Congenital Pulmonary Alveolar Proteinosis

Pulmonary alveolar proteinosis (PAP) is a rare syndrome characterized by pulmonary surfactant accumulation within the alveolar spaces. It occurs with a reported prevalence of 0.1 per 100,000 individuals. Two clinically different pediatric types have been defined as congenital PAP which is fatal and a late-onset PAP which is similar to the adult form and less severe. The clinical course of PAP is variable, ranging from spontaneous remission to respiratory failure. Whole-lung lavage is the current standard treatment for PAP patients. We report a new congenital case of PAP. 1. Introduction Pulmonary alveolar proteinosis (PAP) is rare respiratory disease characterized by the accumulation of surfactant-derived material in the lungs [1, 2]. In pediatric practice, two forms are recognized: congenital alveolar proteinosis (CAP) and a later-onset form that is generally less severe. The main symptoms are nonspecific. Bronchoalveolar lavage is the key to diagnosis [3]. We present a new pediatric case of congenital alveolar proteinosis. 2. Case Report A 3-month-old boy was referred to our pediatrics department because of chronic tachypnea and weight loss. The patient was born at term in 2011, with no immediate postnatal respiratory distress. The parents were second-degree consanguineous. The infant presented with a 3-week history of dyspnea and oxygen dependence. The infant had a sister who had died at the age of 3 months from respiratory failure. Physical examination revealed that he weighed 4.5？kg and his height was 58？cm. His heart rate was 130 beats per minute and his respiratory rate was 60 breaths per minute. He had peripheral cyanosis and intercostal retractions. Fine inspiratory crackles could be heard throughout the chest on auscultation. His transcutaneous oxygen saturation while breathing room air was 80%. The minimum oxygen flow needed to have transcutaneous oxygen saturation greater than 92% was 8？L/mn. The liver and spleen were not enlarged. Laboratory tests showed low total protein 54？g/L and albumin 20？g/L, liver enzymes, renal function, and full blood count were normal. Inflammatory markers were slightly increased. Arterial blood gases on oxygen were 7.38, Pco2 4.81？KPa, and Po2 8.53？KPa. Chest X-ray revealed diffuse alveolar infiltration with an air bronchogram (Figure 1). Chest CT scan showed diffuse interstitial and alveolar infiltration (Figure 2). Echocardiography was normal. Respiratory fungal, viral, and bacterial pathogens were all negative. HIV testing was also negative. Because of a typical chest computed tomography and chest X-ray, and