Pulmonary alveolar proteinosis: A single center retrospective analysis of 14 cases

Selective bronchial occlusion for the prevention of pneumothorax after transbronchial lung cryobiopsy in a pulmonary alveolar proteinosis patient: a case report

The diagnosis of pulmonary alveolar proteinosis (PAP) is based on biopsies. Compared with other methods of taking biopsies, transbronchial lung cryobiopsy (TBLC) has a higher diagnostic rate and the likelihood of pneumothorax. Selective bronchial occlusion (SBO) is an effective technique for treating intractable pneumothorax. However, there are no data available about SBO for the prevention of pneumothorax after TBLC in a PAP patient. A 49-year-old man complained of recurrent cough and tachypnea, and his symptoms did not fully resolve until the diagnosis was confirmed, and he was treated with whole lung lavage. Our patient was ultimately diagnosed with PAP by TBLC but not multiple tests for the bronchoalveolar lavage fluid (BALF). The patient was discharged quickly after whole lung lavage due to the fact that he did not develop pneumothorax under SBO. This case illustrates that TBLC is a supplementary examination for PAP, especially for those in whom BALF results fail to confirm a diagnosis. Moreover, our report highlights that SBO is necessary to effectively prevent pneumothorax during and after multiple TBLCs in PAP patients.

CYFRA21-1 is a more sensitive biomarker to assess the severity of pulmonary alveolar proteinosis

Background

Serum lactate dehydrogenase (LDH), carcinoembryonic antigen (CEA) and CYFRA21-1 are the commonly used biomarkers to identify patients with autoimmune pulmonary alveolar proteinosis (APAP). However, it is not clear which of the biomarkers is more sensitive to the severity of the patient’s condition.

Methods

APAP patients numbering 151 were enrolled in this study. All patients’ severity was assessed through the severity and prognosis score of PAP (SPSP). According to the respective laboratory upper limits of serum levels of LDH, CEA and CYFRA21-1, APAP patients were divided into higher and lower-level groups. Patients were divided into five groups based on SPSP. 88 patients had completed six months of follow-up. We calculated sensitivity, specificity, and critical point of LDH, CEA and CYFRA21-1 between APAP patients and normal control group, and between grade 1–2 and 3–5 through receiving operating characteristics (ROC) curve.

Results

Serum LDH, CEA and CYFRA21-1 levels of patients with PAP were higher and distinctly related to PaO₂, FVC, FEV₁, DLCO, HRCT scores and SPSP. The SPSP of patients in higher-level LDH, CEA and CYFRA21-1 groups were higher than those of corresponding lower-level groups. Based on SPSP results, the patients were divided into five groups (grade I, 20; grade II, 37; grade III, 40; grade IV, 38; grade V, 16). The serum level of CYFRA21-1 of patients with APAP in grade II was higher than that of patients in grade I and lower than that of patients in grade III. Serum CYFRA21-1 of patients with APAP after six months were higher than the baseline among the aggravated group. Serum LDH, CEA and CYFRA21-1 levels after six months among patients in the relieved group of patients with APAP were lower than the baseline. ROC correlating LDH, CEA and CYFRA21-1 values with APAP severity (between grade 1–2 and 3–5) showed an optimal cutoff of LDH of over 203 U/L (< 246 U/L), CEA of over 2.56 ug/L (< 10 ug/L), and CYFRA21-1 of over 5.57 ng/ml (> 3.3 ng/ml) (AUC: 0.815, 95% CI [0.748–0.882], sensitivity: 0.606, specificity: 0.877).

Conclusion

Serum CYFRA21-1 level was more sensitive in revealing the severity of APAP than LDH and CEA levels among mild to moderate forms of disease.