A 79-year-old man presented to his primary physician with a 3-month history of weight loss, fever, fatigue, night sweats, and cough. He is a former smoker. A recent HIV test was negative. A CT scan of the chest reveals a 3 cm lesion in the lower lobe of the left lung and calcification around the left lung hilus. A sputum smear was positive for acid fast organisms. These findings are most consistent with which of the following:
1.Primary tuberculosis
2.Adenocarcinoma
3.Miliary tuberculosis
4.Coccidioidomycosis infection
5.Secondary tuberculosis
exp:
The patient’s positive acid-fast sputum sample accompanied by a characteristic Ghon complex likely represent primary tuberculosis.
Mycobacterium tuberculosis is an acid-fast bacteria known to be the causative agent of tuberculosis. Transmission relies on inhalation of small-particle aerosols covered in the bacteria. Primary tuberculosis is characterized by a fibrocavitary disease of the middle or lower lobes of the lung with/without involvement of hilar/mediastinal nodes. Together, these findings are termed a Ghon complex when visible on chest radiograph.
Illustration A shows a chest radiograph of a patient with a Ghon complex and calcified hilar lymph nodes.
Illustration B shows a ghon complex in a gross specimen of lung. You can appreciated the calcifications within the complex.