A 53-year-old Caucasian female was admitted to a referral pulmonary institute after the chest X-ray showed infiltrations in the lungs and enlarged hilus on both sides. The chest X-ray was performed as a preoperative assessment for the scheduled thyroidectomy due to the euthyroid nodular goiter. The patient experienced a gradual enlargement of the thyroid over the past 4-5 months that caused difficulties with breathing and swallowing. Among the other complaints, she cited a dry cough in the last 2 months. She started treatment with antihypertensives 2 months earlier, while denying having any other comorbid conditions. The patient reported a positive family history of malignant lung and cardiovascular diseases, while her psycho-social history was unremarkable. Physical examination revealed an enlarged right lobe of the thyroid gland, while other findings were not abnormal.
Blood laboratory analysis at the admission revealed elevated values of serum angiotensin-converting enzyme (ACE) and serum calcium, while other biochemical parameters, including the value of calcium in 24-h urine, were within reference range (Table 1). High-resolution computed tomography (HRCT) of the chest revealed numerous bilateral micronodular lesions in the pulmonary parenchyma and mediastinal and hilar lymphadenopathy (Figures 1A-C). An inhomogeneous, predominantly hypodense abnormality in the enlarged right thyroid lobe, 30x28 mm in diameter, was also observed (Figure 1D). No nodular changes were visible inside the left lobe. Pulmonary function tests and gas exchange during rest and exercise were both preserved. A bronchoscopy was performed. Histopathological examination confirmed non-necrotizing granulomatous inflammation of pulmonary parenchyma and lymph glands (Figures 2A,B). The ultrasound examination of the upper abdomen and the ophthalmological examination did not find any evidence of sarcoidosis extension. Tuberculosis was excluded since acid-fast staining of the patient's sputum and lung biopsies revealed no acid-fast bacilli, while cultures on Mycobacterium tuberculosis and other mycobacteria later yielded negative results. Other causes of granulomatous inflammation, such as fungal infection, were excluded as well, since sputum and biopsies' fungal cultures grew negative, while pathohistological staining of lung biopsies was negative for fungal infection. Following that, steroid therapy was administered, with a 40 mg/day (0.5 mg/kg) starting dose of oral prednisone. After 3 months of therapy, there was a radiological improvement on patient's chest X-ray, with ACE levels in the reference range, while only minor changes in the size of the thyroid gland were observed. Considering that, a video-assisted lobectomy of the right thyroid lobe was performed shortly after. Histopathological examination of the thyroid tissue revealed non-necrotizing granulomas consistent with sarcoidosis (Figures 2C,D). Substitution therapy with 75 mcg/day oral levothyroxine was prescribed, along with the slow dose tapering of oral steroids over the next 9 months, when oral steroids were stopped (Figure 3). After that, the patient was asymptomatic, without visible changes on chest X-ray and no biochemical evidence of the disease's activity. After being attentively monitored for the following 12 months, the patient stopped showing up for her scheduled checkups.