O OftalmopediaAn open ophthalmology reference ⌕

Phlyctenular keratoconjunctivitis

AI overview

Phlyctenular keratoconjunctivitis is an inflammatory syndrome caused by a delayed (aka type-IV) hypersensitivity reaction to one or more antigens.

Key points
  • It is caused by a type-IV hypersensitivity reaction to antigens, usually bacterial proteins from Staphylococcus aureus
    source quote
    an inflammatory syndrome caused by a delayed (aka type-IV) hypersensitivity reaction to one or more antigens. The triggering antigen is usually a bacterial protein (particularly from Staphylococcus aureus )
  • Other possible triggers include viruses, fungi (particularly Candida albicans), or nematodes
    source quote
    but may also be a virus, fungus (particularly Candida albicans ), or nematode
  • The syndrome is characterized by phlyctenules on the cornea and/or conjunctiva
    source quote
    The syndrome is marked by the appearance of characteristic lesions, known as phlyctenules , on the cornea and/or conjunctiva.
  • Lesions are small raised nodules, pinkish-white or yellow, which may ulcerate or necrose
    source quote
    small (1 - 3 [ 1 ] or 1 - 4 [ 2 ] mm) raised nodules, pinkish-white or yellow in color, which may ulcerate (or, more rarely, necrose) and are often surrounded by dilated blood vessels
  • Corneal lesions are triangular with base at limbus and apex pointing toward center of cornea
    source quote
    Corneal lesions are usually triangular in shape, with the base at the limbus and the apex pointing towards the center of the cornea.
Symptoms
  • Irritation
    source quote
    Irritation
  • Discomfort or pain
    source quote
    Discomfort or pain
  • Foreign-body sensation
    source quote
    Foreign-body sensation
  • Tearing
    source quote
    Tearing
  • Blepharospasm
    source quote
    Blepharospasm
  • Photophobia
    source quote
    Photophobia
  • Mucopurulent discharge (rarely)
    source quote
    Mucopurulent discharge (rarely)
  • Pain and photophobia are more likely when cornea is affected
    source quote
    In cases where the cornea is affected, pain and photophobia are more likely
Diagnosis
  • Diagnosis is based on clinical findings of corneal lesion or corneal ulceration
    source quote
    Clinical findings of corneal lesion or corneal ulceration.
Treatment
  • Primary treatment is corticosteroid eye drops such as prednisolone acetate or loteprednol
    source quote
    primarily treated with application of an appropriate corticosteroid eye drop, such as prednisolone acetate (Pred Forte) or loteprednol (Lotemax)
  • Loteprednol is increasingly preferred due to lower risk of elevating intraocular pressure
    source quote
    Loteprednol is increasingly preferred due to its lower risk of elevating intraocular pressure
  • The causative agent should be identified; Staphylococcus aureus is primary suspect, along with Mycobacterium tuberculosis in endemic areas and Chlamydia trachomatis
    source quote
    Staphylococcus aureus is usually the primary suspect, along with Mycobacterium tuberculosis in areas where TB is endemic , followed by Chlamydia trachomatis
  • Active bacterial infections may be treated with topical antibiotic or combination antibiotic-steroid eye drop such as tobramycin/dexamethasone
    source quote
    Active bacterial infections may be treated with a topical antibiotic or a combination antibiotic-steroid eye drop, such as tobramycin/dexamethasone (Tobradex)
  • Oral tetracycline such as doxycycline may be used for systemic or severe infections
    source quote
    An oral tetracycline antibiotic (such as doxycycline ) may be used in systemic or particularly severe/intractable infections.
  • Erythromycin may be an effective alternative, especially in pediatric cases where tetracycline side effects are unacceptable
    source quote
    Erythromycin may be an effective alternative, especially in pediatric cases where the side effects of tetracyclines are unacceptable.
  • Artificial tears can reduce dryness and discomfort from corneal lesions
    source quote
    Artificial tears can reduce dryness and discomfort from corneal lesions.
  • Dark sunglasses can mitigate photophobic discomfort
    source quote
    Photophobic discomfort can be mitigated with dark sunglasses
Red flags
  • Corneal scarring can occur and potentially impair vision
    source quote
    corneal scarring can occur (potentially impairing vision)
Prognosis

Corneal scarring can occur, potentially impairing vision.

AI-synthesized from the Wikipedia article “Phlyctenular keratoconjunctivitis”. Not medical advice. Verify source →
Phlyctenular keratoconjunctivitis
Other namesPhlyctenulosis
Illustration of a corneal phlyctenule
SpecialtyNeurology 

Phlyctenular keratoconjunctivitis is an inflammatory syndrome caused by a delayed (aka type-IV) hypersensitivity reaction to one or more antigens. The triggering antigen is usually a bacterial protein (particularly from Staphylococcus aureus), but may also be a virus, fungus (particularly Candida albicans), or nematode.[1]

In cases where the cornea is affected, pain and photophobia are more likely,[1][2] and corneal scarring can occur (potentially impairing vision).[1]

The syndrome is marked by the appearance of characteristic lesions, known as phlyctenules, on the cornea and/or conjunctiva. These usually manifest as small (1 - 3[1] or 1 - 4[2] mm) raised nodules, pinkish-white or yellow in color, which may ulcerate (or, more rarely, necrose) and are often surrounded by dilated blood vessels. Corneal lesions are usually triangular in shape, with the base at the limbus and the apex pointing towards the center of the cornea.[1][2][3]

Clinical findings of corneal lesion or corneal ulceration.

The symptoms of phlyctenular keratoconjunctivitis are primarily treated with application of an appropriate corticosteroid eye drop, such as prednisolone acetate (Pred Forte) or loteprednol (Lotemax). Loteprednol is increasingly preferred due to its lower risk of elevating intraocular pressure. The corticosteroid suppresses the immune response, reducing inflammation and improving most symptoms.[1][2][4]

The causative agent (i.e. the source of the antigen that triggered the hypersensitive immune response) should also be identified. Staphylococcus aureus is usually the primary suspect, along with Mycobacterium tuberculosis in areas where TB is endemic, followed by Chlamydia trachomatis. Active bacterial infections may be treated with a topical antibiotic or a combination antibiotic-steroid eye drop, such as tobramycin/dexamethasone (Tobradex).[1] An oral tetracycline antibiotic (such as doxycycline) may be used in systemic or particularly severe/intractable infections.[2][4] Erythromycin may be an effective alternative, especially in pediatric cases where the side effects of tetracyclines are unacceptable.[4]

Artificial tears can reduce dryness and discomfort from corneal lesions.[2] Photophobic discomfort can be mitigated with dark sunglasses.[4]

  1. 1 2 3 4 5 6 7 8 9 10 11 Onofrey, Bruce E.; Skorin, Leonid; Holdeman, Nicky R. (2005-01-01). Ocular Therapeutics Handbook: A Clinical Manual. Lippincott Williams & Wilkins. ISBN 9780781748926. ... including virus, fungus, chlamydia, and nematodes.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 Malinovsky, Victor (2006). "Phylctenular Ulcers" (PDF). Indiana University School of Optometry. Indiana University. Archived from the original (PDF) on 2017-12-15. Retrieved 2017-01-18.
  3. ↑ "Contact Lens Spectrum - treatment plan". www.clspectrum.com. Archived from the original on 2017-02-02. Retrieved 2017-01-18.
  4. 1 2 3 4 "Volume 4, Chapter 8. Phlyctenular Keratoconjunctivitis". www.oculist.net. Retrieved 2017-01-18.