Konstantinos Kagouridis

Sleep oxygen desaturation predicts survival in idiopathic pulmonary fibrosis.

BACKGROUND Recent studies suggest poor sleep quality in patients with idiopathic pulmonary fibrosis (IPF). However, so far, the impact of IPF-related sleep breathing disorders (SBDs) on survival has not been extensively studied. METHODS In a cohort of 31 (24 males) treatment-naïve, newly diagnosed consecutive IPF patients, we prospectively investigated the relationship of SBD parameters such as apnea-hypopnea index (AHI), maximal difference in oxygen saturation between wakefulness and sleep (maxdiff SpO2), and lowest sleep oxygen saturation (lowest SpO2) with clinical (survival, dyspnea, daytime sleepiness), pulmonary function, submaximal (6-min walk test [6MWT]) and maximal exercise variables (cardiopulmonary exercise test [CPET]), and right ventricular systolic pressure (RVSP). RESULTS Sleep oxygen desaturation exceeded significantly that of maximal exercise (p < 0.001). Maxdiff SpO2 was inversely related to survival, DLCO%, and SpO2 after 6MWT, and directly with dyspnea, AHI, and RVSP. The lowest SpO2 was directly related to survival and to functional (TLC%, DLCO%) as well as submaximal and maximal exercise variables (6MWT distance, SpO2 after 6MWT, peak oxygen consumption/kg, SpO2 at peak exercise), while an inverse association with dyspnea score, AHI, and RVSP was observed. CONCLUSIONS Our findings provide evidence that intermittent sleep oxygen desaturation significantly exceeds that of maximal exercise and is associated with survival in IPF patients. Furthermore, they imply the existence of a link between lung damage and apnea events resulting to the induction and severity of intermittent sleep oxygen desaturation that aggravate pulmonary arterial hypertension and influence IPF survival.

Combined pulmonary fibrosis and emphysema

The advent of computed tomography permitted recognition of the coexistence of pulmonary fibrosis and emphysema (CPFE). Emphysema is usually encountered in the upper lobes preceding fibrosis of the lower lobes, and patients are smokers, predominantly male, with distinct physiologic profile characterized by preserved lung volumes and markedly reduced diffusion capacity. Actually, the term CPFE is reserved for the coexistence of any type and grade of radiological pulmonary emphysema and the idiopathic usual interstitial pneumonia computed tomography pattern as well as any pathologically confirmed case. CPFE is complicated by pulmonary hypertension, lung cancer and acute lung injury and may present different outcome than that of its components.

Patterns of airway involvement in inflammatory bowel diseases

Extraintestinal manifestations occur commonly in inflammatory bowel diseases (IBD). Pulmonary manifestations (PM) of IBD may be divided in airway disorders, interstitial lung disorders, serositis, pulmonary vasculitis, necrobiotic nodules, drug-induced lung disease, thromboembolic lung disease and enteropulmonary fistulas. Pulmonary involvement may often be asymptomatic and detected solely on the basis of abnormal screening tests. The common embryonic origin of the intestine and the lungs from the primitive foregut, the co-existence of mucosa associated lymphoid tissue in both organs, autoimmunity, smoking and bacterial translocation from the colon to the lungs may all be involved in the pathogenesis of PM in IBD. PM are mainly detected by pulmonary function tests and high-resolution computed tomography. This review will focus on the involvement of the airways in the context of IBD, especially stenoses of the large airways, tracheobronchitis, bronchiectasis, bronchitis, mucoid impaction, bronchial granulomas, bronchiolitis, bronchiolitis obliterans syndrome and the co-existence of IBD with asthma, chronic obstructive pulmonary disease, sarcoidosis and a1-antitrypsin deficiency.

The Role of Cardiopulmonary Exercise Test in IPF Prognosis

Background. In IPF, defects in lung mechanics and gas exchange manifest with exercise limitation due to dyspnea, the most prominent and disabling symptom. Aim. To evaluate the role of exercise testing through the 6MWT (6-minute walk test) and CPET (cardiopulmonary exercise testing) in the survival of patients with IPF. Methods. This is a prospective, observational study evaluating in 25 patients the relationship between exercise variables through both the 6MWT and CPET and survival. Results. By the end of the observational period 17 patients were alive (33% mortality). Observation ranged from 9 to 64 months. VE/VCO2 slope (slope of relation between minute ventilation and CO2 production), VO2 peak/kg (peak oxygen consumption/kg), VE/VCO2 ratio at anaerobic threshold, 6MWT distance, desaturation, and DLCO% were significant predictors of survival while VE/VCO2 slope and VO2 peak/kg had the strongest correlation with outcome. The optimal model for mortality risk estimation was VO2 peak/kg + DLCO% combined. Furthermore, VE/VCO2 slope and VO2 peak/kg were correlated with distance and desaturation during the 6MWT. Conclusion. The integration of oxygen consumption and diffusing capacity proved to be a reliable predictor of survival because both variables reflect major underlying physiologic determinants of exercise limitation.

Serologic evaluation in idiopathic interstitial pneumonias.

Purpose of reviewDiagnosis of idiopathic interstitial pneumonias (IIPs) requires the exclusion of, among others, concomitant connective tissue diseases (CTDs), which may present as interstitial lung disease (ILD). This review focuses on the evaluation required to separate these entities through serology, although not exclusively. Recent findingsSeveral recent data suggest that patients diagnosed with IIPs can show evidence of CTDs on follow-up. This is especially true for nonspecific interstitial pneumonia but may also be seen with other forms of ILD. SummaryILDs may occur alone, IIPs, or in association with, among others, CTDs. In the latter case, they may present before, during or even several months or years after the fulfillment of undisputed criteria for CTDs. If present before, their presentation presupposes their occurrence in early undiagnosed, undefined or undifferentiated CTD, which occasionally indefinitely maintains this status of diagnostic uncertainty, especially if ILD is empirically treated by immunosuppressants. Serologic evaluation for autoantibodies assisted by serum inflammatory biomarkers, detailed search for clinical clues of CTDs and suggestive histopathologic features on lung specimens may provide a framework to build the correct diagnosis. Obtaining a diagnosis of ILD associated with CTD exceeds semantics as this subset of patients may present different natural history, pathobiology, treatment and prognosis.

Pulmonary alveolar proteinosis: time to shift?

Pulmonary alveolar proteinosis (PAP) is categorized into hereditary, secondary and autoimmune PAP (aPAP) types. The common pathogenesis is the ability of the alveolar macrophages to catabolize phagocytized surfactant is affected. Hereditary PAP is caused by mutations involving the GM-CSF signaling, particularly in genes for the GM-CSF receptor and sometimes by GATA2 mutations. Secondary PAP occurs in hematologic malignancies, other hematologic disorders, miscellaneous malignancies, fume and dust inhalation, drugs, autoimmune disorders and immunodeficiencies. aPAP is related to the production of GM-CSF autoantibodies. PAP is characterized morphologically by the inappropriate and progressive ‘occupation’ of the alveolar spaces by an excessive amount of unprocessed surfactant, limiting gas exchange and gradually exhausting the respiratory reserve. Myeloid cells’ immunity deteriorates, increasing the risk of infections. Treatment of PAP is based on its etiology. In aPAP, recent therapeutic advances might shift the treatment option from the whole lung lavage procedure under general anesthesia to the inhalation of GM-CSF ‘as needed’.

Pirfenidone treatment in idiopathic pulmonary fibrosis: too much of a great expectation?

To the Editors: Idiopathic pulmonary fibrosis (IPF) is a dreadful, chronic and irreversibly progressive fibrosing disease lacking any effective treatment and leading to death in all affected patients [1, 2]. The scientific community is becoming aware that corticosteroids and immunosuppressors have failed to prove any efficacy concerning both mortality and the prevention of devastating complications, such as IPF acute exacerbations [1, 3]. Not only has this approach proven ineffective, but also harmful. Recently, the National Heart, Lung, and Blood Institute (Bethesda, MD, USA) aborted the continuation of treatment of combined prednisone, azathioprine and N -acetylcysteine (one arm of the three-arm multicentre PANTHER-IPF clinical trial) due to safety concerns [4]. The results of the interim analyses revealed that patients with IPF receiving the conventionally used triple-drug therapy consisting of prednisone, azathioprine and N -acetylcysteine had worse outcomes than those who received matched placebos. Thus, the need for an effective and safe treatment for IPF is still being pursued in several clinical trials. Pirfenidone (5-methyl-1-phenyl-2-[1H]-pyridone), a novel compound with anti-inflammatory, antifibrogenic and antioxidant properties, appears promising in IPF patients [1, 2 …

High levels of IL-6 and IL-8 characterize early-on idiopathic pulmonary fibrosis acute exacerbations

Introduction Controversy exists about the pathogenesis of idiopathic pulmonary fibrosis acute exacerbations (IPF‐AEs). According to one hypothesis IPF‐AEs represent the development of any etiology diffuse alveolar damage (DAD) upon usual interstitial pneumonia (UIP), whilst other researchers argue that an accelerated phase of the intrinsic fibrotic process of unknown etiology prevails, leading to ARDS. Different cytokines might be involved in both processes. The aim of this study was to assess pro‐inflammatory and pro‐fibrotic cytokines in the peripheral blood from stable and exacerbated IPF patients. Methods Consecutive IPF patients referred to our department were included. Diagnoses of IPF and IPF‐AE were based on international guidelines and consensus criteria. The interleukins (IL)‐4, IL‐6, IL‐8, IL‐10, and IL‐13 as well as active transforming growth factor‐beta (TGF‐&bgr;) were measured in blood from both stable and exacerbated patients on the day of hospital admission for deterioration. Subjects were followed for 12 months. Mann‐Whitney test as well as Tobit and logistic regression analyses were applied. Results Among the 41 patients studied, 23 were stable, and 18 under exacerbation; of the latter, 12 patients survived. The IL‐6 and IL‐8 levels were significantly higher in exacerbated patients (p = 0.002 and p = 0.046, respectively). An increase in either IL‐6 or IL‐8 by 1 pg/ml increases the odds of death by 5.6% (p = 0.021) and 6.7% (p = 0.013), respectively, in all patients. No differences were detected for the other cytokines. Conclusion High levels of IL‐6 and IL‐8 characterize early‐on IPF‐AEs and an increase in the levels of IL‐6 and IL‐8 associates with worse outcome in all patients. However, as the most representative pro‐fibrotic cytokines, TGF‐&bgr;, IL‐10, IL‐4 and IL‐13 were not increased and given the dualistic nature, both pro‐inflammatory and pro‐fibrotic of IL‐6 further studies are necessary to clarify the enigma of IPF‐AEs etiopathogenesis. HighlightsControversy exists about the pathogenesis of IPF‐AEs.Early in the development of an IPF‐AE, IL‐6 and IL‐8 blood levels are significantly increased.While TGF‐&bgr;, IL‐4, IL‐10, and IL‐13 levels show no difference compared stable IPF patients.Increased IL‐6 and IL‐8 levels are related to a higher risk of death in all IPF patients.Further studies are necessary to clarify the enigma of IPF‐AEs etiopathogenesis.

Idiopathic pulmonary fibrosis acute exacerbations: where are we now?

Considerable controversy is haunting the treatment of IPF ‘acute exacerbation’, its most devastating complication. The consensus coined term ‘acute exacerbation’ implies that on an unknown etiology disease such as IPF, an unknown etiology superimposed acute lung injury/acute respiratory distress syndrome (ALI/ARDS) represents the end-life event in a consistent proportion of patients and are treated by high dose steroids despite unproven benefit. Inversely, ALI/ARDS treatment recommendations are based on the provision of excellent supportive care plus an extensive search and appropriate treatment of the etiologic precipitant and all intensive care clinicians in the absence of an obvious etiology, considering that occult infection is the most probable and also the most treatable underlying condition, universally administer extensive spectrum antimicrobials. Viewing the persistent high mortality in IPF ‘acute exacerbations’ treated with steroids we strongly believe that a study comparing the two arms of the steroid and non-steroid approach is greatly awaited by scientists and owed to the patients.

Bronchiolitis: adopting a unifying definition and a comprehensive etiological classification

Bronchiolitis is an inflammatory and potentially fibrosing condition affecting mainly the intralobular conducting and transitional small airways. Secondary bronchiolitis participates in disease process of the airways and/or the surrounding lobular structures in the setting of several already defined clinical entities, mostly of known etiology, and occurs commonly. Primary or idiopathic bronchiolitis dominates and characterizes distinct clinical entities, all of unknown etiology, and occurs rarely. Secondary bronchiolitis regards infections, hypersensitivity disorders, the whole spectrum of smoking-related disorders, toxic fumes and gas inhalation, chronic aspiration, particle inhalation, drug-induced bronchiolar toxicities, sarcoidosis and neoplasms. Idiopathic or primary bronchiolitis defines clinicopathologic entities sufficiently different to be designated as separate disease entities and include cryptogenic constrictive bronchiolitis, diffuse panbronchiolitis, diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, neuroendocrine hyperplasia in infants, bronchiolitis obliterans syndrome in lung and allogeneic hematopoietic cell transplantation, connective tissue disorders, inflammatory bowel disease and bronchiolitis obliterans organizing pneumonia. Most of the above are pathological descriptions used as clinical diagnosis. Acute bronchiolitis, though potentially life threatening, usually regresses. Any etiology chronic bronchiolitis contributes to morbidity and/or mortality if it persists and/or progresses to diffuse airway narrowing and distortion or complete obliteration. Bronchiolitis in specific settings leads to bronchiolectasis, resulting in bronchiectasis.