PULMONARY ROCKS! A CASE OF PULMONARY ALVEOLAR MICROLITHIASIS

TOPIC: Diffuse Lung Disease TYPE: Fellow Case Reports INTRODUCTION: Pulmonary alveolar microlithiasis (PAM) is an extremely rare lung disease characterized by the development of calcium phosphate deposits (microliths) within spaces. Genetic mutations in SLC34A2 gene (solute carrier family 34 member 2 gene), which encodes for a sodium-phosphate co-transporter, have been described as cause disease. This co-transporter located on type II pneumocytes and responsible removing ions from space. Without effective transport, bind to leading alveoli. Over time this often leads pulmonary fibrosis progressive respiratory failure. Here, we present case that was initially suspected be metastatic endometrial carcinoma. CASE PRESENTATION: A 37-year-old female presented gynecology clinic evaluation abnormal uterine bleeding. Endometrial biopsy showed endometrioid adenocarcinoma uterus. Staging CT scans revealed bilateral adnexal masses, liver, peritoneal carcinomatosis, concern lymphangitic carcinomatosis lungs due calcification pleura diaphragm. Liver confirmed ovarian primary consistent with synchronous stage IV cancer. She underwent chemotherapy carboplatin paclitaxel well abdominal hysterectomy debulking surgery good response; however, repeat chest persistent innumerable calcified micronodules extensive pleural, fissural, interlobular calcifications. Transbronchial biopsies were obtained diffuse intra-alveolar laminated concentric microliths diagnostic microlithiasis. At diagnosis her function testing mild restriction. has no history had symptoms. Calcium supplements discontinued, she treated low phosphorus diet. continues undergo monitoring symptoms function. DISCUSSION: PAM genetic caused defective accumulation failure typical death, although rate progression variable. There known treatment except transplant. diet, bisphosphonates, repeated bronchoalveolar lavage studied without clear clinical benefit. CONCLUSIONS: (See Discussion) REFERENCE #1: Castellana G, Gentile M, R, Resta O. microlithiasis: review 1022 cases reported worldwide. Eur Respir Rev. 2015 Dec;24(138):607-20. #2: Saito A, McCormack FX. Alveolar Microlithiasis. Clin Chest Med. 2016;37(3):441-448. doi:10.1016/j.ccm.2016.04.007. DISCLOSURES: No relevant relationships Carlos Cardenas, source=Web Response Sakda Sathirareuangchai, Andrew Tomlinson,