What is Ranne complex?
Necrotic material undergoing calciﬁcation
The stage is seen in the formation of granuloma
Central necrosis surrounded by lymphocytes
All of the above
The central part of the TB lesion contains caseous, soft, and cheesy necrotic material (caseous necrosis). This necrotic material may undergo calcification at a later stage called Ranne complex, in the lung parenchyma and hilar lymph nodes in few cases.
Key concept:
Necrotic material undergoing calciﬁcation which is seen in TB is known as Ranne complex.
Ref: Shafer's textbook of oral pathology 7th edition page 320