Haemoptysis, which is a challenging symptom accounting for 10-15% of all pulmonology consultations, may be associated with life-threatening medical conditions such as lung cancer [1-7]. Its aetiology and epidemiology vary widely among studies according to geographic locations and time of publication, epidemiological design, and diagnostic tests employed [2-8]. Bronchiectasis, malignancies, post-tuberculosis sequelae, and idiopathic bleedings have been recognised as the most frequent causes of haemoptysis in Europe over the last decade [3-7]. No guidelines exist suggesting an optimal work-up of symptoms, and data on the diagnostic yield of the most commonly prescribed examinations are limited [8]. The aim of this observational, prospective, multicentre study was to investigate the haemoptysis aetiology in association with its severity in an Italian population. We also evaluated the diagnostic yield of the prescribed diagnostic tests. The study was approved by the ethical committees of five Italian participating hospitals and registered at ClinicalTrials.gov (identifier: NCT02045394). Written informed consent was signed by the recruited patients, who were followed-up for 18 months. Herein, we report the findings of the baseline assessment. From July 2013 to September 2015, consecutive adult (i.e. ⩾18 years old) patients with haemoptysis were considered eligible. The following were considered as exclusion criteria: 1) aetiology of haemoptysis already detected (e.g. proven cancer-related and/or bronchiectasis-related haemoptysis); and 2) refusal to sign the informed consent. Patients were divided into three groups on the basis of the total amount of blood expectorated in 24 h [2, 3, 9]: mild (i.e. drops of blood to 20 mL in 24 h), moderate (i.e. 20-500 mL in 24 h), and severe (i.e. >500 mL in 24 h). All enrolled patients underwent physical examination and blood analysis. Subsequent tests deemed necessary for the diagnosis (i.e. sputum cultures, chest radiography, multi-detector chest computed tomography (CT), bronchoscopy, otorhinolaryngological evaluation, angiography) were chosen by the attending clinician on the basis of the clinical hypothesis and the symptom-driven diagnostic protocols of each hospital involved in the study. Final diagnosis was established in each centre, on the basis of the clinical and imaging evidence, by a multidisciplinary consensus that involved pulmonologists, radiologists, pathologists and otorhinolaryngologists. An electronic ad hoc form was created to collect demographic, epidemiological and clinical variables. Absolute and relative frequencies were used to summarise qualitative variables. Quantitative variables, for which the non-parametric distribution was assessed with the Shapiro-Wilk test, were summarised with medians and interquartile ranges (IQRs). 95% confidence intervals were computed to provide an interval estimation. The statistical software used for all the computations was Stata13.0 (StataCorp, College Station, TX, USA). During the study period, 606 patients (median age 67...
