Lymphoid hyperplasia is the rapid growth proliferation

Cell growth

The term cell growth is used in the contexts of cell development and cell division . When used in the context of cell division, it refers to growth of cell populations, where one cell grows and divides to produce two "daughter cells"...

 of normal cells that resemble lymph tissue.

Lymph Node Anatomy

The lymph node is a round or reniform organ that is usually no larger than 1cm in diameter. It is composed of a cortex, paracortex, and medulla with sinuses distributed throughout. The paracortex is known as the T-cell zone due to the presence of T-cells, and the cortex is composed of follicles of B cells and is known as the B-cell zone. Each of these locations can undergo hyperplasia.

Follicular Hyperplasia

Follicular hyperplasia is a stimulation of the B cell compartment. It is caused by an abnormal proliferation of secondary follicles and occurs principally in the cortex without broaching the lymph node capsule. The follicles are cytologically polymorphous, are often polarized, and vary in size and shape. Follicular hyperplasia must be distinguished from follicular lymphoma (bcl-2 protein is expressed in neoplastic follicles, but not reactive follicles).

Paracortical Hyperplasia

Paracortical hyperplasia in the preferential stimulation of the T cell compartment. It is caused by an abnormal expansion of the interfollicular zones but is confined within the lymph node capsule. The population of the compartment is cytologically polymorphous. Paracortical hyperplasia may be accompanied by vascular proliferation. Must be distinguished from monomorphous T cell lymphoma.

Sinus Hyperplasia

Sinus hyperplasia is the preferential stimulation of the histiocytic (tissues macrophage) compartment. Histological features include distention or engorgement of both subscapular and inatraparenchymal sinuses by benign histiocytes which may be hemophagocytic. Sinus hyperplasia may be associated with non-hematolymphoid malignancy.

Complications

It is one common source of appendicitis

Appendicitis

Appendicitis is a condition characterized by inflammation of the appendix. It is classified as a medical emergency and many cases require removal of the inflamed appendix, either by laparotomy or laparoscopy. Untreated, mortality is high, mainly because of the risk of rupture leading to...

, as it may cause an obstruction of the appendiceal lumen, resulting in the subsequent filling of the appendix with mucus, causing it to distend and internal pressure to increase.