P1-66: Metastatic pulmonary calcification mimicking miliary pulmonary tuberculosis: A case report

Page Source : https://onlinelibrary.wiley.com/doi/10.1111/resp.14150_66

Thian Chee Loh, Yong Kek Pang, Chong Kin Liam, Man Fong Chew, Jiunn Liang Tan, Chee Kuan Wong, Mau Ern Poh, Ka Kiat Chin, Vijayan Munusamy, Nur Husna Ibrahim

Department of Medicine, Faculty of Medicine, University of Malaya, Malaysia, Department of Pathology, Faculty of Medicine, University of Malaya, Malaysia

Metastatic pulmonary calcification (MPC) is a metabolic lung disease characterised by deposition of calcium in the normal lung parenchyma secondary to chronic elevation of serum calcium. In radiological imaging, one of the common changes is multiple diffuse small nodules. We report a case of a 30 – year – old woman with end stage renal disease, who was initially diagnosed as pulmonary tuberculosis and then was revised to have MPC. The patient was admitted to the hospital for calcific uraemic arteriolopathy when she presented with discolouration and pain of her left lower limb. Blood investigation revealed serum calcium of 2.74 mmol/L and iPTH of 151 pmol/L. Chest radiograph taken during admission showed diffuse tiny nodules in bilateral lung fields suggestive of miliary changes. We proceeded with a CT thorax which showed tiny centrilobular nodules of <3 mm scattered over bilateral lung fields in which some were calcified. She was otherwise asymptomatic of pulmonary tuberculosis. There were no other causes of hypercalcaemia identified. Bronchioalveolar lavage was direct smear – negative for acid fast bacilli and culture – negative for Mycobacterium tuberculosis. Transbronchial lung biopsy showed deposits in the interstitium which were positive for Von Kossa stain, consistent with calcification.