Effect of azithromycin on patients with diffuse panbronchiolitis: retrospective study of 51 cases

Delivering macrolide antibiotics to heal a broken heart - And other inflammatory conditions

Drug carriers to deliver macrolide antibiotics, such as azithromycin, show promise as antibacterial agents. Macrolide drug carriers have largely focused on improving the drug stability and pharmacokinetics, while reducing adverse reactions and improving antibacterial activity. Recently, macrolides have shown promise in treating inflammatory conditions by promoting a reparative effect and limiting detrimental pro-inflammatory responses, which shifts the immunologic setpoint from suppression to balance. While macrolide drug carriers have only recently been investigated for their ability to modulate immune responses, the previous strategies that deliver macrolides for antibacterial therapy provide a roadmap for repurposing the macrolide drug carriers for therapeutic interventions targeting inflammatory conditions. This review describes the antibacterial and immunomodulatory activity of macrolides, while assessing the past in vivo evaluation of drug carriers used to deliver macrolides with the intention of presenting a case for increased effort to translate macrolide drug carriers into the clinic.

A determination of pan-pathogen antimicrobials?

While antimicrobial drug development has historically mitigated infectious diseases that are known, COVID-19 revealed a dearth of ‘in-advance’ therapeutics suitable for infections by pathogens that have not yet emerged. Such drugs must exhibit a property that is antithetical to the classical paradigm of antimicrobial development: the ability to treat infections by any pathogen. Characterisation of such ‘pan-pathogen’ antimicrobials requires consolidation of drug repositioning studies, a new and growing field of drug discovery. In this review, a previously-established system for evaluating repositioning studies is used to highlight 4 therapeutics which exhibit pan-pathogen properties, namely azithromycin, ivermectin, niclosamide, and nitazoxanide. Recognition of the pan-pathogen nature of these antimicrobials is the cornerstone of a novel paradigm of antimicrobial development that is not only anticipatory of pandemics and bioterrorist attacks, but cognisant of conserved anti-infective mechanisms within the host-pathogen interactome which are only now beginning to emerge. Ultimately, the discovery of pan-pathogen antimicrobials is concomitantly the discovery of a new class of antivirals, and begets significant implications for pandemic preparedness research in a world after COVID-19.

Good's syndrome with diffuse panbronchiolitis as the prominent manifestation: A case and literature review

Good's syndrome (GS) is characterized by thymoma combined with adult-onset immunodeficiency. Diffuse panbronchiolitis (DPB) is a chronic inflammatory airway disease, which predominantly affects East Asians. Japanese scholars have reported extensively about GS combined with DPB or DPB-like pulmonary manifestation. However, such reports are rare in China. We report here a case of GS in China with DPB as the prominent manifestation and carry out a literature review accordingly. Our review indicates that in adults with DPB-like clinical manifestations, thymic lesions should be excluded and related immune function tests should be performed to exclude GS to avoid missed diagnosis and misdiagnosis.

Immunomodulatory Effects of Azithromycin Revisited: Potential Applications to COVID-19

The rapid advancement of the COVID-19 pandemic has prompted an accelerated pursuit to identify effective therapeutics. Stages of the disease course have been defined by viral burden, lung pathology, and progression through phases of the immune response. Immunological factors including inflammatory cell infiltration and cytokine storm have been associated with severe disease and death. Many immunomodulatory therapies for COVID-19 are currently being investigated, and preliminary results support the premise of targeting the immune response. However, because suppressing immune mechanisms could also impact the clearance of the virus in the early stages of infection, therapeutic success is likely to depend on timing with respect to the disease course. Azithromycin is an immunomodulatory drug that has been shown to have antiviral effects and potential benefit in patients with COVID-19. Multiple immunomodulatory effects have been defined for azithromycin which could provide efficacy during the late stages of the disease, including inhibition of pro-inflammatory cytokine production, inhibition of neutrophil influx, induction of regulatory functions of macrophages, and alterations in autophagy. Here we review the published evidence of these mechanisms along with the current clinical use of azithromycin as an immunomodulatory therapeutic. We then discuss the potential impact of azithromycin on the immune response to COVID-19, as well as caution against immunosuppressive and off-target effects including cardiotoxicity in these patients. While azithromycin has the potential to contribute efficacy, its impact on the COVID-19 immune response requires additional characterization so as to better define its role in individualized therapy.

Expert recommendations on the role of macrolides in chronic respiratory diseases

Background:

India contributes to 32% of the total global disability-adjusted life years, due to chronic respiratory diseases. This has led to a high rate of health loss from these diseases. Antibiotics are commonly used in the management of respiratory disorders. With excellent tissue penetration, prolonged tissue persistence, and favorable side effect profile, macrolides are one of the best treatment options being recommended for respiratory, urogenital, dermal, and other bacterial infections. Still, there is a lack of clinical trial data on the use of macrolides in the management of respiratory chronic disease, and hence, there is a need for clinical guidance on their use in Indian setting.

Methods:

A systematic review of the literature was conducted on PubMed, Cochrane database, and Google Scholar. Existing guidelines, meta-analyses, systematic reviews, randomized controlled trials (RCTs), non-RCTs, landmark studies, and key-cited articles were selected. Recommendations were based on available evidence and expert panel's logical empiricism and consensus.

Results and Discussion:

This article discusses evidence-based and clinical practice based management of chronic respiratory conditions including chronic obstructive pulmonary disease, asthma, bronchiectasis, diffusive panbronchiolitis, and organizing pneumonia. The authors reviewed different respiratory conditions, role of macrolides in their management, adverse events and antimicrobial resistance associated with macrolides, evidence review of various clinical trials, guideline recommendations, and clinical recommendations.

Azithromycin prophylaxis after lung transplantation is associated with improved overall survival

BACKGROUND

Azithromycin prophylaxis (AP) in lung transplant recipients has been shown to reduce the composite end-point of death or chronic lung allograft dysfunction (CLAD) onset but without a clear effect on overall survival. Our program began using AP in 2010. We sought to evaluate the association between AP and survival and the risk of CLAD and baseline lung allograft dysfunction (BLAD).

METHODS

We studied double lung recipients transplanted between 2004 and 2016. We defined AP as chronic use of azithromycin initiated before CLAD onset. We analyzed the association between AP and death or retransplant using Cox regression with adjustment for potential confounders. We further used Cox and logistic models to assess the relationship between AP and post-transplant CLAD onset and BLAD, respectively.

RESULTS

A total of 445 patients were included, and 344 (77%) received AP (median time from transplant: 51 days). Patients receiving AP were more likely to receive induction with interleukin-2 receptor antagonists (57% vs 35%; p < 0.001). AP was associated with improved survival (hazard ratio [HR]: 0.59; 95% confidence interval [CI]: 0.42-0.82; p = 0.0020) in our fully adjusted model, with a reduced adjusted risk of BLAD (odds ratio: 0.53; 95% CI: 0.33-0.85; p = 0.0460) but no clear reduction in the adjusted risk of CLAD (HR: 0.69; 95% CI: 0.47-1.03; p = 0.0697).

CONCLUSIONS

AP is associated with improved survival after lung transplantation, potentially through improved baseline function. These findings build on prior trial results and suggest that AP is beneficial for lung transplant recipients.

Diffuse panbronchiolitis: A progressive fatal lung disease that is curable with azithromycin, but only if diagnosed!

Diffuse panbronchiolitis (DPB) is a rare progressive and eventually fatal pulmonary disease first identified in Japan and initially seen predominantly in Southeast Asia. Macrolide antibiotics rapidly reverse symptoms and pathology, and their use increased the 5 and 10-year survival from 50 and 30 percent, respectively, to over 90%. Review of 181 case reports from previous publications found patients with DPB commonly had their pulmonary symptoms preceded by rhinosinusitis, frequently by many years. Long delays in diagnosis for many years were common. The review further identified DPB in all ethnic groups and multiple areas outside of Southeast Asia. Although diagnosis was most commonly made in adults, 13% of the diagnoses were made in children and nine of the adult cases described onset in childhood. Few cases of relapse were reported, but extended periods of monitoring after treatment were not generally present.

Prognostic Value of Concomitant Bronchiectasis in Newly Diagnosed Diffuse Panbronchiolitis Patients on a Maintenance Therapy with Macrolides

Background

Factors determining the prognosis of diffuse panbronchiolitis (DPB) remain unclear at present. The objective of this study was to identify the prognostic value of concomitant bronchiectasis in the macrolide treatment efficacy and exacerbation risk in DPB patients.

Methods

Data of patients initially diagnosed with DPB at the Shanghai Pulmonary Hospital between January 2007 and December 2017 were retrospectively collected and analyzed. The patients were divided into two groups according to the existence of bronchiectasis. Clinical manifestations, laboratory findings, microbiological culture results, as well as exacerbation risks and treatment outcomes, were compared between these two groups. The survival curve and Cox regression analysis models were additionally constructed to further demonstrate the predicting role of bronchiectasis in DPB exacerbation.

Results

Baseline data revealed more respiratory symptoms, lower body mass index (BMI), and forced expiratory volume in one second (FEV1) as well as increased isolates of Pseudomonas aeruginosa (P. aeruginosa) in DPB subjects with bronchiectasis than those without. Furthermore, bronchiectasis was associated with a lower rate of responsiveness to macrolides and increased exacerbation frequency during follow-up. The survival curve and Cox regression analysis showed that comorbid bronchiectasis was linked to increased time to episode relapse, which remained significant even after controlling for BMI, FEV1, and P. aeruginosa culture results.

Conclusion

The coexistence of bronchiectasis predicted a poor outcome of maintenance macrolide therapy and an increased exacerbation risk in DPB subjects, possibly through its impacts on nutritional status, pulmonary function, and P. aeruginosa infections.

Inhibitory effects of azithromycin on the adherence ability of Porphyromonas gingivalis

BACKGROUND

Porphyromonas gingivalis is a major pathogen and has a high detection rate in periodontal disease. Fimbriae and hemagglutinin are expressed by P. gingivalis, and these play an important role in the adherence of the bacteria to periodontal tissue and biofilm formation. The aim of this study was to investigate the effects of sub-minimal inhibitory concentrations (sub-MICs) of azithromycin on the adherence of P. gingivalis, focusing on the inhibition of fimbriae expression and hemagglutinin activity.

METHODS

P. gingivalis ATCC 33277 were incubated anaerobically with sub-MICs of azithromycin at 37°C by gentle shaking for 18 hours. The bacterial cells were harvested, washed twice with phosphate-buffered saline (PBS), and the proteins analyzed by 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting. Adherence assay and hemagglutinin activity tests were done with the same culture.

RESULTS

The results of SDS-PAGE indicated that the sub-MICs of azithromycin inhibited 41-kDa fimbrial protein expression and hemagglutinin activities. The disappearance of 41-kDa fimbrial protein expression and long fimbriae in 0.4 µg/mL, 0.2 µg/mL, and 0.1 µg/mL of azithromycin was confirmed by western blotting and transmission electron microscopy. The adherence of P. gingivalis to human gingival epithelial cells was reduced by sub-MICs of azithromycin compared with the adherence levels without antibiotic.

CONCLUSIONS

These results suggest that sub-MICs of azithromycin may reduce the adherence of P. gingivalis to host cells, by inhibiting production of fimbriae and hemagglutinin activities. Therefore, azithromycin can be used as a biofilm treatment of periodontal disease caused by P. gingivalis.

Azithromycin treats diffuse panbronchiolitis by targeting T cells via inhibition of mTOR pathway

Azithromycin (AZM), that is a macrolide antibiotic, has been found to treat diffuse panbronchiolitis (DPB) effectively. However, the mechanism of action underlying the therapeutic effects remains unclear. We selected 64 patients with DPB from 305 patients who were diagnosed with DPB at the outpatient clinic in Shanghai Pulmonary Hospital from Jan 2010 to Oct 2014. The primary PBLs, CD4 + T cells, and Jurkat T cells were treated with AZM or erythromycin (EM), and the effects of AZM and EM on IL-17A and CXCL-2 production, proliferation, apoptosis and autophagy were evaluated. AZM and EM significantly inhibited IL-17A and CXCL-2 production in patients' PBLs (all P < 0.05). AZM significantly inhibited proliferation and promoted apoptosis of T cells from DPB patients. AZM can enhance autophagosome formation of T cells by suppressing S6RP phosphorylation, which is a downstream target of mTOR pathway (all P < 0.05). AZM and EM significantly decreased secreted IL-17A levels (P < 0.05) in the primary CD4 + T cells of patients with DPB. AZM may treat DPB patients by targeting cytokine production, proliferation, apoptosis and autophagy of T cell. The mechanism of therapeutic effects of AZM on DPB may be associated with a specific inhibition of mTOR pathway in the T lymphocytes.

The development of diffuse panbronchiolitis during the treatment with long-term, low-dose clarithromycin for chronic sinusitis

Diffuse panbronchiolitis (DPB) is a progressive inflammatory airway disease characterized by a chronic cough, copious sputum expectation, dyspnea, and chronic sinusitis. Owing to the long-term treatment of low-dose macrolides, the prognosis has been remarkably improved. However, in some cases, patients are refractory to macrolides, and the subsequent treatment strategies are controversial. We herein present a patient with the onset of DPB during treatment with long-term, low-dose clarithromycin (CAM) for chronic sinusitis who was successfully treated by switching to long-term treatment with normal-dose CAM. We should recognize that DPB may develop in patients with chronic sinusitis despite treatment with a long-term, low-dose macrolide. We also propose that increasing the dose of macrolide may be a useful strategy for treating refractory patients.

Autoinflammatory disease in the lung

Ascertaining the dominant cell type driving an immunological disease is essential to understanding the causal pathology and, therefore, selecting or developing an effective treatment. Classifying immunological diseases in this way has led to successful treatment regimens for many monogenic diseases; however, when the dominant cell type is unclear and there is no obvious causal genetic mutation, then identifying the correct disease classification and appropriate therapy can be challenging. In this review we focus on pulmonary immunological diseases where an innate immune signature has been identified as a predominant aspect of the immunopathology. We describe the molecular pathology of 'autoinflammatory diseases of the lung' and propose that small molecule and biological therapies, including recombinant interleukin-1 receptor antagonist, that target key innate immune pathways, are likely be beneficial in the control of pulmonary and systemic inflammation in these conditions. In addition, the successful use of macrolide antibiotics to treat lung infections in these conditions further confirms that the innate immune system is the key conductor of inflammation in these pulmonary diseases, as there is a strong body of evidence that macrolides are able to modulate the NLRP3 inflammasome and interleukin-1β and interleukin-18 secretion, both of which are central players in the innate immune response. Throughout this review we highlight the published evidence of autoinflammatory disease in chronic obstructive pulmonary disease, bronchiectasis, cystic fibrosis and rheumatoid lung disease and suggest that the fundamental pathology of these diseases places them towards the autoinflammatory pole of the immunological disease continuum.

Macrolides in Children With Community-Acquired Pneumonia: Panacea or Placebo?

Pneumonia, most often caused by a respiratory virus, is common in childhood. Mycoplasma pneumoniae also is detected frequently, particularly in older children in the era of pneumococcal conjugate vaccination. Despite recommendations for β-lactam antibiotics, macrolide antibiotics, including erythromycin, clarithromycin, and azithromycin, are prescribed frequently to children with acute lower respiratory infection. However, the significance of detecting "atypical" pathogens, including M pneumoniae, in children remains contentious. Considering the potential for antibacterial and anti-inflammatory activities of macrolides, our understanding of the role of these drugs in acute and chronic infections and in inflammatory conditions is changing. Some observational data have revealed improved outcomes in adults and children with pneumonia who are prescribed macrolides, although its widespread use has led to increases in macrolide resistance in Streptococcus pneumoniae and M pneumoniae. Clinical trials to define the role of macrolides in pediatric acute respiratory infection must be prioritized.

Azithromycin decreases NALP3 mRNA stability in monocytes to limit inflammasome-dependent inflammation

Background

Azithromycin, an antibiotic used for multiple infectious disorders, exhibits anti-inflammatory effects, but the molecular basis for this activity is not well characterized. Azithromycin inhibits IL-1β-mediated inflammation that is dependent, in part, on inflammasome activity. Here, we investigated the effects of azithromycin on the NACHT, LRR, and PYD domains-containing protein 3 (NALP3) protein, which is the sensing component of the NALP3 inflammasome, in human monocytes.

Methods

THP-1 cells were treated with azithromycin alone, LPS alone, or both. NALP3 and IL-1β protein levels were determined by immunoblotting. NLRP3 gene (encoding NALP3) transcript levels were determined by quantitative qPCR. In order to measure NLRP3 transcript decay, actinomycin D was used to impair gene transcription. THP-1 Lucia cells which contain an NF-κB responsive luciferase element were used to assess NF-κB activity in response to azithromycin, LPS, and azithromycin/LPS by measuring luminescence. To confirm azithromycin’s effects on NLRP3 mRNA and promoter activity conclusively, HEK cells were lipofected with luciferase reporter constructs harboring either the 5’ untranslated region (UTR) of the NLRP3 gene which included the promoter, the 3’ UTR of the gene, or an empty plasmid prior to treatment with azithromycin and/or LPS, and luminescence was measured.

Results

Azithromycin decreased IL-1β levels and reduced NALP3 protein levels in LPS-stimulated THP-1 monocytes through a mechanism involving decreased mRNA stability of the NALP3 – coding NLRP3 gene transcript as well as by decreasing NF-κB activity. Azithromycin accelerated NLRP3 transcript decay confirmed by mRNA stability and 3’UTR luciferase reporter assays, and yet the antibiotic had no effect on NLRP3 promoter activity in cells containing a 5’ UTR reporter.

Conclusions

These studies provide a unique mechanism whereby azithromycin exerts immunomodulatory actions in monocytes by destabilizing mRNA levels for a key inflammasome component, NALP3, leading to decreased IL-1β-mediated inflammation.

Immunomodulatory indications of azithromycin in respiratory disease: a concise review for the clinician

Azithromycin has a well-characterized bacteriostatic activity. However, it also has a robust immunomodulatory effect that has proven beneficial in a variety of chronic illnesses. This effect results in decreased production of pro-inflammatory cytokines in the acute phase and promotes resolution of chronic inflammation in the later phases. Specifically, azithromycin has direct activity on airway epithelial cells to maintain their function and reduce mucus secretion. These characteristics have resulted in the use of azithromycin in the management of a variety of chronic lung diseases including chronic obstructive pulmonary disease, cystic fibrosis (CF), non-CF bronchiectasis, bronchiolitis obliterans syndrome, diffuse panbronchiolitis, and asthma. In this review, we present the evidence supporting the role of azithromycin in these conditions with an emphasis on the clinical aspects for the practicing physician.

Comorbidities in interstitial lung diseases

Fibrosing lung disorders include a large number of diseases with diverse behaviour. Patients can die because of the progression of their illness, remain stable or even improve after appropriate treatment has been instituted. Comorbidities, such as acute and chronic infection, gastro-oesophageal reflux, pulmonary hypertension, lung cancer, cardiovascular diseases, and obstructive sleep apnoea, can pre-exist or develop at any time during the course of the disease and, if unidentified and untreated, may impair quality of life, impact upon the respiratory status of the patients, and ultimately lead to disease progression and death. Therefore, early identification and accurate treatment of comorbidities is essential.

Diffuse panbronchiolitis in a 10-year-old boy

Diffuse panbronchiolitis is a progressive fatal respiratory disease of unknown cause seen predominantly in Southeast Asian adults. We report this condition in a 10-year-old child of Korean birth because of the uncommon presentation at this age and the favorable outcome associated with early diagnosis. Our objective was also to demonstrate the gradual but complete resolution of the disease and sustained remission from early institution of azithromycin.

A prospective randomly controlled clinical trial on azithromycin therapy for induction treatment of children with nephrotic syndrome

A prospective study was designed to evaluate the efficacy of azithromycin (AZM) when combined with prednisone therapy compared with prednisone therapy alone in children with primary nephrotic syndrome (PNS) undergoing induction treatment. A prospective randomly controlled clinical trial was conducted. Randomization was performed to select the research subjects who were composed of children with PNS and treated with AZM combined with prednisone (the intervention group) and with prednisone alone (the control group). A total of 211 randomly selected patients with PNS received either AZM combined with prednisone (n = 106) or prednisone alone (n = 105) for 6 months. At three months in the follow-up period, 12 patients were lost to follow up (intervention group, 7; control group, 5), and 6 patients had a transient hypocomplementemia (intervention group, 4 ; control group, 2). AZM was administered at a dose of 10 mg/kg q.d (1 dose per day) for three consecutive days. The median duration before remission was 6 days in the intervention group and 9 days in the control group (p < 0.0001). Relapse rate differed among the groups at 3 months (11.6 vs. 21.4 %, p = 0.049). No difference in relapse rate was observed between the two groups within 4 to 6 months and at 6 months (p = 0.168, 0.052). After 4 weeks of treatment, steroid resistance occurred in 1 out of 95 (1.05 %) patients in the intervention group and in 10 out of 98 (10.2 %) patients in the control group (p = 0.006). After 8 weeks of treatment, no difference was found in steroid resistance between two groups (1/95 vs. 3/98, p = 0.327). During follow-up at 6 months, no difference was exhibited by the two groups on frequent relapse rates (p = 0.134).

CONCLUSION

If a course of AZM is added to the glucocorticoid-induced treatment among children with PNS, then the sensitivity of prednisone increases. This increase consequently reduces duration to remission and decreases relapse. However, further studies are necessary to confirm these results.

Azithromycin: mechanisms of action and their relevance for clinical applications

Azithromycin is a macrolide antibiotic which inhibits bacterial protein synthesis, quorum-sensing and reduces the formation of biofilm. Accumulating effectively in cells, particularly phagocytes, it is delivered in high concentrations to sites of infection, as reflected in rapid plasma clearance and extensive tissue distribution. Azithromycin is indicated for respiratory, urogenital, dermal and other bacterial infections, and exerts immunomodulatory effects in chronic inflammatory disorders, including diffuse panbronchiolitis, post-transplant bronchiolitis and rosacea. Modulation of host responses facilitates its long-term therapeutic benefit in cystic fibrosis, non-cystic fibrosis bronchiectasis, exacerbations of chronic obstructive pulmonary disease (COPD) and non-eosinophilic asthma. Initial, stimulatory effects of azithromycin on immune and epithelial cells, involving interactions with phospholipids and Erk1/2, are followed by later modulation of transcription factors AP-1, NFκB, inflammatory cytokine and mucin release. Delayed inhibitory effects on cell function and high lysosomal accumulation accompany disruption of protein and intracellular lipid transport, regulation of surface receptor expression, of macrophage phenotype and autophagy. These later changes underlie many immunomodulatory effects of azithromycin, contributing to resolution of acute infections and reduction of exacerbations in chronic airway diseases. A sub-group of post-transplant bronchiolitis patients appears to be sensitive to azithromycin, as may be patients with severe sepsis. Other promising indications include chronic prostatitis and periodontitis, but weak activity in malaria is unlikely to prove crucial. Long-term administration of azithromycin must be balanced against the potential for increased bacterial resistance. Azithromycin has a very good record of safety, but recent reports indicate rare cases of cardiac torsades des pointes in patients at risk.

The effects of azithromycin on patients with diffuse panbronchiolitis: a retrospective study of 29 cases

BACKGROUND

Diffuse panbronchiolitis (DPB), a chronic inflammatory disease of the airway, is treated with macrolide antibiotics. The ability of azithromycin to improve DPB prognosis, as detected by high-resolution computed tomography (HRCT) scans and lung function tests, has not been studied in a large retrospective of patients. Our study aims to investigate the effects of azithromycin on patients with DPB using lung function tests and radiologic images.

METHODS

Twenty-nine patients with DPB were studied; their medical records were collected and analyzed retrospectively. Patients studied were hospitalized in the respiratory department of the Yixing Hospital, affiliated with Jiangsu University. Azithromycin was administered for 6-17 months. Changes in lung function and HRCT scans after treatment with azithromycin for six months were compared with pre-treatment values and images respectively.

RESULTS

Azithromycin therapy for six months resulted in rapid improvements in lung function, demonstrated by forced expiratory volume in one second (FEV1.0%), forced expiratory volume in one second over the forced vital capacity (FEV1.0/FVC), and forced expiratory volume with 75% vital capacity (FEF75%) values. In addition, improvements were seen in small nodular shadows, dilated peripheral bronchi, bronchial wall thickening, and tree-in-bud pattern, as detected by chest HRCT scans.

CONCLUSIONS

Long-term therapy with azithromycin is effective for patients with DPB.

Diffuse parenchymal lung disease caused by surfactant deficiency: dramatic improvement by azithromycin

Pulmonary surfactant deficiency caused by mutations in ABCA3 (ATP-binding cassette transporter of the A subfamily, member 3) gene results in diffuse parenchymal lung disease (DPLD) in children. So far, systemic steroids are the main treatment, with however limited efficacy. We report the case of a young boy showing a dramatic long-term improvement of respiratory disease by low-dose azithromycin (AZM) with no side effect after 6 years of treatment. Cellular and molecular studies are ongoing to progress in the understanding of the mechanisms involved. On behalf of the National Reference Center for rare lung diseases in France (Respirare, http://www.respirare.fr), clinical studies on AZM in various forms of DPLD in children have been initiated and should provide information on the types of paediatric DPLD that may benefit from this treatment.

Bronchiolitis

Bronchiolitis is a disease of the small airways accompanied by progressive and often irreversible airflow obstruction. Bronchiolitis can have several causes such as infection, toxic exposure, collagen vascular disease, post lung and stem cell transplant, and idiopathic etiology. Symptoms of cough and sputum production are often mistaken for chronic obstructive pulmonary disease or asthma, leading to a delay in diagnosis. Unfortunately, many types of bronchiolitis do not improve with therapy. Bronchiolitis following lung and stem cell transplant are the most common types seen in adults, and provide important insights into its pathogenesis.

Immunomodulatory effects of antimicrobial agents. Part I: antibacterial and antiviral agents

Despite impressive therapeutic progresses in the battle against infections, microorganisms are still a threat to mankind. With hundreds of antibacterial molecules, major concerns remain about the emergence of resistant and multidrug-resistant pathogens. On the other hand, the antiviral drug armamentarium is comprised of only a few dozens of compounds which are highly pathogen specific, and resistance is also a concern. According to Arturo Casadevall (Albert Einstein College of Medicine, NY, USA), we have now entered the third era of anti-infective strategy, which intends to favor the interplay between active molecules and the immune system. The first part of this review focuses on the potential immunomodulating properties of anti-infective agents, beginning with antibacterial and antiviral agents.