PATHOLOGY

Detailed explanation-1: -Granuloma formation may be divided into four phases: initiation, accumulation, effector, and resolution. Very little is known about the initiation phase, but macrophages migrate into the site of infection and initiate granuloma formation.

Detailed explanation-2: -Granulomas can be composed of macrophages (foreign body reaction), epithelioid cells (immune granulomas of sarcoidosis, tuberculosis), or Langerhans’ cells (histiocytosis X).

Detailed explanation-3: -The granuloma contains mostly blood-derived macrophages, epithelioid cells (differentiated macrophages) and multinucleated giant cells (also known as Langhans giant cells), surrounded by T lymphocytes [8, 9]. Caseous granulomas are typical of tuberculosis.

Detailed explanation-4: -The granulomatous inflammatory response is a special type of chronic inflammation characterised by often focal collections of macrophages, epithelioid cells and multinucleated giant cells.