asthma or AR were comparable when considering at least 5, 10, 15 or 20 drug prescriptions. Persons with IBD were more likely to develop asthma or AR than controls after being diagnosed with IBD (hazard ratio for asthma, 1.31, 95% CI, 1.18-1.45; and hazard ratio for AR, 2.62, 95% CI, 2.45-2.80).

CONCLUSIONS

The association between asthma, AR, and IBD suggest the possibility that whatever triggers the onset of these atopic diseases may trigger the onset of IBD as well, and aeroallergens are plausible culprits.

Pathophysiological Concepts and Management of Pulmonary Manifestation of Pediatric Inflammatory Bowel Disease

Pulmonary manifestation (PM) of inflammatory bowel disease (IBD) in children is a rare condition. The exact pathogenesis is still unclear, but several explanatory concepts were postulated and several case reports in children were published. We performed a systematic Medline search between April 1976 and April 2022. Different pathophysiological concepts were identified, including the shared embryological origin, “miss-homing” of intestinal based neutrophils and T lymphocytes, inflammatory triggering via certain molecules (tripeptide proline-glycine-proline, interleukin 25), genetic factors and alterations in the microbiome. Most pediatric IBD patients with PM are asymptomatic, but can show alterations in pulmonary function tests and breathing tests. In children, the pulmonary parenchyma is more affected than the airways, leading histologically mainly to organizing pneumonia. Medication-associated lung injury has to be considered in pulmonary symptomatic pediatric IBD patients treated with certain agents (i.e., mesalamine, sulfasalazine or infliximab). Furthermore, the risk of pulmonary embolism is generally increased in pediatric IBD patients. The initial treatment of PM is based on corticosteroids, either inhaled for the larger airways or systemic for smaller airways and parenchymal disease. In summary, this review article summarizes the current knowledge about PM in pediatric IBD patients, focusing on pathophysiological and clinical aspects.

The Immune Change of the Lung and Bowel in an Ulcerative Colitis Rat Model and the Protective Effect of Sodium Houttuyfonate Combined With Matrine

Objective

To explore the immune change of lung injury of Ulcerative colitis (UC) by observing the changes of inherent immunity and adaptive immunity of the lung and bowel in UC rat models after the treatment of Sodium Houttuyfonate combined with Matrine.

Method

UC rat models were established with the mucous membrane of colon allergize combined with TNBS-alcohol enteroclysis for 1 week and 5 weeks. 1-week experimental rats were divided into normal group and model group, 5/each group. 5-weeks experimental rats were divided into normal group, model group, Sodium Houttuyfonate (2.9mg/ml) combined with Matrine (1.47mg/ml), and positive control sulfasalazine (10mg/ml), 5/each group. All rats were administered by gavage for 5 weeks. The histopathological and fibrotic changes in the lung and bowel were observed, and the expressions of Tumor Necrosis Factor (TNF)- α, interleukin (IL)-8 in the lung, bowel, and serum were detected by radio-immunity and immunohistochemistry, and the mRNA expressions of Toll-like receptor (TLR)-4, nuclear factor kappa (NF-κB), Macrophage migration inhibitory factor (MIF), Mucosal addressing cell adhesion molecule-1 (MadCAM1) and Pulmonary surfactant protein-A (SP-A) in the lung and bowel were detected by Real time-PCR.

Result

Compared with the normal group, the model rats had significant histopathological and fibrotic changes both in the lung and bowel, and all treatment groups were improved. After treatment, TLR4, IL-8, MIF, and TNF-α in the lung decreased (P<0.05); NF-KB, IL-8, and MIF in the bowel increased (P<0.05); MadCAM1 both in lung and bowel decreased (P<0.05); SP-A decreased in bowel and increased in the lung (P<0.05).

Conclusion

The cause of lung injury in this model was found to be related to inherent immunity and adaptive immunity, while the cause of bowel injury in this model was found to be mainly related to adaptive immunity. Sodium Houttuyfonate combined with Matrine could improve bowel and lung injury.

Gegen Qinlian Decoction Alleviates Experimental Colitis and Concurrent Lung Inflammation by Inhibiting the Recruitment of Inflammatory Myeloid Cells and Restoring Microbial Balance

Objective

Ulcerative colitis (UC) as one of the intractable diseases in gastroenterology seriously threatens human health. Respiratory pathology is a representative extraintestinal manifestation of UC affecting the quality of life of patients. Gegen Qinlian Decoction (GQD) is a classical traditional Chinese medicine prescription for UC or acute lung injury. This study was aimed to reveal the therapeutic effect of GQD on UC and its pulmonary complications and uncover its molecular mechanism mediated by myeloid cells and microbiota.

Methods

Mice with DSS-induced colitis were orally administrated with GQD. Overall vital signs were assessed by body weight loss and disease activity index (DAI). Pulmonary general signs were evaluated by pulmonary pathology and lung function. The mechanism of GQD relieving UC was characterized by detecting myeloid cells (neutrophils, macrophages, inflammatory monocytes, and resident monocytes) in colonic and lung tissues, related inflammatory cytokines, as well as the microbiota in bronchoalveolar lavage fluid (BALF) and feces.

Results

GQD significantly reduced weight loss, DAI scores, and lung injury but improved the lung function of colitis mice. The DSS-induced colonic and concurrent pulmonary inflammation were also alleviated by GQD, as indicated by the down-regulated expressions of inflammatory cytokines (TNF-α, IL-1β, IL-6, CCR2, and CCL2) and the suppressed recruitment of neutrophils and inflammatory monocytes. Meanwhile, GQD greatly improved intestinal microbiota imbalance by enriching Ruminococcaceae UCG-013 while decreasing Parabacteroides, [Eubacterium]_fissicatena_group, and Akkermansia in the feces of colitis mice. Expectantly, GQD also restored lung microbiota imbalance by clearing excessive Coprococcus 2 and Ochrobactrum in the BALF of colitis mice. Finally, significant correlations appeared between GQD-mediated specific bacteria and inflammatory cytokines or immune cells.

Conclusion

GQD could alleviate UC by decreasing excessive inflammatory myeloid cells and cytokines, and reshaping the microbiota between the colon and lung, which contributes to clarifying the mechanism by which GQD ameliorates colitis-associated pulmonary inflammation.

Role of Gut Microbiome in COVID-19: An Insight Into Pathogenesis and Therapeutic Potential

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), resulted in an unprecedented global crisis. Although primarily a respiratory illness, dysregulated immune responses may lead to multi-organ dysfunction. Prior data showed that the resident microbial communities of gastrointestinal and respiratory tracts act as modulators of local and systemic inflammatory activity (the gut-lung axis). Evolving evidence now signals an alteration in the gut microbiome, brought upon either by cytokines from the infected respiratory tract or from direct infection of the gut, or both. Dysbiosis leads to a "leaky gut". The intestinal permeability then allows access to bacterial products and toxins into the circulatory system and further exacerbates the systemic inflammatory response. In this review, we discuss the available data related to the role of the gut microbiome in the development and progression of COVID-19. We provide mechanistic insights into early data with a focus on immunological crosstalk and the microbiome's potential as a biomarker and therapeutic target.

Microbiome in Critical illness: An Unconventional and Unknown Ally

BACKGROUND

The digestive tract represents an interface between the external environment and the body where the interaction of a complex polymicrobial ecology has an important influence on health and disease. The physiological mechanisms that are altered during the hospitalization and in the intensive care unit (ICU) contribute to the pathobiota's growth. Intestinal dysbiosis occurs within hours of being admitted to ICU. This may be due to different factors, such as alterations of normal intestinal transit, administration of variuos medications or alterations in the intestinal wall which causes a cascade of events that will lead to the increase of nitrates and decrease of oxygen concentration, liberation of free radicals.

OBJECTIVE

This work aims to report the latest updates on the microbiota's contribution to developing sepsis in patients in the ICU department. In this short review were reviewed the latest scientific findings on the mechanisms of intestinal immune defenses performed both locally and systemically. In addition, we considered it necessary to review the literature to report the current best treatment strategies to prevent the infection spread which can bring systemic infections in patients admitted to ICU.

MATERIAL AND METHODS

This review has been written to answer at three main questions: what are the main intestinal flora's defense mechanisms that help us to prevent the risk of developing systemic diseases on a day-to-day basis? What are the main dysbiosis' systemic abnormalities? What are the modern strategies that are used in the ICU patients to prevent the infection spread? Using the combination of following keywords: microbiota and ICU, ICU and gut, microbiota and critical illness, microbiota and critical care, microbiota and sepsis, microbiota and infection, gastrointestinal immunity,in the Cochrane Controlled Trials Register, the Cochrane Library, medline and pubmed, google scholar, ovid/wiley. Finally, we reviewed and selected 72 articles. We also consulted the site ClinicalTrials.com to find out studies that are recently conducted or ongoing.

RESULTS

The critical illness can alter intestinal bacterial flora leading to homeostasis disequilibrium. Despite numerous mechanisms, such as epithelial cells with calciform cells that together build a mechanical barrier for pathogenic bacteria, the presence of mucous associated lymphoid tissue (MALT) which stimulates an immune response through the production of interferon-gamma (IFN-y) and THN-a or by stimulating lymphocytes T helper-2 produces anti-inflammatory cytokines. But these defenses can be altered following a hospitalization in ICU and lead to serious complications such as acute respiratory distress syndrome (ARDS), health care associated pneumonia (HAP) and ventilator associated pneumonia (VAP), Systemic infection and multiple organ failure (MOF), but also in the development of coronary artery disease (CAD). In addition, the microbiota has a significant impact on the development of intestinal complications and the severity of the SARS-COVID-19 patients.

CONCLUSION

The microbiota is recognized as one of the important factors that can worsen the clinical conditions of patients who are already very frailty in intensive care unit. At the same time, the microbiota also plays a crucial role in the prevention of ICU associated complications. By using the resources, we have available, such as probiotics, symbiotics or fecal microbiota transplantation (FMT), we can preserve the integrity of the microbiota and the GUT, which will later help maintain homeostasis in ICU patients.

Coronavirus disease-19 and the gut-lung axis

Gastrointestinal and respiratory tract diseases often occur together. There are many overlapping pathologies, leading to the concept of the ‘gut–lung axis’ in which stimulation on one side triggers a response on the other side. This axis appears to be implicated in infections involving severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which has triggered the global coronavirus disease 2019 (COVID-19) pandemic, in which respiratory symptoms of fever, cough and dyspnoea often occur together with gastrointestinal symptoms such as nausea, vomiting, abdominal pain and diarrhoea. Besides the gut–lung axis, it should be noted that the gut participates in numerous axes which may affect lung function, and consequently the severity of COVID-19, through several pathways. This article focuses on the latest evidence and the mechanisms that drive the operation of the gut–lung axis, and discusses the interaction between the gut–lung axis and its possible involvement in COVID-19 from the perspective of microbiota, microbiota metabolites, microbial dysbiosis, common mucosal immunity and angiotensin-converting enzyme II, raising hypotheses and providing methods to guide future research on this new disease and its treatments.

New Insights Into the Physiopathology of COVID-19: SARS-CoV-2-Associated Gastrointestinal Illness

Although SARS-CoV-2 is considered a lung-tropic virus that infects the respiratory tract through binding to the ACE2 cell-surface molecules present on alveolar lungs epithelial cells, gastrointestinal symptoms have been frequently reported in COVID-19 patients. What can be considered an apparent paradox is that these symptoms (e.g., diarrhea), sometimes precede the development of respiratory tract illness as if the breathing apparatus was not its first target during viral dissemination. Recently, evidence was reported that the gut is an active site of replication for SARS-CoV-2. This replication mainly occurs in mature enterocytes expressing the ACE2 viral receptor and TMPRSS4 protease. In this review we question how SARS-CoV-2 can cause intestinal disturbances, whether there are pneumocyte-tropic, enterocyte-tropic and/or dual tropic strains of SARS-CoV-2. We examine two major models: first, that of a virus directly causing damage locally (e.g., by inducing apoptosis of infected enterocytes); secondly, that of indirect effect of the virus (e.g., by inducing changes in the composition of the gut microbiota followed by the induction of an inflammatory process), and suggest that both situations probably occur simultaneously in COVID-19 patients. We eventually discuss the consequences of the virus replication in brush border of intestine on long-distance damages affecting other tissues/organs, particularly lungs.

Hafnia alvei pneumonia: a rare cause of infection in the multimorbid or immunocompromised

Hafnia alvei is a rare, poorly understood commensal bacterium which has, on occasion, been shown to infect humans. We present two cases. The first patient presented with a 1-week history of dyspnoea, pleurisy and a productive cough, and the second with a prodrome of fatigue and night sweats. The former had a history of severe chronic obstructive pulmonary disease and the latter had a history of Crohn's disease. Both patients had underlying comorbidities and immunosuppression, but differed in presentation, radiological findings and recovery. This case series aims to remind readers of the broad differential of pathogens that can lead to disease in the immunocompromised and that one should not dismiss atypical cultured bacteria as commensal too hastily.

Pulmonary Manifestations of Inflammatory Bowel Disease in Children

The recognition of pulmonary manifestations of inflammatory bowel disease (IBD) is important as these diseases can be confused with infectious etiologies (e.g., tuberculosis or fungal infection) and, as a result, may unnecessarily delay institution of appropriate therapy (e.g., infliximab). Furthermore, they are a source of morbidity that may be overlooked and, like other IBD-related pathologies, are often responsive to treatment with corticosteroids, immunomodulators, or biologic therapies. The purpose of this paper is to describe the cases of six children at a single institution with differing presentations, treatments, and responses to treatment of their IBD-related lung disease to improve recognition of this uncommon process.

Assessment of Occult Pulmonary Involvement in Ulcerative Colitis

Introduction

Nearly 50% of patients with inflammatory bowel disease (IBD) experience at least one extraintestinal manifestation. Bronchopulmonary involvement is rare in IBD. Pulmonary function test (PFT) abnormality in cases of ulcerative colitis (UC) has been reported to be 17-55%. Occult pulmonary disease may be diagnosed using variables of the PFT. Hence, we aim to evaluate the frequency and type of pulmonary dysfunction in patients with UC in remission.

Methods

Eighty-three patients of UC in remission and 48 controls underwent the PFT including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), Tiffeneau value (FEV1/FVC), and midexpiratory flow (MEF 25-75%) rate with a spirometer. The patients were divided based on the age of onset of UC into A1 (<16 years), A2 (16-40 years), and A3 (>40 years) and based on the extent of disease into E1 (proctitis), E2 (left-sided colitis), and E3 (extensive colitis).

Results

Patients with UC had significantly abnormal PFT compared with controls (51 [61.5%] vss. 8 [16.67%]; p = 0.000). Patients with UC commonly had a restrictive pattern (33 [64.47%]) of PFT followed by small airway disease (11 [21.56%]) and obstructive pattern (7 [13.72%]). Pulmonary involvement in cases of UC was more in E3 followed by E2 and E1. Pulmonary involvement was more in the late age of onset of disease. BMI was positively and significantly correlated with FEV1 and FVC. Hemoglobin had a positive and significant correlation with FEV1 while a negative correlation with FEV1/FVC and MEF 25-75%. All predictors except for age were found to contribute in higher risk (OR > 1) for PFT abnormality.

Conclusion

Patients with UC have chronic pulmonary inflammation leading to different patterns of lung involvement in the form of restrictive, obstructive airway, and small airway disease. Patients with UC commonly have a restrictive pattern of pulmonary involvement. Impairment of the PFT is related to the disease extent and the age of onset of disease. Assessment of the PFT using a spirometer is a noninvasive, simple, cost-effective, and reliable method for early detection of occult pulmonary involvement in patients of UC.

The impact of COVID-19 on intestinal flora: A protocol for systematic review and meta analysis

BACKGROUND

Coronavirus disease (COVID-19) sparked global concern for its outbreak and pandemic. It caused severe respiratory tract infections and a significant proportion of patients with gastrointestinal symptoms. Several studies have investigated the intestinal flora of COVID-19. However, so far there has been no evidence demonstrating the evidence on the association of COVID-19 with intestinal flora through meta-analysis. A systematic and comprehensive understanding of their relationship is essential to provide public health prevention or treatment strategy.

METHODS AND ANALYSIS

This systematic review and meta-analysis will be reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Observational studies (cohort studies, case-control, and cross-sectional studies) and clinical trials will be eligible. Studies eligible for inclusion must contain participants with COVID-19. Systematic searches will be conducted in PubMed, EMBASE, Cochrane Library, Ovid, EBSCO, World Health Organization COVID-19 database, China National Knowledge Internet, WanFang Data, Chinese Scientific and Technological Journal Database, and Chinese Biomedical Databases. A pre-designed search strategy of medical subject headings and free text terms for COVID-19 and intestinal flora will be used. Two reviewers will independently screen the titles and abstracts, followed by full-text screening. Discrepancies will be resolved by consensus with a third reviewer. The reviewers will then extract data from each eligible article based on PECOS (Population, Exposure, Comparator, Outcomes, and Study design). The risk of bias and quality of included studies will be assessed using an appropriate tool. A random-effects meta-analysis will be considered where there are sufficiently homogeneous studies; otherwise, a narrative synthesis will be conducted. Heterogeneity among studies will be assessed using I statistics. If substantial heterogeneity detected, subgroup analyses and meta-regression will be conducted to look for the potential causes.

ETHICS AND DISSEMINATION

Ethical approval is not required as we will use data from published articles. Findings will be published in a peer-reviewed journal.PROSPERO registration number: CRD42020191640.

Necrobiotic Pulmonary Nodules in Ulcerative Colitis: Not Just a "Crohnic" Phenomenon

Necrobiotic pulmonary nodules are an exceptionally rare extraintestinal manifestation of inflammatory bowel disease. Recognition is imperative because it may mimic other autoimmune pathologies such as granulomatosis with polyangiitis or sarcoidosis. We describe a 19-year-old man with a known history of ulcerative colitis who was found to possess bilateral pulmonary nodules on computed tomography imaging. Investigations that included an extensive autoimmune and infectious workup were inconclusive. Biopsy of the nodules revealed fibrinous exudate and palisading histiocytes that confirmed the diagnosis. He was started on prednisone therapy. A follow-up computed tomography a month later revealed near complete resolution.

The role of the microbiome and the NLRP3 inflammasome in the gut and lung

The nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family, pyrin domain-containing protein 3 (NLRP3) inflammasome, is one of the most well-characterized inflammasomes, activated by pathogen-associated molecular patterns and damage-associated molecular patterns, including from commensal or pathogenic bacterial and viral infections. The NLRP3 inflammasome promotes inflammatory cell recruitment and regulates immune responses in tissues such as the gastrointestinal tract and the lung, and is involved in many diseases that affect the gut and lung. Recently, the microbiome in the gut and the lung, and the crosstalk between these organs (gut-lung axis), has been identified as a potential mechanism that may influence disease in a bidirectional manner. In this review, we focus on themes presented in this area at the 2019 World Congress on Inflammation. We discuss recent evidence on how the microbiome can affect NLRP3 inflammasome responses in the gut and lung, the role of this inflammasome in regulating gut and lung inflammation in disease, and its potential role in the gut-lung axis. We highlight the exponential increase in our understanding of the NLRP3 inflammasome due to the synthesis of the NLRP3 inflammasome inhibitor, MCC950, and propose future studies that may further elucidate the roles of the NLRP3 inflammasome in gut and lung diseases.

Mesalazine-induced lung injury with severe respiratory failure successfully treated with steroids and non-invasive positive pressure ventilation

Drug-induced lung injury (DLI) has become more common because of the increasing number of therapeutic agents in use. Mesalazine, also known as 5-aminosalicylic acid (5-ASA), is one of the key drugs for the treatment of ulcerative colitis (UC). Although mesalazine-induced lung injury has been previously reported, few cases have included severe respiratory failure. In this report, we present a case of mesalazine-induced lung injury with severe respiratory failure, which was improved by discontinuation of mesalazine and introduction of corticosteroid therapy and ventilation support with non-invasive positive pressure ventilation (NPPV). We also review the previous literature on mesalazine-induced lung injury.

Predictors of mortality in inflammatory bowel disease patients treated for pneumonia

BACKGROUND

Community-acquired pneumonia is among the most common infections affecting ulcerative colitis and Crohn's disease patients. Data regarding epidemiology and outcomes of pneumonia in inflammatory bowel disease patients is lacking. We aimed to identify predictors of adverse outcomes among inflammatory bowel disease patients treated for pneumonia.

METHODS

This was a retrospective cohort study that included adult patients admitted to Sheba Medical Center for pneumonia between 2012 and 2018. Data was collected from an electronic repository of all emergency department admissions and included tabular demographic and clinical variables and free-text physician records. Pneumonia cases were extracted using the International Classification of Diseases (ICD-10) coding.

RESULTS

Of 16,732 admissions with pneumonia, 97 were inflammatory bowel disease patients (45 Crohn's disease; 52 ulcerative colitis). We found a similar rate of 30-day mortality among inflammatory bowel disease and non-inflammatory bowel disease patients (12.1% versus 11.3%, p = 0.824) and between Crohn's disease and ulcerative colitis patients (11.1% versus 11.5%, p = 0.947). There was an increased hospitalization rate among inflammatory bowel disease patients (92.8% versus 85.6%, p = 0.045), but similar hospitalization duration (4 versus 4 days, p = 0.384). Crohn's disease patients had a shorter hospitalization duration compared with ulcerative colitis patients (3 versus 5.5 days, p = 0.029). Bronchiectasis (adjusted odds ratio 60.95, 95% confidence interval 2.72-1364.39, p = 0.01) and opioids use (adjusted odds ratio 13.21, 95% confidence interval 1.29-135.18, p = 0.03) were associated with an increased 30-day mortality rate in inflammatory bowel disease patients.

CONCLUSION

This is the first study to identify predictors of mortality in inflammatory bowel disease patients with pneumonia. The rate of mortality and hospitalization duration of stay were similar among inflammatory bowel disease and non-inflammatory bowel disease patients. Use of opioids and presence of bronchiectasis were associated with a higher risk of mortality in inflammatory bowel disease patients with pneumonia.

Interstitial and Granulomatous Lung Disease in Inflammatory Bowel Disease Patients

BACKGROUND

Interstitial lung [ILD] disease and granulomatous lung disease [GLD] are rare respiratory disorders that have been associated with inflammatory bowel disease [IBD]. Clinical presentation is polymorphic and aetiology is unclear.

METHODS

This was an ECCO-CONFER project. Cases of concomitant ILD or GLD and IBD, or drug-induced ILD/GLD, were collected. The criteria for diagnosing ILD and GLD were based on definitions from the American Thoracic Society and the European Respiratory Society and on the discretion of reporting clinician.

RESULTS

We identified 31 patients with ILD. The majority had ulcerative colitis [UC] [n = 22]. Drug-related ILD was found in 64% of these patients, 25 patients [80.6%] required hospitalisation, and one required non-invasive ventilation. The causative drug was stopped in all drug-related ILD, and 87% of patients received systemic steroids. At follow-up, 16% of patients had no respiratory symptoms, 16% had partial improvement, 55% had ongoing symptoms, and there were no data in 13%. One patient was referred for lung transplantation, and one death from lung fibrosis was reported. We also identified 22 GLD patients: most had Crohn's disease [CD] [n = 17]. Drug-related GLD was found in 36% of patients and 10 patients [45.4%] required hospitalisation. The causative drug was stopped in all drug-related GLD, and 81% of patients received systemic steroids. Remission of both conditions was achieved in almost all patients.

CONCLUSIONS

ILD and GLD, although rare, can cause significant morbidity. In our series, over half of cases were drug-related and therefore focused pharmacovigilance is needed to identify and manage these cases.

Increased risk of idiopathic pulmonary fibrosis in inflammatory bowel disease: A nationwide study

BACKGROUND AND AIM

The relationship between inflammatory bowel disease (IBD) and idiopathic pulmonary fibrosis (IPF) remains unclear. We evaluated the risk for developing IPF in patients with IBD using a nationwide population-based study.

METHODS

Using claims data from the National Health Insurance service in Korea, patients with IBD, including Crohn's disease (CD) and ulcerative colitis (UC), were identified through both the 10th revision of the International Statistical Classification of Diseases and Related Health Problems and rare and intractable disease program codes from January 2010 to December 2013. We compared 38 921 IBD patients with age-matched and sex-matched individuals without IBD in a ratio of 1:3. Patients with newly diagnosed IPF were identified by both the 10th revision of the International Statistical Classification of Diseases and Related Health Problems and rare and intractable disease registration codes.

RESULTS

During a mean 4.9-year follow-up, the incidence of IPF in patients with IBD was 33.21 per 100 000 person-years. The overall risk of IPF was significantly higher in IBD patients than in non-IBD controls (hazard ratio [HR], 1.62; 95% confidence interval [CI], 1.20-2.20; P = 0.003). In patients with CD, the incidence (per 100 000 person-years) of IPF was 26.04; in controls, the incidence was 9.15 (HR, 2.89; 95% CI, 1.46-5.72; P = 0.002). The incidence of IPF in patients with UC tended to be higher than in controls (36.66 vs 26.54 per 100 000 person-years; 95% CI, 0.99-1.99; HR, 1.41; P = 0.066). The risk of developing IPF in patients with IBD was higher in male patients than in female patients (P = 0.093 in CD; P = 0.147 in UC by interaction analysis).

CONCLUSIONS

Patients with IBD, especially CD, have an increased risk of developing IPF.

Pulmonary Manifestations of Inflammatory Bowel Disease

Pulmonary manifestations of inflammatory bowel disease are increasingly recognized in patients with ulcerative colitis and Crohn's disease. Most commonly, incidental abnormalities are noted on chest imaging or pulmonary function tests. Although clinically significant pulmonary disease is less common, it can carry significant morbidity for patients. We review the presenting symptoms, workup, and management for several of the more common forms of inflammatory bowel disease-related pulmonary disease. Increased awareness of the spectrum of extraintestinal inflammatory bowel disease will help providers more readily recognize this phenomenon in their own patients and more comprehensively address the protean sequelae of inflammatory bowel disease.

Tracheobronchitis in ulcerative colitis: a case report of therapeutic response with infliximab and review of the literature

Background

The extra-intestinal manifestation of tracheobronchitis is a rare complication of ulcerative colitis (UC). Here, we present a case of UC-related tracheobronchitis wherein the positive clinical effects of infliximab are demonstrated.

Case presentation

We report the case of a 39-year old woman who presented with a chronic productive cough on a distant background of surgically managed ulcerative colitis (UC). Our patient failed to achieve a satisfactory clinical improvement despite treatment with high dose inhaled corticosteroids, oral corticosteroids and azathioprine. Infliximab therapy was commenced and was demonstrated to achieve macroscopic and symptomatic remission of disease.

Conclusions

We present the first case report documenting the benefits of infliximab in UC-related tracheobronchitis.

Lung inflammation and disease: A perspective on microbial homeostasis and metabolism

It is now well appreciated that the human microbiome plays a significant role in a number of processes in the body, significantly affecting its metabolic, inflammatory, and immune homeostasis. Recent research has revealed that almost every mucosal surface in the human body is associated with a resident commensal microbiome of its own. While the gut microbiome and its role in regulation of host metabolism along with its alteration in a disease state has been well studied, there is a lacuna in understanding the resident microbiota of other mucosal surfaces. Among these, the scientific information on the role of lung microbiota in pulmonary diseases is currently severely limited. Historically, lungs have been considered to be sterile and lung diseases have only been studied in the context of bacterial pathogenesis. Recently however, studies have revealed a resilient microbiome in the upper and lower respiratory tracts and there is increased evidence on its central role in respiratory diseases. Knowledge of lung microbiome and its metabolic fallout (local and systemic) is still in its nascent stages and attracting immense interest in recent times. In this review, we will provide a perspective on lung-associated metabolic disorders defined for lung diseases (e.g., chronic obstructive pulmonary disease, asthma, and respiratory depression due to infection) and correlate it with lung microbial perturbation. Such perturbations may be due to altered biochemical or metabolic stress as well. Finally, we will draw evidence from microbiome and classical microbiology literature to demonstrate how specific lung morbidities associate with specific metabolic characteristics of the disease, and with the role of microbiome in this context. © 2018 IUBMB Life, 71(1):152-165, 2019.

Chronic cough in a patient with stable ulcerative colitis: a rare but important extraintestinal manifestation of inflammatory bowel disease

A 74-year-old woman presented to her general practitioner with cough and occasional sputum production. Having failed to respond to courses of antibiotics in the community, she was referred to the thoracic medicine clinic. High-resolution CT chest revealed cylindrical bronchiectasis predominantly in the right lower lobe. Lung function revealed preserved FEV₁ and FVC but reduced gas transfer values. Bronchiectasis secondary to ulcerative colitis was diagnosed. Inhaled corticosteroid therapy was initiated, with good clinical response noted at 6 monthly follow-up. Remission was sustained with tapering of the steroid dose. Recognition of respiratory complications in cases of inflammatory bowel disease is likely still poor among clinicians. Although rare, a working knowledge of principles of investigation and management will aid timely diagnosis and treatment, potentially preventing progression of respiratory disease.

[Aspects of pulmonary involvement in inflammatory bowel disease]

The incidence of pulmonary manifestations of inflammatory bowel disease (IBD) appears to be much higher than previously assumed. In prospective studies, subclinical pulmonary interstitial infiltrates or pathological lung function were found in 40%-60% of IBD patients, both in children and adults. Pulmonary disorders can affect any part of the respiratory system, the most frequent pattern being inflammation of the large airways often associated with bronchiectasis. The differential diagnosis should include drug-related pulmonary disease and infectious causes when receiving immunosuppressive therapy. The diagnostic approach consists of a thorough history and clinical status as well as lung function tests including body plethysmography and high-resolution computed tomography of the thorax. Bronchoscopy with broncheoalveolar lavage and sample collection for histology as well as exclusion of pulmonary embolism may be indicated. Pulmonary disease in association with IBD can develop at any time during the course of IBD: in rare cases, symptoms can evolve even before gastrointestinal symptoms appear. On the other hand, there are frequent reports on the occurrence of pulmonary inflammation after proctocolectomy in patients with ulcerative colitis. The pathophysiologic background is largely unknown, but there seems to be an interaction between gastrointestinal and pulmonary inflammation. The mainstay of therapy are inhaled or systemic corticosteroids. Most patterns of pulmonary involvement in IBD respond well to corticosteroid therapy. Rarely, serious and persisting complications occur, such as strictures or stenosis of the large airways.

Chest High-resolution Computed Tomography Findings in 601 Patients with Inflammatory Bowel Diseases

RATIONALE AND OBJECTIVES

Pulmonary involvement in inflammatory bowel disease may reflect the common embryonic origin of the gastrointestinal tract and the bronchial tree. No studies have compared pulmonary high-resolution computed tomography (HRCT) findings between ulcerative colitis (UC) and Crohn disease (CD). This study aimed to assess the relationship between pulmonary HRCT findings and inflammatory bowel disease activity and to compare HRCT findings between UC and CD.

MATERIALS AND METHODS

We retrospectively identified 601 consecutive patients (350 with UC and 251 with CD) who had undergone chest HRCT examinations at our institutions between April 2004 and April 2016. Parenchymal abnormalities, enlarged lymph nodes, and pleural effusion were evaluated on HRCT.

RESULTS

One hundred sixty-seven patients (94 men, 73 women; aged 12-86 years, mean: 47.2 years) with UC and 93 patients (61 men, 32 women; aged 12-71 years, mean: 37.9 years) with CD had abnormal findings on chest HRCT. The HRCT findings of UC and CD mainly consisted of centrilobular nodules (in 49.1% and 45.2% of cases, respectively) and bronchial wall thickening (in 31.7% and 54.8%, respectively). There was no relationship between HRCT findings and disease activity. Bronchial wall thickening was significantly more frequent in patients with CD than in those with UC (P < .001).

CONCLUSION

The main chest HRCT findings in UC and CD are centrilobular nodules and bronchial wall thickening. There are differences in HRCT findings between UC and CD.

Exploring the microbiome in health and disease

The analysis of human microbiome is an exciting and rapidly expanding field of research. In the past decade, the biological relevance of the microbiome for human health has become evident. Microbiome comprises a complex collection of microorganisms, with their genes and metabolites, colonizing different body niches. It is now well known that the microbiome interacts with its host, assisting in the bioconversion of nutrients and detoxification, supporting immunity, protecting against pathogenic microbes, and maintaining health. Remarkable new findings showed that our microbiome not only primarily affects the health and function of the gastrointestinal tract but also has a strong influence on general body health through its close interaction with the nervous system and the lung. Therefore, a perfect and sensitive balanced interaction of microbes with the host is required for a healthy body. In fact, growing evidence suggests that the dynamics and function of the indigenous microbiota can be influenced by many factors, including genetics, diet, age, and toxicological agents like cigarette smoke, environmental contaminants, and drugs. The disruption of this balance, that is called dysbiosis, is associated with a plethora of diseases, including metabolic diseases, inflammatory bowel disease, chronic obstructive pulmonary disease, periodontitis, skin diseases, and neurological disorders. The importance of the host microbiome for the human health has also led to the emergence of novel therapeutic approaches focused on the intentional manipulation of the microbiota, either by restoring missing functions or eliminating harmful roles. In the present review, we outline recent studies devoted to elucidate not only the role of microbiome in health conditions and the possible link with various types of diseases but also the influence of various toxicological factors on the microbial composition and function.

Pulmonary function in patients with ulcerative colitis and its relationship with disease severity

Background and Aim

Ulcerative colitis (UC) patients have several extraintestinal and systemic manifestations. As studies on the frequency and predictors of pulmonary involvement in patients with UC are inconsistent, we undertook this prospective study.

Methods

Eighty-seven patients with UC (in remission 49, 56.3%, active disease 38, 43.6%, median age: 40 years, range: 16-66, 55, 62.2% males) and 50 healthy controls (median age: 38 years, range: 14-69, 34, 68% males) underwent pulmonary function tests (PFTs) including forced expiratory volume in 1 s (FEV₁), forced vital capacity (FVC), Tiffeneau value (FEV₁/FVC), mid-expiratory flow rate, and diffusion lung capacity for carbon monoxide with spirometer.

Results

Subjects with UC and control were comparable in age and gender. PFT was abnormal in 24 (27.5%) patients (active disease 15/38, 39.4%, remission 9/49, 18.4%) and 1 (2%) control (P < 0.005). Of the 24 patients with abnormal PFT, small airway, restrictive, and obstructive defects were detected in 12 (50%), 11 (45.8%), and 1 (4.2%) patients, respectively. Patients with abnormal PFT more often had active disease (15/24, 62.5% vs 23/63, 36.5%; P = 0.03). No relation of PFT abnormalities was found with age, sex, duration of disease, body mass index, serum albumin, and hemoglobin levels, and other extraintestinal manifestation (arthritis/arthralgia) and drugs used to treat UC.

Conclusion

UC patients with active disease have abnormal pulmonary functions with predominant involvement of small airways. Active UC was more often associated with abnormal PFT than the disease in remission.

Contributions of the intestinal microbiome in lung immunity

The intestine is a critical site of immune cell development that not only controls intestinal immunity but extra-intestinal immunity as well. Recent findings have highlighted important roles for gut microbiota in shaping lung inflammation. Here, we discuss interactions between the microbiota and immune system including T cells, protective effects of microbiota on lung infections, the role of diet in shaping the composition of gut microbiota and susceptibility to asthma, epidemiologic evidence implicating antibiotic use and microbiota in asthma and clinical trials investigating probiotics as potential treatments for atopy and asthma. The systemic effects of gut microbiota are partially attributed to their generating metabolites including short chain fatty acids, which can suppress lung inflammation through the activation of G protein-coupled receptors. Thus, studying the interactions between microbiota and immune cells can lead to the identification of therapeutic targets for chronic lower respiratory diseases.

Ulcerative colitis with acute pleurisy: A case report and review of the literature

RATIONALE

Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn's disease, are associated with a large number of extraintestinal manifestations. Pulmonary manifestations are infrequently seen in patients with IBD. Moreover, serositis including pleural and pericardial manifestations in UC is rare.

PATIENT CONCERNS

We report a case of UC with acute pleurisy in a 43-year-old man; review literature; and discuss the diagnosis, differential diagnosis, and treatment.

DIAGNOSES

Active duodenal ulcer was found using gastroscopy. Multiple ulcers in segmented pattern were noticed in the left hemi-colon using colonoscopy. An UC in active stage was confirmed subsequently by histology.

INTERVENTION

The patient was treated with bifidobacterium tetravaccine tablets, oral mesalazine and mesalazine enemas. The omeprazole and mucosal protective agents were given to treat the duodenal ulcer.

OUTCOMES

As follow-up, the therapy including oral mesalazine and infliximab regularly was continued and the patient condition was stabilized.

MAIN LESSON

Pulmonary involvement should be considered in patients who develop pleurisy in UC. Infliximab is considered the better available treatment for patients presenting with pleurisy in UC.

Cryptogenic Organizing Pneumonia With Lung Nodules Secondary to Pulmonary Manifestation of Crohn Disease

Crohn disease is an immune-mediated inflammatory condition with gastrointestinal and extraintestinal manifestations in patients. Pulmonary involvement of Crohn disease is one manifestation. There have been case reports which have shown Crohn disease and lung nodules which were noted to be histopathological as cryptogenic organizing pneumonia (COP). In our case, a 22-year-old woman with Crohn disease was seen with complaints of chest pain and cough. Computed tomographic scan of chest showed multiple bilateral lung nodules, for which biopsy was done, which showed COP. The case study is followed by a deeper discussion of COP and the extraintestinal manifestation seen in inflammatory bowel disease.

Pulmonary dysfunction in 114 patients with inflammatory bowel disease

This study aimed to investigate the pulmonary function in patients with inflammatory bowel disease (IBD) and its clinical feature and risk factors.One hundred fourteen patients with IBD and 120 healthy subjects were recruited. The medical information including general situation, biochemical examinations, lung function, and the treatment was recorded and analyzed.In 107 patients (107/114, 93.86%), lung function testing showed the pulmonary ventilation, residual volume, and pulmonary diffusion in IBD patients significantly increased as compared to controls (P < .05). No significant differences were observed between ulcerative colitis (UC) patients and Crohn disease (CD) patients (P > .05). However, the vital capacity, forced vital capacity, MVV, forced expiratory volume in first second, peak expiratory flow rate, and maximum mid-expiratory flow in IBD patients significantly decreased when compared with controls (P < .01). There was no significant correlation between pulmonary function and severity and extent of IBD. The chronicity of inflammation might probably reduce the possibility of developing pulmonary dysfunction, while the erythrocyte sedimentation rate (ESR) was found as a harmful factor for developing pulmonary dysfunction.The pulmonary function significantly decreases in IBD patients and is characterized by either simple restrictive/obstructive dysfunction or mixed. The pulmonary function of IBD patients has no relationship with the severity and extent of IBD. IBD combined with pulmonary dysfunction was imperceptible, and clinicians could consider performing pulmonary function testing for IBD patient as many as possible, especially for those who have high level of ESR or any respiratory symptoms like cough, in order to avoid severe pulmonary damage.