Conjunctival Actinic Granuloma: A Clinicopathological and Immunohistochemical Study With a Review of the Literature and a Differential Diagnosis

Ophthalmic Plast Reconstr Surg. 2021 Nov-Dec;37(6):571-575. doi: 10.1097/IOP.0000000000001950.

Abstract

Purpose: To document a case of actinic granuloma (AG) of the conjunctiva, provide an extensive histopathologic and immunohistochemical description, review previously reported cases, and supply a differential diagnosis.

Methods: Both a retrospective chart review and comprehensive literature review were performed. The distinctive histopathologic pattern of the current case was defined with histochemical and immunohistochemical stains (CD163, p63, and a Verhoeff-Van Gieson elastic stain). Clinical follow up was obtained.

Results: A granulomatous process composed of CD163-positive mononuclear epithelioid cells and multinucleated giant cells was characterized by displaced extracellular actinic-related elastic fibers to the base of the lesion. Small elastic fibers were phagocytosed in epithelioid cells. Pseudoepitheliomatous hyperplasia of the overlying squamous epithelium was present; p63 assisted in defining the squamous proliferation and highlighted its noninvasive nature. Conjunctival AGs, according to the literature review, occur almost exclusively in young females, clinically manifest as nodular foci with painless injection over the course of weeks, and histologically featured granulomatous inflammation and elastophagocytosis. The etiology of this entity is likely multifactorial, but its genesis revolves around actinic injury.

Conclusion: AGs of the conjunctiva have likely been an underreported entity in the past. The authors' review underscores the importance of including conjunctival AGs in the differential diagnosis of painless, subacute injected masses of the perilimbal conjunctiva. While it is benign, histopathologically separating AGs from neoplasia and other mimickers such pinguecula, foreign body granulomas, allergic, or rheumatoid nodules is essential for optimal management.

Publication types

  • Case Reports
  • Review

MeSH terms

  • Conjunctiva
  • Conjunctival Diseases* / diagnosis
  • Diagnosis, Differential
  • Female
  • Granuloma, Foreign-Body*
  • Humans
  • Retrospective Studies