대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Acute Mercury Vapor Inhalation

Radiologic Findings

Figs 1. Chest PA showsperipheral consolidation in left upper to mid lung zones and several bullae in both upper lung zones. Fig 2-4. CT scans after 2 days showed increased extent of diffuse GGOs with upper lung zone predominance and underlying emphysema or bullae in both lungs. Fig 5-7. Follow up CT scans after 7 days showed interval decreased diffuse GGOs but rapid progression of asymmetric fibrosis showing reticular opacities and bronchiectasis in both lungs.

He has a history of mercury vapor inhalation at the home one day before ER admission. He burned 40 sheets of amulets in the confined space and the mercury is one of the ingredient of ink which is use for the letter of amulets. The serum mercury level was 54.6 microgram/L and his symptom had relieved after using steroid and radiologic abnormalities were reversible and resolved during the follow up.

Brief Review

Mostly mercury poisoning occurs in workers exposed to mercury vapors over a long perioid of time: fur or felt hat-making, dental profession, extract gold from mercury amalgam or accidents within the home and the symptom includes gingivitis, stomatitis, fine tremor and irritability. However, rarely acute mercury poisoning could happen and lung appears to be primarily affected in the case of acute exposure to metallic mercury vapor causing chemical pneumonitis.
The major radiographic abnormalities are diffuse bilateral interstitial infiltrates or consolidation. The early CT findings are ground glass opacity, alveolar consolidation and ill definedcentrilobular nodules. In mild cases, scattered, ill defined nodular opacities are dominant. In more severe cases, patchy areas of ground glass opacity and consolidation, predominantly in the subpleural region and in the upper to mild lung zones, are seen. In the most severely affected cases, all lung zones are involved.
Postmortem studies have shown severe damage to the bronchi and bronchioles with marked alveolar edema. In the presence of marked necrosis, complications such as interstitial emphysema, pneumomediastinum and pneumothorax can occur.
Most of the interstitial changes are inflammatory edema and are reversible, especially when exposure is relatively mild. But mercury apparently persists in lung tissue for several months which could be significantly related to the interstitial fibrosis.

References

1. Hashimoto M, Sato K, Heianna J et al. Pulmonary CT Findings in Acute Mercury Vapour Exposure. ClinRadiol 2001;56:17-21.
2. Asano S, Eto K, Kurisaki E et al. Acute inorganic mercury vapor inhalation poisoning. Pathology International 2000;50:169-174.
3. Lim H.E, Shim J.J, Lee S.Y. et al. Mercury inhalation poisoning and acute lung injury. Korean J Intern Med 1998;13(2):127-130.

Keywords

Lung, inhalational lung injury, Inhalation and aspiration disease,