Follicular hyperplasia

Follicular hyperplasia (or "reactive follicular hyperplasia" or "lymphoid nodular hyperplasia") is a type of lymphoid hyperplasia. It is caused by a stimulation of the B cell compartment.^[1] 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.^[2] Follicular hyperplasia is distinguished from follicular lymphoma in its polyclonality and lack of bcl-2 protein expression, whereas follicular lymphoma is monoclonal, and does express bcl-2^[3]).

Causes

Some specific reactive lymphadenopathies with a predominantly follicular pattern:^[4]

• Rheumatoid arthritis
• Sjogren syndrome
• IgG4-related disease (IgG4-related lymphadenopathy) ^[5]
• Kimura disease
• Toxoplasmosis
• Syphilis
• Castleman disease
• HIV-associated lymphadenopathy
• Progressive transformation of germinal centers (PTGC)

References

1. ↑ Weiss, L. M.; O'Malley, D (2013). "Benign lymphadenopathies". Modern Pathology. 26 Suppl 1: S88–96. PMID 23281438. doi:10.1038/modpathol.2012.176. 
2. ↑ Drew, Torigan; et al. "Lymphoid hyperplasia of stomach". American Journal of Roentgenology. Retrieved 2 November 2012. 
3. ↑ Sattar, Husain (2016). Fundamentals of Pathology. Chicago. ISBN 9780983224624. 
4. ↑ Weiss, L. M.; O'Malley, D (2013). "Benign lymphadenopathies". Modern Pathology. 26 Suppl 1: S88–96. PMID 23281438. doi:10.1038/modpathol.2012.176. 
5. ↑ John H. Stone; Arezou Khosroshahi; Vikram Deshpande; et al. (October 2012). "Recommendations for the nomenclature of IgG4-related disease and its individual organ system manifestations". Arthritis & Rheumatism. 64 (10): 3061–3067. PMID 22736240. doi:10.1002/art.34593.