Secondary pulmonary alveolar proteinosis: a single-center retrospective study (a case series and literature review)

Abstract

BackgroundSecondary pulmonary alveolar proteinosis (sPAP) is an extremely rare disease. The clinical features of sPAP patients remain to be summarizeds. MethodsPatients pathologically diagnosed with PAP and with negative results for anti-granulocyte macrophage colony stimulating factor (GM-CSF) autoantibodies from Peking Union Medical College Hospital between January 2000 and July 2016 were retrospectively studied. The PubMed database was also searched for literature to collect published cases.ResultsIn our center, nine patients were diagnosed as sPAP with a median age of 37 years. Hematological disorders, including myelodysplastic syndrome (MDS), chronic myelogenous leukemia (CML), and pulmonary tuberculosis (TB) infection were the underlying diseases. Cases secondary to MDS had very poor prognosis as all of them survived less than 2 years after their diagnosis, while those secondary to TB had favorable prognosis. Only 33.3% of cases showed interlobular septal thickening in our sPAP group. Through literature review, 164 sPAP cases were collected. The age at diagnosis was 45.0 ± 14.8 years old and the gender radio was 1.20:1 (M:F). 61.9% of cases were diagnosed by bronchoscopy. MDS and CML were common underlying diseases in 34.1% and 15.2% of patients, respectively. Patients with sPAP secondary to hematological diseases had a short survival time and half of them died within 14.95 months after diagnosis.ConclusionsMDS and TB infection were the most frequent underlying causes of sPAP in this single-center research in China, with cases secondary to MDS having a poor survival rate. sPAP was more likely to be secondary to hematological disorders, especially MDS and CML and had a fairly poor prognosis in published cases. sPAP should be suspected in PAP patients whose CT scan presents only ground-glass opacities without interlobular septal thickening.Electronic supplementary materialThe online version of this article (10.1186/s12890-018-0590-z) contains supplementary material, which is available to authorized users.

Pulmonary alveolar proteinosis in Korea: analysis of prevalence and incidence via a nationwide population-based study

“…In our PAP patients, mycobacterial infection was accompanied by about 5%. Several studies reported the association between tuberculosis (TB) and PAP [26][27][28][29]. Zhang et al reported that TB infection was identified in 44% of secondary PAP patients (n = 9) [26].…”

“…Several studies reported the association between tuberculosis (TB) and PAP [26][27][28][29]. Zhang et al reported that TB infection was identified in 44% of secondary PAP patients (n = 9) [26]. Some coexisting cases of PAP and TB have also been reported [27][28][29].…”

Pulmonary Alveolar Proteinosis Syndrome

“…Myelodysplastic syndromes and chronic myeloid leukemia are the most commonly reported hematological disorders associated with PAP syndrome. 2,[45][46][47][48][49][50][51][52][53][54] Although the pathogenic mechanisms underlying secondary PAP are not well understood, it is apparent that most predisposing conditions associated with secondary PAP result in reduced macrophage numbers or function, hence it is likely that the ability of alveolar macrophages to clear surfactant is compromised.…”

Pulmonary Alveolar Proteinosis Due to Pneumocystis carinii in Type 1 Hyper-IgM Syndrome: A Case Report

“…Pulmonary alveolar proteinosis (PAP), first described by Rosen et al (1) in 1958, is a rare diffuse lung disease of idiopathic etiology. Its estimated prevalence is about one in 3.7-6.9 × 10 6 with a male/female ratio of 1:1 to 2:1 (2)(3)(4)(5). Most patients are diagnosed between 20 and 50 years of age (2,(4)(5)(6).…”

“…Its estimated prevalence is about one in 3.7-6.9 × 10 6 with a male/female ratio of 1:1 to 2:1 (2)(3)(4)(5). Most patients are diagnosed between 20 and 50 years of age (2,(4)(5)(6). PAP is pathologically characterized by the presence of massive, amorphous, insoluble phospholipid-rich protein deposition in the alveolar and bronchial cavities.…”