A 43-year-old male, working as a sand blaster for the past 13 years, presented with fever, cough, breathlessness, and right-sided pleuritic type of chest pain of a duration of 2 months. He had been evaluated in another hospital where he was diagnosed as sputum-negative pulmonary tuberculosis based on contrast-enhanced computerized tomogram (CECT) chest and bronchoscopy findings. The computerized tomogram (CT) done 3 months prior to presentation showed nonspecific patchy parenchymal opacities [Figure 1a]. He was started on antitubercular treatment (ATT). But his symptoms worsened and repeat CECT of the chest done a month later revealed features suggestive of nonresolving pneumonia. There were larger and newer parenchymal opacities, predominantly in the lung bases. His breathlessness had worsened since 2 days and on admission his saturation (SpO2) was 70% on room air and 90% with 5 L oxygen through Hudson's mask.
On examination, he was emaciated and had bilateral end-expiratory crepitations. His erythrocyte sedimentation rate (ESR) was 86 mm/h with leukocytosis. His two sputum samples were negative for acid-fast bacilli (AFB) on Ziehl-Neelsen (ZN) stain. High-resolution CT (HRCT) of the chest showed bilateral middle and lower lobe ground-glass opacities with left lower lobe consolidation [Figure 1b and c]. CT-guided biopsy of the left lower lobe lesion was performed [Figure 1d] to rule out the possibility of malignancy and histopathological examination showed features of interstitial pneumonia with fibrosis.
The papanicolaou (PAP) stain on bronchial lavage revealed benign squamous cells, pigment-laden macrophages, and extensive acute inflammatory cell infiltrate [Figure 2a and b]. The lavage fluid was positive for AFB as demonstrable by ZN stain. Detection of numerous birefringent silica particles under polarizing microscope in the bronchial lavage [Figure 2c and d], otherwise not appreciable on PAP stain, clinched the primary diagnosis of silicosis with associated tuberculosis.
Initiation of ATT was done as per the patient's body weight. However, his hypoxia persisted and he was discharged on domiciliary oxygen. Repeat chest radiograph at end of 1 month did not show any radiological improvement. His respiratory failure persisted and he was continued on the domiciliary oxygen.