A 29-year-old man presented with complaints of fever and cough of 1 month's duration. There was no breathlessness, chest pain, hemoptysis, anorexia, or weight loss. There was no history of exposure to farm dust, metallic dust, fumes, or animal dander. The patient did not keep any pets or birds at home, and denied having any addictions. On examination, the pulse rate was 90 beats per min, respiratory rate 18 breaths per min, blood pressure 110/80 mmHg, and temperature 100 F. Pulse oximetric saturation was 98% while breathing room air. Auscultation of the chest revealed a few inspiratory crackles in both the lung bases. The rest of the physical examination was unremarkable.
The complete blood count and renal function tests were normal [Table 1]. There was elevation of the liver enzymes, with normal bilirubin and alkaline phosphatase (bilirubin 0.7 mg/dL, aspartate transaminase 66 U/L, alanine transaminase 88 U/L, alkaline phosphatase 126 U/L). The coagulation profile was normal. Urine analysis was normal, and blood and urine cultures were sterile. The tuberculin skin test was positive with an induration of 13 mm. The chest radiograph showed diffusely distributed nodules in bilateral lung fields. Computed tomography of the chest showed randomly distributed tiny nodules (1-2 mm in size) in both lungs [Figure 1], with mild hepatomegaly and a few subcentimetric lymph nodes at the porta and retroperitoneum. Two possibilities were considered: Disseminated tuberculosis and sarcoidosis. Flexible bronchoscopy and TBLB, both with conventional forceps and cryoprobe, were planned. The procedure was performed in the bronchoscopy suite with local anesthesia and conscious sedation. The heart rate, oxygen saturation, blood pressure, and electrocardiogram (ECG) were monitored throughout the procedure. Continuous oxygen supplementation was provided through a face mask. The flexible bronchoscope (BF-1T180, Olympus, Tokyo, Japan) was introduced through the nose; the airway examination was normal, and subsequently, bronchoalveolar lavage was performed. TBLB was then performed using standard biopsy forceps (FB-19C, Olympus, Japan) from the basal segments of the right lower lobe. Six tissue specimens were obtained. Subsequently, cryo-TBLB was performed. The bronchoscope was introduced orally and maneuvered into the posterior segment of the right lower lobe. The flexible cryoprobe (1.9-mm outer diameter, 900-mm length, ERBE Elektromedizin, Tubingen, Germany) was introduced through the working channel of the bronchoscope into the selected segment and subsequently confirmed under fluoroscopic guidance. The probe was stationed 2 cm away from the chest wall. It was then cooled with nitrous oxide (this reduces the temperature of the probe's tip to -89 C) for 4 s. The entire bronchoscope was then retracted with the frozen lung tissue attached to the probe's tip. As soon as the bronchoscope was withdrawn from the patient, it was handed over to the technical assistant. The tip of the cryoprobe along with the first bronchoscope was immersed in normal saline at room temperature. Thawing resulted in the separation of the specimen from the tip. The specimen was then transferred into formalin. Meanwhile, the operator introduced another bronchoscope (FB-19TV, Pentax, Tokyo, Japan) immediately through the nose. Mild bleeding was visualized. The bronchoscope was immediately wedged into the posterior segment of the right lower lobe for 3 min and then withdrawn. There was no ongoing bleeding. The bronchoscope was subsequently withdrawn from the patient.
Histopathological examination was done by an experienced pulmonary histopathologist. The CB was 0.5 cm in length, while the largest conventional FB specimen was 0.1 cm [Figure 2]. The surface areas of the CB and the FB were 14.18 mm2 and 1.65 mm2, respectively as measured with digital morphometry (Leica QWin version 3, Leica Microsystems Imaging Solutions Ltd, Cambridge, UK). Microscopic examination revealed 24 alveoli in FB and 212 alveoli in CB. Both the specimens revealed the presence of epithelioid cell granulomas with multiple Langhans type of giant cells and surrounding lymphocytes [Figure 3]. While there were nine granulomas in the CB, there was only one granuloma found in FB. The granuloma in the FB was a loose collection of epithelioid cells and did not have any central necrosis. The granulomas found in CB were well formed with Langhans type of giant cells and showed the presence of central necrosis with nuclear debris pointing toward a diagnosis of tuberculosis rather than sarcoidosis. There was no angiitis. Ziehl-Neelsen staining did not reveal acid-fast bacilli in either specimen. There was no artifact in the CB, while the FB showed minor crush artifacts. A diagnosis of pulmonary tuberculosis was made. The patient was started on antituberculosis treatment with oral rifampicin (600 mg), isoniazid (300 mg), pyrazinamide (1500 mg), ethambutol (1000 mg), and pyridoxine (10 mg). Fever abated in 2 weeks and cough disappeared. Chest radiograph showed reduction in the nodular opacities. Currently, at the time of writing, the patient is asymptomatic and under follow-up.
F; Computed tomography of the chest showing multiple random nodules diffusely distributed in both the lung fields.