Metastatic pulmonary calcification mimicking pulmonary tuberculosis: A case report

Area of Science:

• Pulmonology
• Nephrology
• Radiology

Background:

• Metastatic pulmonary calcification (MPC) involves calcium deposition in lung tissue due to hypercalcemia.
• Diagnosis often requires advanced imaging like CT, as chest X-rays lack sensitivity.
• Typical CT findings include centrilobular nodules, predominantly in upper lung lobes.

Observation:

• A 30-year-old woman with end-stage kidney disease initially diagnosed with pulmonary tuberculosis.
• Her computed tomography (CT) scan showed atypical tree-in-bud nodules, usually indicative of infection.
• Bronchoalveolar lavage was negative for Mycobacterium, and transbronchial lung biopsy confirmed interstitial calcium deposition.

Findings:

• The patient's presentation mimicked infection but was ultimately diagnosed as metastatic pulmonary calcification.
• Atypical CT findings complicated the initial diagnosis, underscoring the limitations of imaging alone.
• Histopathological examination of lung biopsy was crucial for definitive diagnosis.

Implications:

• This case underscores the importance of considering MPC in patients with hypercalcemia, particularly those with end-stage kidney disease.
• Atypical imaging findings necessitate a high index of suspicion and further diagnostic workup.
• Accurate diagnosis of MPC is vital for appropriate management and to avoid unnecessary treatments for misdiagnosed conditions.