Ghon's complex

Ghon's complex, sometimes called Ranke's complex is a lesion seen in the lung that is caused by tuberculosis. The two alternative names come from the scientists Karl Ernst Ranke, or Anton Ghon, respectively. [ [http://www.whonamedit.com/synd.cfm/3647.html Ghon's primary lesion] Whonamedit.com, Accessed 21 January 2008] [cite journal |author=Ober WB |title=Ghon but not forgotten: Anton Ghon and his complex |journal=Pathol Annu |volume=18 Pt 2 |issue= |pages=79–85 |year=1983 |pmid=6371678] The lesions consist of a calcified focus of infection and an associated lymph node. These lesions are particularly common in children and can retain viable bacteria, so are sources of long-term infection and may be involved in reactivation of the disease in later life. [cite journal |author=Curvo-Semedo L, Teixeira L, Caseiro-Alves F |title=Tuberculosis of the chest |journal=Eur J Radiol |volume=55 |issue=2 |pages=158–72 |year=2005 |pmid=15905057 |doi=10.1016/j.ejrad.2005.04.014]

Specifically, the Ghon's complex is a combination of the "Ghon's focus" (area of initial infection by airborne bacillus) and a lymphatic lesion. Approximately two to three weeks after the Ghon's focus has developed, the area undergoes "caseous necrosis" (cheeselike). Free tubercle bacilli, or bacilli within macrophages drain out from the area towards the affected lungs' lymph nodes. It is in this location, at the lymph nodes, that the bacilli will form caseous granulomas. This, in combination with the initial area of infection, will make up the Ghon's complex. Typically these areas heal with calcification visible on chest X-ray, with the two causes virtually indistinguishable.

ee also

*Ghon focusGross appearance there is a small tan-yellow subpleural granuloma in the mid-lung field on the right. In the hilum is a small yellow tan granuloma in a hilar lymph node next to a bronchus

References

*Porth, Carol Mattson. Pathophysiology: Concepts of Altered Health States, 7th edition. Philadelphia: Lippincott Williams & Wilkins, 2005.