2024年 · 第104卷第22期

The patient, a 28-year-old male, went to the Department of Respiratory and Critical Care Medicine of the First Affiliated Hospital of Zhengzhou University because of "interstitial changes in both lungs were found for 3 years, fever and dyspnea for 4 days". Physical examination 3 years ago revealed interstitial changes in both lungs, which were not treated. Fever appeared in 4 days, showing relaxed fever, accompanied by cough, expectoration, and progressive dyspnea. No previous history of chronic diseases such as hypertension or diabetes. Deny that the relative has a history of similar disease and familial genetic disease. After admission, chest CT examination showed diffuse lesions in both lungs, considering interstitial changes and infection in both lungs. After anti-infective treatment, body temperature returned to normal, cough and dyspnea gradually alleviated. One month later, reexamination of chest CT showed diffuse miliary nodules in both lungs, some of which were dense, with clear and sharp edges. Stripe and flake calcification shadows were seen in both lungs, mainly in both lower lungs, linear calcification shadows were seen in bilateral pleura, and narrow and long translucent bands were seen in the lateral chest wall and the outer edge of the lungs (Figures 1 and 2). Considering the possibility of pulmonary alveolar microlithiasis (PAM), whole exon sequencing of peripheral blood indicated heterozygous nonsense mutation and frameshift mutation of chromosome 4p15.2, mainly involving exons 8 and 13 of SLC34A2 gene, and confirmed the diagnosis of PAM. PAM is a rare autosomal recessive genetic disease, characterized by abnormal calcium deposition in some organs, especially in the lungs. Calcification can also be seen in some extrapulmonary organs such as kidney, gallbladder, ureter, seminal vesicles, pleura and heart in some patients with PAM. Lung transplantation is currently the only known effective treatment for PAM.