Introduction: Bronchiolitis is a frequent infectious disease in children under two years of age. The number of cases increases during the rainy season and in young children with risk factors such as low birth weight, prematurity, and bronchopulmonary dysplasia. Not enough evidence is available in our setting on the frequency and the characteristics of pediatric emergency readmissions in the medium and long term, due to respiratory complications in patients diagnosed with bronchiolitis. Methodology: Descriptive, analytic study with a 24-month follow-up of a cohort of patients under two years of age and a first diagnosis of bronchiolitis. Probabilistic sample, inclusion of patients who came to the pediatric ER at a high complexity institution in Bogota city (Colombia) between 2008 and 2013. Risk factors, clinical and laboratory data with frequency measures and central trend analysis were studied. The first readmission to the ER due to Bronchial obstructive syndrome (BOS), presumptive asthma and pneumonia was analyzed. Results: A total of 298 children were included and followed in the cohort for two years; average age 4.3 months. Body weight less than 2500 gr (11.7%), prematurity (7%), parents with asthma (6.7%). Evolution of symptoms prior to admission >48 hours (64.4%). The most frequently prescribed laboratory tests were viral panel (69.1%), CBC (52.6%), and chest X-ray (68.4%). 1.3% had to be admitted at the Pediatric Intensive Care Unit (PICU). The primary management approach was oxygen therapy 93.6%. The Respiratory Syncytial Virus (RSV) was identified in 55.8% of the viral panel samples. The bronchial obstructive syndrome (BOS) was the principal reason for re-admission (24%) in the evening and affected mostly children younger than 6 months old. The number of admissions increased during the rainy season throughout the follow-up period. The probability of readmission due to BOS was 64.8% during the first year and there were no statistically significant differences when comparing readmissions due to other respiratory pathologies. Conclusions: RSV is the most frequently isolated agent despite the circulation of other pathogens. There is variability in the use of diagnostic aids and treatment showing poor compliance with the management guidelines. Oxygen and hydration therapy are the cornerstone of treatment.