A Case Report of Agriculture Occupational Pneumoconiosis in Maha Sarakham Province

Abstract

Background and Objective:  Pneumoconiosis is common occupational lung disease in many developing countries. The agriculture is the main occupation of workers in Thailand, estimated 24.1 million workers are agriculturist. Almost agriculturists are informal workers so they are not covered by the legal medical surveillance and occupational compensation.  The agriculturists exposed to occupational hazardous espacially inorganic dusts. There is the study about the relationship between agriculture mineral dust and occupational pneumoconiosis among the young farm workers. The result shows pneumoconiosis 20.9% among farm workers. Prevention is most important and needs to be implemented. This report presents a case of suspected occupational pneumoconiosis in a 47-year-old male due to prolonged occupational soil dust exposure.

Method:  The clinical symptoms and occupational history were taken from the patient during admission period.  The laboratory data such as blood test, sputum gram stain, sputum AFB and sputum cytology were assessed. The chest x-ray and Computed tomography (CT) of the chest were read by radiologist certificated AIR Pneumo (The Asian Intensive Reader of Pneumoconiosis) according to International Labour Organization classification (ILO classification) system.

Result: A 47-year-old male visited the hospital with clinical presentation included progressive dyspnea, 5 kg weight loss within 1 month, no fever and left thyroid gland nodule. A chest X-ray revealed bilateral reticulonodular infiltration but sputum specimens for acid-fast bacilli stain were negative. The patient had a history of prolonged occupational soil-dust exposure from his job harvesting cassava using a backhoe and transferring them to a truck. He was therefore heavily and directly exposed to soil/sand-dust. His chest X-ray revealed perfusion 3/3+, bilateral mixed irregular linear and small nodular opacities, large opacity type A and emphysematous change compatible with pneumoconiosis. Computed tomography (CT) of the chest revealed multiple pulmonary nodules in both lungs with small mediastinal adenopathy, multiple subpleural blebs in both lungs and pulmonary emphysema in both lower lobes. The sputum cytology revealed a few squamous epithelials and inflammatory cells. A lung biopsy was not performed due to the patient’s failing respiratory condition. According to the chest CT and chest X-ray together with exclusion of metastatic lungs and the history of prolonged and heavy exposure to soil/sand-dust, the diagnosis from expert opinion is propable case of  occupational pneumoconiosis.

Conclusion:  An agriculture worker presented with chronic interstitial lung disease; for which a diagnosis of pneumoconiosis was probable, due to prolonged occupational exposure to soi/sand-dust. Similar cases might have occurred but lack of awareness of occupational history-taking may be the cause of under-reporting.  A prevention program and hazard notification is therefore needed for agriculture workers in order to prevent this type of occupational disease.  A medical surveillance program and proper personal protective equipment needs to be formalized and implemented.