Alveolar Proteinosis With Profound Hypoxemia at Presentation.

SESSION TITLE: Interstitial Lung Disease Cases IISESSION TYPE: Affiliate Case Report SlidePRESENTED ON: Wednesday, October 29, 2014 at 11:00 AM - 12:15 PMINTRODUCTION: Pulmonary alveolar proteinosis (PAP) is an uncommon disease characterized by varying degrees of dyspnea and hypoxemia. Reports of PAP progressing to respiratory failure requiring mechanical ventilation are rare.

CASE PRESENTATION: A previously healthy 31 year old male presented with four months of progressive dyspnea. At presentation he was profoundly hypoxemic, with a PaO2 of 64 mmHg while receiving 20 liters supplemental oxygen. A chest radiograph revealed bilateral groundglass opacities. Subsequent chest CT demonstrated diffuse airspace disease with a crazy paving pattern sparing only the extreme apices and bases. Serological workup for infectious and autoimmune etiologies was negative. He was intubated prior to bronchoscopy; bronchoalveolar lavage fluid stained positive for PAS (periodic acid-Schiff) supporting the diagnosis of PAP. His hypoxia progressed after intubation requiring 100% FiO2, high positive end expiratory pressure, and inhaled nitric oxide. Due to his hypoxemia, there was concern he would not tolerate the single lung ventilation necessary for whole lung lavage (WLL), therefore he underwent cannulation and initiation of venovenous extracorporeal membrane oxygenation (ECMO). Immediately after ECMO commenced, WLL of both of both lungs was completed in a single session using a total of 30 liters for each lung with progressive clearing of the lavage return throughout the procedure. His condition improved and he was discharged home five days later without supplemental oxygen.

DISCUSSION: This case is a uniquely severe presentation of PAP causing hypoxemic respiratory failure requiring mechanical ventilation. WLL is the mainstay of treatment for PAP, but requires the ability to tolerate single lung ventilation and is typically performed in two individual sessions separated by days to weeks. In our patient, the severity of hypoxemia precluded the use of single lung ventilation and necessitated urgent bilateral WLL. ECMO support to allow WLL in severe PAP was first described in CHEST in 2001.1CONCLUSIONS: While WLL is the established primary treatment for PAP, the procedure may not be tolerated in the rare patient who presents with respiratory failure secondary to the disease. Our case demonstrates the role of ECMO during bilateral WLL. Reference #1: Cohen, ES et al. Pulmonary alveolar proteinosis causing severe hypoxemic respiratory failure treated with sequential whole-lung lavage utilizing venovenous extracorporeal membrane oxygenation: a case report and review. CHEST 2001; 120, 1024-1026DISCLOSURE: The following authors have nothing to disclose: Kristyn Sayball, Thomas Iden, Ray Shepherd, Ehab HusseinNo Product/Research Disclosure Information.