Rapid development of metastatic pulmonary calcifications in primary hyperparathyroidism: a case report and literature review

Abstract

Background: Metastatic pulmonary calcification (MPC) is rarely reported in primary hyperparathyroidism, especially MPC develops quickly. We report such a case here with a literature review.

Case presentation: A 41-year-old woman presented with cough and dyspnea. Data from clinical, radiological, pathological, technetium (^99mTc)-methylene diphosphonate (MDP) bone scintillation imaging, and ^99mTc-methoxy isobutyl isonitrile (MIBI) thyroid imaging were studied. ^99mTc-MIBI thyroid imaging indicated hyperparathyroidism. Chest computed tomography (CT) scans showed rapidly progressive bilateral pulmonary multiple high-density shadows with mass consolidation and exudation in only five days. ^99mTc-MDP bone scintillation imaging indicated bilateral pulmonary calcifications. CT-guided lung biopsy showed multifocal irregularities of calcium deposition and calcified bodies in the pulmonary interstitium. The patient showed gradually clinical and radiological improvement after surgical removal of the parathyroid adenoma.

Conclusion: Rapidly progressive MPC tends to be misdiagnosed as many primary pulmonary diseases. ^99mTc-MDP bone scintillation imaging and pulmonary biopsy could be performed to differentiate metastatic pulmonary calcification from other diseases. Surgical resection of the parathyroid gland is helpful for treatment of MPC in patients with primary hyperparathyroidism and is regularly recommended.

Keywords: 99mTc-MDP bone scintillation imaging; 99mTc-MIBI thyroid imaging; Metastatic pulmonary calcification; Primary hyperparathyroidism.

Fig. 1

Representative ^99mTc-MIBI thyroid images indicative of hyperparathyroidism. The patient was intravenously injected with 740–925 MBq^99mTc-MIBI. A single-photon emission (SPECT)/CT instrument was used, which was equipped with a parallel low-energy high-resolution collimator with an energy peak of 140 keV and a window width of 20%. The magnification when performing the neck scan was 1.5-fold, with a matrix of 128 × 128 pixels and an acquisition count of 1000 K at 10 min and an acquisition count of 682 K at 120 min ^99mTc-MIBI injection. Two points have the same acquisition time of 600 s. Neck systemic planar images were obtained after 10 min a and 120 min b; c-e There is a soft tissue nodule located in the posterior lobe of the left thyroid gland, with radioactive accumulation

Fig. 2

CT scanning of the chest. a, b Initial CT scans: A little linear opacity on the bilateral pulmonary. c, d CT scans five days later: Bilateral pulmonary multiple high-density shadow with mass consolidation and exudation; obvious progression when compared with initial scan. e, f Chest image after treatment of two weeks: Obvious calcification in bilateral lungs. g, h Chest CT after left parathyroidectomy: Lesions were mildly improved. i, j Pulmonary calcifications did not deteriorate or improve 8 months later in the follow-up examination

Fig. 3

Representative hematoxylin and eosin (H&E) staining of tissue sections from CT-guided biopsy of left pulmonary a, b and left parathyroidectomy c, d. a The alveoli structure was partially damaged. Fibrosis and interalveolar septa broadening were seen in the pulmonary interstitium with multifocal calcium deposition and irregular-shaped calcified bodies. No obvious inflammatory cell or giant cell reaction was observed in pulmonary interstitium (H&E 100 × .). b Multifocal irregularities of calcium deposition and the calcified bodies in the pulmonary interstitium were seen at high magnification (white arrow), some of which resemble the psammoma bodies seen in a thyroid gland papillary carcinoma (red arrow) (H&E 200 × .). c Tumor cells were shown as the organ-like tissue structure and the tumor cells were in the nest-like distribution. Branched blood vessels were found between the cells and no tumor necrosis was observed (H&E 100 × .). d High magnification revealed the nest-like distribution of tumor cells, which were round or columnar with the cytoplasm being transparent and the nucleus being round or oval. Neither nucleus atypia nor mitotic activity was observed. Sinusoid segmentation could be found between the tumor cells (H&E 200 × .)

Fig. 4

Representative ^99mTc-MDP bone scintillation images showing pulmonary calcification. The patient was intravenously injected with 740–925 MBq ^99mTc MDP and emptied the bladder after 3 h. A SPECT instrument was used, which was equipped with a parallel low-energy high-resolution collimator. Anterior and posterior views were imaged at same time with scanning speeds of 15–20 cm/min and matrix 1024 × 256 pixels