Skin nontumor
Dermal granulomatous and necrobiotic reaction patterns
Foreign body reaction

Topic Completed: 1 June 2015

Minor changes: 11 November 2020

Copyright: 2002-2021,, Inc.

PubMed Search: Foreign body reaction [title]

Ifeoma U. Perkins, M.D.
Lauren N. Stuart, M.D., M.B.A.
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Cite this page: Perkins IU, Gardner JM, Stuart LN. Foreign body reaction. website. Accessed August 2nd, 2021.
Definition / general
  • Granulomatous inflammatory changes due to the presence of foreign / exogenous material
  • Offending agents may be grouped as follows:
    • Iatrogenic: talc, suture, surgical adhesive, injectable prescription drugs
    • Cosmetic: silicon, lipid, zirconium, cutaneous bleaching agents, bovine collagen, injectable fillers including hyaluronic acid and many others
    • Traumatic: metallic or non metallic splinters, shrapnel, arthropod bite / mouth parts, sea urchin spine, cactus glochids / spines, hair or keratin from ruptured cysts or follicles
    • Occupational: beryllium, silver, silica, hair (groomers or hair dressers / barbers)
    • Self inflicted: tattoos, mercury, injected recreational drugs, food particles, injected mineral oil or paraffin (for attempted cosmesis) (Clin Dermatol 1991;9:157, Am J Dermatopathol 2014;36:409, Dermatology 2014;228:14, Facial Plast Surg 2014;30:615)
  • Varies widely depending on type of foreign material
  • Most commonly presents at site(s) of initial cutaneous injury
  • Rare "migratory" granulomas are due to visible dermatologic lesions remote from initial site of injury (Ann Diagn Pathol 2015;19:10)
  • Exogenous material enters skin via disruption of epidermis (e.g. penetrating injury, injection, surgical manipulation, etc.)
  • Exogenous material is recognized as foreign by antigen presenting cells (tissue macrophages), which surround the material to quarantine it from surrounding uninvolved tissue
Clinical features
  • Variable including localized erythema, induration, pigment alteration, nodules / papules at site(s) of cutaneous injury
  • Over time, lesions may become ulcerated and colonized secondarily by bacteria
  • Deep fungal or bacterial infection and abscess may develop if foreign material was contaminated with fungal organisms (e.g. wood splinters)
  • Lesion may heal only to later become painful and ulcerate with extrusion of foreign material (e.g. transepidermal elimination of suture material long after surgery)
  • Foreign material may migrate via lymphatics to regional lymph nodes, leading to nodal granulomas and palpable lymphadenopathy
Radiology description
  • Utility is based upon features of foreign body (e.g. composition, size, orientation, duration of its presence) and anatomic site
  • Plain radiographs (Xrays) may visualize metallic substances more readily than nonmetallic agents
  • Ultrasonography may be useful to visualize and remove lesions in extremities
  • Computed tomography (CT) and magnetic resonance (MR) are less readily available and more costly; MR may be dangerous if foreign material is metallic and magnetic (J Emerg Med 2014;47:e43, J Eur Acad Dermatol Venereol 2012;26:292)
Case reports
Microscopic (histologic) description
  • Well formed, often non caseating granulomas consisting of histiocytes, usually epithelioid with central foreign body
  • Granulomas are surrounded by variable amounts of lymphocyte predominant chronic inflammation and reactive dermal fibrosis
  • Foreign body is often refractile but may or may not be polarizable; examination with polarized light is useful component of granulomatous dermatitis workup
  • PAS and GMS stains may be useful to rule out secondary deep fungal infection
Microscopic (histologic) images

Images hosted on other servers:

Multinucleated giant cells engulfing suture

Due to wooden splinters

Due to tattoo pigment

Positive stains
  • CD68: stains multinucleated giant cells
  • PAS-D, GMS and AFB: may be positive for microorganisms in infected granulomas
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