The first report of the Ghon complex was by Anton Ghon (1866-1936), an Austrian pathologist who described primary tuberculosis to have the findings of a pulmonary lesion with regional lymph involvement caused by Mycobacterium tuberculosis. Primary pulmonary tuberculosis (TB) infection on chest radiography commonly presents with either one of the following four presentations: parenchymal disease, lymphadenopathy, pleural effusions, miliary tuberculosis, and the possibility of any combination of these. Specifically, in parenchymal disease, primary TB is hallmarked with a pulmonary lesion (also known as a Ghon lesion or Ghon focus) and affected draining lymph node adenopathy forming the Ghon's complex.
The Ghon complex is a non-pathognomonic radiographic finding on a chest x-ray that is significant for pulmonary infection of tuberculosis. The location of the Ghon's focus is usually subpleural and predominantly in the upper part of the lower lobe and lower part of the middle or upper lobe. The predilection for this area is because the ventilation is best in this region, and the most frequently encountered route of infection is through the respiratory tract. Radiographic findings of the Ghon focus may include parenchymal scarring of the lung tissue, lesion cavitation, or lobar consolidation, as seen in Figures 1, Figure 2, and Figure 3. The Ghon complex should not be confused with the Ranke complex. The Ghon complex precedes the development of a Ranke complex, in that a Ghon complex is seen in untreated primary pulmonary tuberculosis infection with Ghon lesion fibrosis while the Ranke complex is a result of the healing of a primary tuberculosis Ghon complex characterized by a calcified Ghon lesion and calcified mediastinal lymph nodes.