Risk factors and clinical features for pulmonary paragonimiasis-associated pneumothorax

BackgroundPulmonary paragonimiasis, a food-borne zoonotic helminthiasis, is a parasitic disease of the lung caused by infection with trematodes species of the genus Paragonimus. Although pneumothorax has been reported as occuring with paragonimiasis, to date no study has been performed concerning the clinical features and predictive risk factors for this condition.MethodsThis retrospective study, which aims to fill this gap, was conducted at Jeonbuk National University Hospital. All patients (aged >= 19 years) were diagnosed with paragonimiasis between May 2011 and December 2021. Medical records were reviewed and information concerning age, sex, vital signs, underlying diseases, clinical signs and symptoms, laboratory findings, radiologic findings, treatment, and clinical outcomes was collected. An odds ratio (OR) for the risk factors associated with pneumothorax was calculated using the binary logistic regression model.ResultsAmong 179 consecutive patients diagnosed with pulmonary paragonimiasis, the postive rate of pneumothorax was 10.6% (19/179). Pneumothorax occurred mostly in the right lung (78.9%, 15/19), and intrapulmonary parenchymal lesions showed an ipsilateral relationship with pneumothorax (94.7%, 18/19). Fifteen patients (78.9%, 15/19) of pneumothorax associated with pulmonary paragonimiasis are accompanied by pleural effusion. Most of patients with pneumothorax (89.5%, 17/19) underwent chest tube insertion as a first treatment. Three patients (15.8%) showed relapses but in no case was a death recorded. asthma (odds ratio [OR] 8.10, 95% confidence interval [CI] 1.43-45.91), chest pain (OR 8.15, 95% CI 2.70-24.58), and intrapulmonary lesions (OR 8.94, 95% CI 1.12-71.36) were independent risk factors for pulmonary paragonimiasis-associated pneumothorax.ConclusionsOur findings suggest that clinicians should keep in mind the possibility of pneumothorax when approached by patients with pulmonary paragonimiasis complaining of chest pain, accompanied by intrapulmonary lesions or with asthma as an underlying disease. Paragonimiasis, as a typical food-borne zoonotic helminthiasis, is an important public health problem. Approximately one million people suffer from paragonimiasis annually and areas in which the disease is newly endemic are increasingly identified. Paragonimiasis causes complex symptoms in multiple organs, but chest symptoms are its most distinguishing clinical feature. Most symptomatic paragonimiasis infections appear as pulmonary diseases such as pneumonia, bronchitis, pleuritis with pleural effusion, and pneumothorax. Pneumothorax is a debilitating and expensive symptomatic pulmonary complication that can occur in cases of paragonimiasis. Therefore, it is necessary to be aware of the risk factors for pneumothorax in patients with pulmonary paragonimiasis and to evaluate the possibility of pneumothorax in those patients. Our study suggests that history of asthma, chest pain, and intrapulmonary lesions are clinically significant risk factors of pneumothorax associated with pulmonary paragonimiasis. Clinicians should approach patients with pulmonary paragonimiasis that complain of chest pain or have intrapulmonary lesions or asthma as an underlying disease with the possibility of pneumothorax in mind and should note that pulmonary paragonimiasis is one of the causes of the differential diagnosis of secondary spontaneous pneumothorax.