3.1 Clinical characteristics
Totally, 2.5% (6/237) cases with cystic lesions were confirmed pathologically with PIE between January 2011 and April 2019 in the Department of pathology, West China Hospital of Sichuan University. And all the patients were treated with suggested therapy and then with surgery.
The clinical characteristics of all the six patients are showed inTable 1 . There were four girls and two boys, ranged from 2 months to 5 years old. We collected the follow-up data of all patients except for No.4. No.4 patient had the wrong phone number. The other available patients (5/5, 100%) were all full-term without mechanical ventilation. The common symptoms of the patients were cough, fever and expectoration. All patients with PPIE were presenting as lung cysts with primary syndrome of respiratory infection. The cystic lesion was located at a single lobe among 66.7% (4/6) patients, who were identified with local PPIE. 33.3% (2/6) patients affected both lung lobes, who were identified with diffuse PPIE.
Besides, patient No.5 has suffered the disease Langerhans cell histiocytosis (LCH) in the left submandibular lymph node for 1 year. She was asymptomatic when she has received the suggested chemotherapy treatment four times, she had suffered recurrent pneumonia for 3 months, and the routine examination of the chest CT found the diffuse cystic lesions in both lung lobes. In addition, she had the defect of ventricular septal defect.