“Miliary lung parenchymal opacities” as presenting feature of metastatic papillary type of thyroid malignancy: It’s not tuberculosis always!

Abstract

Pulmonary tuberculosis (TB) is the most common cause of mortality and morbidity in South East Asia due to infective causes and tops the list of all infectious etiologies in India. Radiological presentations in pulmonary TB are diverse with the most common in them, which are nodules, consolidation, cavitation, and lung parenchymal destruction with or without collapse and consolidation. In this case report, a 31-year-old female presented with constitutional symptoms with miliary opacities in chest X-ray without microbiological evidence for TB in smear microscopy or nucleic acid amplification tests. She was treated as a case of miliary TB with antituberculosis treatment (ATT) on two occasions in the past 2 years as an “X-ray-positive case” on the basis of symptoms and chest radiology findings. She was never shown any clinical and radiological response in the past 1½ years in spite of satisfactory ATT adherence and compliance. After retrospective analysis of this case at our center, we have documented worsening of radiological findings and chest high-resolution computed tomography conformed miliary nodules and not typical miliary mottling favoring TB. We have noted right thyroid enlargement with a nodule in contrast tomography of neck. Fine-needle aspiration cytology confirmed as papillary carcinoma of the thyroid. We have confirmed this case as miliary metastasis due to primary thyroid malignancy. Miliary metastasis should be considered in cases with atypical radiological and clinical presentations with negative microbiological workup. No empirical ATT should be offered in the era of highly sensitive nucleic acid amplification tests and the term “X-ray-positive with negative microbiological tests” should be phased out.