2024年 · 第47卷第02期

In this issue, the "Diagnosis and Treatment Plan" column published the "Technical Specification for Bronchial Challenge Test of Methacholine (Methacholine Chloroacetate) (2023 Edition)". This consensus was composed by experts from the Lung Function and Clinical Respiratory Physiology Working Committee of Respiratory Physicians Branch of Chinese Medical Doctors Association, the Lung Function Group of Respiratory Disease Branch of Chinese Medical Association (in preparation) and the Lung Function Group of Respiratory Branch of Chinese Geriatric Association. Based on the "Lung Function Guidelines-Bronchial Challenge Test Examination" released in 2014 and its problems in use and recent research progress, 11 core issues in the clinical practice of methacholine bronchial challenge test (MCT) in China were collected and recommended, including the indications and contraindications of MCT, the preparation of challenge reagents, the test process and methods, quality control, safety management, result interpretation and reporting specifications, etc., which deserve attention.

Case 1: A 29-year-old female was admitted to the hospital on 21 December 2020 due to "cough and sputum for half a year". In the past six months, the patient had a cough without obvious trigger, which was paroxysmal and irritating. It was at night, accompanied by expectoration, which was yellow phlegm. The daily amount was about 15 ml. There was no fever, night sweats, chest pain, hemoptysis, chest tightness, holding breath and other discomfort. He took "cefixime" for treatment, but the symptoms did not improve. On December 17, 2020, the chest CT of the local hospital showed right pneumonia with local abscess formation, scoliosis, and sternum depression. Previous denial of tuberculosis, liver disease, hypertension, diabetes history, no tobacco and alcohol addiction. Personal history and family history are not special. Physical examination: The superficial lymph nodes of the whole body were not palpable, the breathing sounds of both lungs were coarse, no dry and wet rales were heard, the heart rate was 85 beats/min, the rhythm was uniform, no pathological murmur was heard in the auscultation area of each valve, the abdomen was flat and soft, the liver and spleen were not palpable under the costs, and no edema in both lower limbs. Laboratory test: blood routine: white blood cells 8.4×10⁹/L, neutrophils 0.83. The results of four items of coagulation + D-dimer, arterial blood gas analysis, G test, GM test, T-SPOT, antinuclear antibody, ENA zymogram, PPD test, sputum fungal smear, sputum acid-fast bacillus smear, sputum culture and drug susceptibility test were all negative. Pulmonary tumor markers, urine and stool routine were all in the normal range. Auxiliary examination: normal pulmonary function. Enhanced CT of the chest showed a funnel-shaped depression from the lower edge of the sternal angle to the xiphoid process; A honeycomb shadow with increased density was seen in the lower lobe of the right lung, with clear boundaries and cavities inside. Enhanced scan showed that multiple blood supply arteries came from the thoracic aorta, and the drainage vein was the pulmonary vein in the lower lobe of the right lung (Figures 1~4). CT diagnoses were right lower pulmonary intra-lobar pulmonary sequestration (cavitation type), pectus excavatum, and scoliosis. Therapeutically, piperacillin and tazobactam (3.375 g, once/8 h, intravenous drip) were given to fight the infection. After 1 week of treatment, the symptoms improved and the patient was discharged from the hospital. The patient refused surgical treatment. During regular review, the most recent review date was August 1, 2023, and only plain chest CT scan was reviewed.

Background: autoimmune pulmonary alveolar proteinosis (aPAP) is the most common PAP, which is caused by the defect of surfactant clearance by alveolar macrophages mediated by anti-granulocyte macrophage colony-stimulating factor (GM-CSF) antibodies; At the same time, it will also affect the function of alveolar macrophages and centrophils in aPAP patients, which is easy to complicate infectious diseases. About 5% to 13% of patients with PAP may have secondary infection, but no bulk cases of concurrent infection in aPAP patients have been reported. Objective: To describe the clinical characteristics and outcome of aPAP cases and to explore the risk factors of opportunistic infection in aPAP patients. METHODS: This retrospective study included aPAP patients from 2008 to 2018 in France and Belgium, and the following data were collected through a standardized questionnaire: demographic data, comorbidities, imaging characteristics, clinical outcome, pathogenic microorganism data. Results: A total of 104 patients with aPAP were included, with a median age of 45 years; Male accounts for 2/3. The median follow-up time was 3.4 years (quartile 1.7 to 6.6 years), and 60 patients (58%) developed at least one infection, of which 23 (22%) were opportunistic: Nocardia infection was the most common (10). Thirty-five (34%) patients required hospitalization due to concurrent infections. Univariate analysis found that men were a risk factor for opportunistic infections (P=0.04，OR=3.88； 95%CI：1.02~22.06）。 The titers of GM-CSF antibodies were significantly increased in Nocardia-infected patients [1 058 (316-1 591)vs.580（200~1 190），P=0.01］。 Twenty-nine patients/28% healed themselves, and 70 patients received targeted therapy: 55 patients (79%) received whole lung lavage, 26 patients (37%) received subcutaneous GM-CSF, and 21 patients (30%) received rituximab. Eighty-one (78%) patients had a good prognosis, of which 30 were cured; Nine cases (9%) died, including 3 cases with malignant tumor, 2 cases with unknown cause of death, Pseudomonas aeruginosa pneumonia, aPAP progression, and 1 case each with chronic thromboembolic pulmonary hypertension or chronic obstructive pulmonary disease. Conclusion: aPAP patients are prone to opportunistic infections (especially Nocardia), but it does not affect their survival; It is recommended that bronchoalveolar lavage fluid or whole lung lavage fluid specimens from patients with aPAP be routinely screened for slow-growing pathogens to improve the diagnostic rate of these infections.