Post-infectious Bronchiolitis Obliterans In Children: A Review Of 32 Cases

Background: Bronchiolitis obliterans is a kind of chronic airflow obstruction syndrome which is associated with small airway inflammatory injury.BO is usually confined to terminal bronchioles.BO is associated with infection,connective tissue disease,harmful substances inhaled,bone marrow and organ transplantation.After-infection,which is called Post-infectious bronchiolitis obliterans,is the main reason in children.This disease is common in lower respiratory tract infection.Virus infection in the most common.Similarly to other respiratory infections,the main clinical manifestations is anhelation,wheezing or coughing,the lung with dry and wet rale.HRCT can be seen with Mosaic perfusion,thickening and dilation of bronchial wall.Pulmonary function is mainly manifested as obstructive ventilation and mixed ventilation.There is no uniform standard for treatment,mainly using glucocorticoid,azithromycin and bronchodilatation.Although the application of HRCT has improved the diagnosis rate of BO.But the etiology is diverse,and there was no significant difference of clinical manifestation between BO and other respiratory infections.Lung biopsy as a limited diagnostic gold standard in clinical application,easy to cause misdiagnosis and missed diagnosis,and there is no standard treatment of the disease,once the small airway occlusion will be difficult to reverse.The overall prognosis of the disease is poor,affecting the healthy growth of children.Therefore,early detection,early diagnosis,early treatment is the key to prevent the progression of the disease.Objectives: This study aimed to observe the clinical characteristics,treatments and prognoses of 32 children with post-infectious Bronchiolitis obliterans(PIBO).And it provides a reference for the diagnosis and treatment of PIBO.Methods: Children diagnosed with PIBO were studied at the First Hospital of Jilin University of the first Pediatric respiratory department.Their clinical manifestation,HRCT,lung functions,treatments and prognoses were reported.Results: 32 children have recurrent or persistent cough,wheezing,there were 29 cases of fever,10 cases of dyspnea,5 cases of restricted movement,15 cases of positive tri-depression,32 cases of respiratory gain.On pulmonary auscultation,continuous rhonchi in the double lung were found in all of 32 cases,and moist rales were heared in 30 cases.32 cases underwent HRCT of lung,30 cases existed Mosaic perfusion signs(93.75%),10 cases appeared bronchial wall thickening(31.25%),8 cases(25%)manifested bronchiectasis,and atelectasis were found in 2 cases(6.25%).Twenty-seven patients performed lung functions.Lung function moisture analysis showed19 cases with obstructive ventilationdysfunction,1case with mixed ventilation dysfunction,VPEF/VE and TPTEF/TE were reduced.2 cases were showed increased peripheral airway resistance in Pulse shock tests,2 caseswith normal airway resistance.Pulmonaryventilationfunction examination showed FVC,FEV1,FEV1/FVC and FEF25%-75% lower.Bronchi relaxation test was negative in 1 case,2 cases werepositive.After the original diagnosis,every 2~4 weeks after discharge from hospital come to the hospital for review.23 cases were followed up successfully,clinical manifestations were improved significantly in 5 cases,improved in 17 cases poorly recovered in 1 case,and 1 case was dead.No one is completely cured..Lung CT were relieved in 6 cases.2 cases with lung shadows were not aggravating,1 case were still left Mosaic signs.13 cases of pulmonary function were still characterized by obstructive ventilation dysfunction,1 case was aggravating,1 case developed for mild hybrid ventilation dysfunction,no one was back to normal.The overall prognosis was good,but lung CT and pulmonary function had no obvious improvement.Conclusions: The main clinical manifestations of PIBO are cough,wheezing and dyspnea.On pulmonary auscultation,rhonchi and moist rales are found.Mosaic perfusion is the mainperformance of HRCT of PIBO.Pulmonary function may have different degrees of obstructive ventilatory dysfunction.