Long-term follow-up after acute mercury poisoning-induced pneumonitis following cinnabar heating: A rare case report.

RATIONALE

Among 3 forms of mercury, elemental mercury vapor presents the highest threat due to its potential to cause acute pneumonitis. The management of acute mercury vapor poisoning remains unclear, particularly in acute lung injury. We present a case of mercury vapor poisoning resulting from the heating of cinnabar, successfully treated with high-dose corticosteroids and chelation therapy, and follow-up over 6 months.

PATIENT CONCERNS

A 47-year-old female patient was admitted to the Emergency Department due to dyspnea, chest tightness, and weakness following cinnabar heating.

DIAGNOSES

Upon admission, she presented with tachypnea and respiratory failure. During the first 5 days, the respiratory failure rapidly progressed, requiring high-flow nasal cannula support, and showed no improvement with broad-spectrum intravenous (IV) antibiotics and 80 mg daily IV methylprednisolone. Total blood and urinary mercury levels were measured to confirm the diagnosis.

INTERVENTIONS

Upon confirmation of acute pneumonitis due to mercury vapor poisoning, the patient was administered high-dose methylprednisolone (500 mg IV per day) and chelation therapy, which led to subsequent improvement.

OUTCOMES

Six months after discharge, the patient completely recovered, as evidenced by chest imaging and pulmonary function tests.

LESSONS

Heating elemental mercury can cause pneumonitis, leading to acute respiratory failure. A detailed history is crucial for diagnosis. High-dose methylprednisolone should be considered in patients who do not respond to lower doses. Patients should be monitored afterward to detect residual pulmonary fibrotic changes.