SESSION TYPE: ILD Student/Resident Case Report Posters
PRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM
INTRODUCTION: Pulmonary Alveolar Microlithiasis (PAM) is a rare disease characterized by microliths throughout the alveolar space, which are composed of calcium phosphate.
CASE PRESENTATION: A 29-year-old Honduras male presented with complaints of severe dyspnea, burning pleuritic chest pain (7/10), and palpitations that began the previous morning. These symptoms were intermittent and worsened over 24 hours. His chest pain resolved shortly after presentation to the hospital. He denied sputum production, fever, cough, and chills; and he had no other accompanying symptoms. The patient was generally healthy and had no significant past medical history or family history. The patient did not have any allergies and did not take any medications. He immigrated to the United States from Honduras at the age of 25 and worked as a painter. The patient was in no acute distress. Vital signs: Temperature 99.7 Deg.F, heart rate 110bpm, blood pressure 128/96mmhg, respiratory rate 15/min, oxygen saturation 96% on room air. Physical exam was only significant for bilateral crackles on lung auscultation. The remainder of the physical exam was markedly normal. Laboratory data was significant for normal-high hemoglobin and hematocrit, 15.9 gm/dl and 45.4%, respectively. Chest x-ray showed so-called “Sand Storm Appearance.” Chest CT scan demonstrated pleural densities suggesting calcification and scattered interstitial prominence (Fig. 1). Pulmonary function tests demonstrated restrictive ventilatory defects. The patient subsequently underwent video assisted thoracic surgery with biopsy. The pathologic diagnosis was PAM (Fig. 2).
DISCUSSION: PAM is a rare disease, which can be either sporadic or inherited. Puhr first described it in 1933 with over 500 cases reported worldwide to date (3). Typical presentations are similar to the above findings of “sandstorm” lungs and diffuse reticulonodular appearance (1). Most patients are asymptomatic despite striking radiographic findings with symptoms beginning around the third/fourth decades of life. Recent reports describe the role of mutation in Type IIB Sodium-Phosphate co-transporter gene (SCL34A2) in disease pathogenesis (2). Usually no treatment is required for the asymptomatic patients but in advanced cases lung transplantation and disodium etidronate have been tried with varied results.
CONCLUSIONS: PAM is a rare disease with characteristic radiographic picture that needs to be considered in differential diagnosis of interstitial lung disease.
1) Fuhrman, Carl R., Siddiqui, Nasir, A. Pulmonary Alveolar Microlithiasis. RadioGraphics 2011. 31:585-590.
2) Huquin, Izumi S., et. al. Mutations in the SLC34A2 gene are associated with pulmonary alveolar microlithiasis. Amer. Journal Resp. Crit. Care Medicine. 2007 Feb 1;175(3):263-8.
3) Puhr L. Microlithiasis alveolaris pulmonum. Virchows Arch Pathol Anat Physiol Klin Med 1933;290:156-160.
DISCLOSURE: The following authors have nothing to disclose: Brent Acker, Igor Aksenov
No Product/Research Disclosure InformationMemorial University Medical Center, Savannah, GA