A 49-Year-Old Man with Fever and Chronic Cough

A 49 year-old non smoker man from an Iranian rural region residing in Tehran, presented with chronic non-productive cough since 7 months ago. He worked in a dairy farm located in Tehran and had a 7-year history of contact with chemical agents. He had fever and night sweats since 3 months ago with episodes of myalgia and arthralgia and a 10 kg weight loss. He did not give any history of hemoptysis or dyspnea. During this period he was treated with multiple courses of antibiotics including ceftriaxone and azithromycin without any improvement. He was also under a regimen of clonazepam and amitriptyline for a major depressive disorder. On physical examination, his vital signs were stable with no respiratory distress. All physical findings were normal, except for an oral temperature of 38.2˚C and end inspiratory crackles in lower lobes of both lungs. Complete blood count revealed a PMN dominant leukocytosis. Blood biochemistry, liver function tests and urinalysis were normal. Erythrocyte sedimentation rate (ESR) for the first hour was 125mm. PPD test was nonreactive. Three consecutive sputum smears and cultures plus sputum polymerase chain reaction (PCR) were all negative for mycobacterium tuberculosis. Severe restrictive pattern was observed in pulmonary function test. Transthoracic echocardiography was reported to be normal. Chest x-ray (Figure 1) and thoracic spiral CT scan (Figure 2) were performed. Ground glass opacity and infiltration in lingula, right middle lobe and both lower lobes with mild cardiomegaly and small sized mediastinal adenopathy were revealed on CT scan.