What is this summary about? This is a plain language summary of a late-stage clinical trial called IMPALA, originally reported in The New England Journal of Medicine. The IMPALA trial studied a drug called molgramostim nebulizer solution (molgramostim) to see how well it worked and how safe it was in patients with autoimmune pulmonary alveolar proteinosis (aPAP). Normally, tiny air sacs (alveoli) in the lungs are covered by a thin layer of an oily substance called surfactant that helps to keep them open. In aPAP, surfactant builds up and clogs alveoli making it difficult to breathe. Inhaled molgramostim helps to reduce the amount of surfactant clogging the alveoli.What were the results of the trial? After 24 weeks of treatment, patients who received molgramostim every day had better oxygen transfer into blood than patients who received an inactive substance (placebo). Patients’ sense of well-being and quality of life was improved more with daily molgramostim than placebo. The amount of surfactant in the lungs measured using scans and the number of whole-lung lavages (lung washes) patients required were lower with daily molgramostim than placebo. The number of medical problems (adverse events) was similar in patients who received molgramostim and placebo except for chest pain, which was more common with molgramostim.What do the results of the trial mean? The IMPALA trial demonstrated that molgramostim is a promising treatment option for people with aPAP.

Pulmonary alveolar proteinosis (PAP) is an ultra-rare disease caused by impaired pulmonary surfactant clearance due to the dysfunction of alveolar macrophages or their signaling pathways. PAP is categorized into autoimmune, congenital, and secondary PAP, with autoimmune PAP being the most prevalent. This article aims to present a comprehensive review of PAP classification, pathogenesis, clinical presentation, diagnostics, and treatment. The literature search was conducted using the PubMed database and a total of 67 articles were selected. The PAP diagnosis is usually based on clinical symptoms, radiological imaging, and bronchoalveolar lavage, with additional GM-CSF antibody tests. The gold standard for PAP treatment is whole-lung lavage. This review presents a summary of the most recent findings concerning pulmonary alveolar proteinosis, pointing out specific features that require further investigation.

UNASSIGNED: We report a life-threatening case of severe respiratory failure due to a pulmonary alveolar proteinosis (PAP) secondary to lysinuric protein intolerance (LPI), complicated by a pre-existing right pneumothorax, which we treated using a rescue whole-lung lavage (WLL). To date, in the literature, there are no cases of WLL performed in this condition.
UNASSIGNED: Patient was referred to our center because of rapidly worsening dyspnea and deterioration of gas exchange, caused by a secondary form of PAP which required an immediate therapeutic option such as the one offered by WLL. On physical examination, bilateral crackles were present, and peripheral blood oxygen saturation was 78% on oxygen with a FiO2 of 40%.
UNASSIGNED: After stabilizing the clinical conditions with oxygen therapy erogated through a high-flow nasal cannula, shortly after admission, we performed a rescue WLL among two procedures. The procedure was very effective, and the patient was later discharged without oxygen therapy and in good clinical condition.
UNASSIGNED: Our case report represents a chance to help fill the gap of knowledge relative to secondary forms of PAP. The patient we presented suffers from a very rare genetic condition (LPI) that only has a few reported cases in the literature and has a very low prevalence which makes it difficult to produce the affected people:newborns ratio. We believe that difficult and rare cases like this one can improve our understanding of the disease and, most importantly, of how much the only therapeutic option we had, a rescue WLL, is effective to improve gas exchange and radiological features, despite being performed in these severe respiratory conditions.

Whole lung lavage (WLL) has been recognized as the most effective therapy of severe pulmonary alveolar proteinosis (PAP). Most centers perform the lavage of each lung in two sessions under general anesthesia at an interval of several days to weeks. Compared with two-session WLL, one-session bilateral sequential WLL only requires general anesthesia once. However, the safety of one-session WLL in PAP patients has not been assessed by large cohort studies. In this study, we aimed to investigate the association between the mode of WLL procedure (one-session or two-session) and the risk of periprocedural complications in PAP patients.
In this single-center retrospective cohort study, we included adult patients who were diagnosed as PAP and had undergone WLL procedures under general anesthesia from 2000 to 2022. Patients requiring extra-corporeal oxygenation during WLL were excluded. Since some patients received multiple WLL procedures, we considered each procedure in one-session or two-session group as a unique unit in our analysis. The primary outcome was the occurrence of any complications during hospitalization, including termination of WLL procedure due to fluid leakage or refractory hypoxemia, bronchospasm, delayed endotracheal extubation, cardiovascular event, pneumothorax, and fever.
We included a total of 175 WLL procedures (118 patients), with 48 in the two-session group and 127 in the one-session group. Periprocedural complications occurred in 17 (35.4%) and 39 (30.7%) procedures in the two-session and the one-session groups, respectively. The risk of periprocedural complications did not differ significantly between groups, after adjusting the unbalanced confounders in a multivariable model (odds ratio 0.95, 95% confidence interval 0.34 to 2.69, P 0.929) or by inverse probability of treatment weighting (odds ratio 0.70, 95% confidence interval 0.30 to 1.54, P 0.379). Compared with the two-session WLL group, the one-session WLL group had a shorter postprocedural length of hospitalization and comparable decrease in alveolar-arterial oxygen tension gradient from baseline.
One-session bilateral WLL was not associated with an increased risk of periprocedural complications compared with two-session WLL in PAP patients. Experienced physicians may consider performing one-session WLL in view of the comparable safety and efficacy and potential advantages of saving time.

A 61-year-old patient with cystic bronchiectasis and bronchial artery hyperplasia in the left lung was diagnosed with polymyositis-related interstitial lung disease. After nine months of immunosuppressive therapy, he developed unilateral autoimmune pulmonary alveolar proteinosis (APAP) in the right lung with respiratory failure. After bronchial artery embolization to prevent massive hemoptysis, whole-lung lavage was performed using veno-venous extracorporeal membrane oxygenation. His respiratory condition improved, and he was discharged from the hospital with supplemental oxygen. Three reported cases of APAP with polymyositis-related interstitial lung disease, including the present case, were all positive for anti-glycyl tRNA synthetase antibody and were under immunosuppressive treatment.

Pulmonary alveolar proteinosis is an uncommon cause of insidious onset shortness of breath and hypoxemia. It is caused by an accumulation of surfactant within the alveoli. Left untreated, it can be fatal. Standard-of-care treatment is whole-lung lavage; however, in severe cases, the associated hypoxemia can be profound and single-lung ventilation would not be tolerated, potentially preventing a lifesaving treatment. Single cases using veno-venous extracorporeal membrane oxygenation to perform whole-lung lavage have been reported. Here we describe three patients with severe pulmonary alveolar proteinosis who were successfully treated with whole-lung lavage using veno-venous extracorporeal membrane oxygenation for oxygenation support.

OBJECTIVE: Practice patterns for the use of extracorporeal membrane oxygenation (ECMO) during high-risk airway interventions vary, and data are limited. We aim to characterize our recent experience using ECMO for procedural support during whole-lung lavage (WLL) and high-risk bronchoscopy for central airway obstruction (CAO).
METHODS: We performed a retrospective cohort study of adults who received ECMO during WLL and high-risk bronchoscopy from 1 July 2018 to 30 March 2020. Our primary end point was successful completion of the intervention. Secondary end points included ECMO-associated complications and hospital survival.
RESULTS: Eight patients received venovenous ECMO for respiratory support during 9 interventions; 3 WLLs for pulmonary alveolar proteinosis were performed in 2 patients, and 6 patients underwent 6 bronchoscopic interventions for CAO. We initiated ECMO prior to the intervention in 8 cases and during the intervention in 1 case for respiratory decompensation. All 9 interventions were successfully completed. Median ECMO duration was 17.8 h (interquartile range, 15.9-26.6) for the pulmonary alveolar proteinosis group and 1.9 h (interquartile range, 1.4-8.1) for the CAO group. There was 1 cannula-associated deep vein thrombosis; there were no other ECMO complications. Seven patients (87.5%) and 4 (50.0%) patients survived to discharge and 1 year postintervention, respectively.
CONCLUSIONS: Use of venovenous ECMO to facilitate high-risk airway interventions is safe and feasible. Planned preprocedural ECMO initiation may prevent avoidable respiratory emergencies and extend therapeutic airway interventions to patients otherwise considered too high risk to treat. Guidelines are needed to inform the utilization of ECMO during high-risk bronchoscopy and other airway interventions.

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is a pulmonary syndrome wherein large volumes of phospholipid and protein-rich surfactants accumulate within the alveoli. PAP forms include primary (auto-immune PAP), secondary, and congenital. Nocardiosis is a form of suppurative disease induced upon infection with bacteria of the Nocardia genus. Clinically, cases of PAP complicated with Nocardia infections are rare, regardless of form. Unfortunately, as such, they are easily overlooked or misdiagnosed. We describe, here, the case of a patient suffering from simultaneous primary PAP and nocardiosis.
METHODS: A 45-year-old Chinese man, without history of relevant disease, was admitted to our hospital on August 8, 2018 to address complaints of activity-related respiratory exertion and cough lasting over 6 mo. Lung computed tomography (CT) revealed diffuse bilateral lung infiltration with local consolidation in the middle right lung lobe. Subsequent transbronchial lung biopsy and CT-guided lung biopsy led to a diagnosis of primary PAP (granulocyte-macrophage colony-stimulating factor antibody-positive) complicated with nocardiosis (periodic acid-Schiff-positive). After a 6 mo course of anti-infective treatment (sul-famethoxazole), the lesion was completely absorbed, such that only fibrous foci remained, and the patient exhibited significant symptom improvement. Follow-up also showed improvement in pulmonary function and the CT imaging findings of PAP. No whole-lung lavage has been conducted to date. This case highlights that active anti-nocardia treatment may effectively improve the symptoms and alleviate PAP in patients with PAP and nocardia, possibly reducing the need for whole-lung lavage.
CONCLUSIONS: When evaluating patients presenting with PAP and pulmonary infections, the potential for nocardiosis should be considered.

Pulmonary alveolar proteinosis is a rare disease characterized by progressive accumulation of lipoprotein material in the alveoli as a result of a dysfunction in surfactant clearance. The whole-lung lavage procedure is considered the current standard of care and consists of the sequential lavage of both lungs for mechanical removal of residual material in the alveoli. However, a lack of standardization has resulted in different procedural techniques among institutions. Even though whole-lung lavage is considered to be a safe procedure, unforeseen complications might occur, and proper knowledge of physiologic implications may allow clinicians to establish the appropriate therapy. This review provides an insight into the underlying physiology of the disease, the technical details of the procedure from an anesthesiologist\'s perspective, and discussion of potential intraoperative complications.

Autoimmune pulmonary alveolar proteinosis (PAP) is a rare lung disease. Although recombinant human granulocyte macrophage colony-stimulating factor (GM-CSF) therapy has emerged as a new therapeutic modality, whole-lung lavage (WLL) with manual chest percussion has been a standard therapy in advanced cases. The application of biphasic cuirass ventilation (BCV) instead of chest percussion has rarely been reported. We describe the case of a patient with advanced PAP who recovered well in both lungs, without complication, after we performed WLL with BCV under anesthetic mechanical ventilation. Both radiographical chest findings and clinical symptoms were improved, and oxygen therapy was finally withdrawn. This case illustrates that BCV can enhance the effective removal of lavage fluid and is an alternative to manual percussion.