Eye
Conjunctiva
Conjunctivitis
Trachoma
Author: Deepali Jain, M.D.
Last author update: 1 November 2013
Last staff update: 29 December 2020
Copyright: 2004-2025, PathologyOutlines.com, Inc.
PubMed Search: Trachoma [title] inclusion conjunctivitis
Table of Contents
Epidemiology | Sites | Etiology | Clinical features | WHO grading system | Laboratory | Treatment | Clinical images | Microscopic (histologic) description | Microscopic (histologic) imagesCite this page: Jain D. Trachoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/eyetrachoma.html. Accessed January 10th, 2025.
Epidemiology
- Major cause of blindness outside US (Wikipedia: Trachoma [Accessed 26 April 2018], eMedicine: Trachoma [Accessed 26 April 2018])
- 40 million people affected worldwide (WHO); 1.2 billion people live in endemic areas
- Associated with poverty, overcrowding, direct contact, flies and poor hygiene
Sites
- Entire conjunctiva but most prominent on upper tarsus
Etiology
- Caused by Chlamydia trachomatis, serovars A, B, Ba, and C of Chlamydia trachomatis
- Serovars D-K associated with adult inclusion conjunctivitis
- Causes scarring of corneal tissue
Clinical features
- Active trachoma:
- Most common in preschool children
- Mixed follicular / papillary conjunctivitis associated with a mucopurulent discharge
- Superior epithelial keratitis and pannus
- Cicatricial trachoma:
- Most common in middle age adults
- Linear or stellate conjunctival scars (mild cases)
- Broad confluent scars or Arlt lines in severe cases
- Adult inclusion conjunctivitis:
- Acute mucopurulent conjunctival infection
- Superior limbal follicles may resolve to leave a row of shallow depressions (Herbert pits)
- Trichiasis, distichiasis, corneal vascularization and cicatricial entropion
- Corneal opacification
- Dry eye
WHO grading system
- TF:
- 5 or more follicles on the upper conjunctiva
- Follicles must be at least 0.5 mm in diameter and are round, white, paler than surrounding conjunctiva
- TI:
- Intense trachomatous inflammation
- Tarsal conjunctiva appears red, rough and thickened, obscuring more than half of the normal, deep, tarsal vessels
- Numerous follicles are partially covered by thickened conjunctiva
- TS:
- Scarring and fibrosis of tarsal conjunctiva due to severe or chronic trachoma
- Also called cicatricial trachoma
- Scars are visible as white lines, bands or sheets
- TT:
- Trichiasis defined as at least one eyelash that rubs on eyeball due to entropion of lid
- CO:
- Corneal opacity
- Eyelashes have abraded and damaged cornea, causing corneal opacity and visual loss
Laboratory
- Dacron swab culture
- RNA and DNA based nucleic acid amplification tests (Curr Opin Ophthalmol 2012;23:288)
Treatment
- World Health Organization has instituted its SAFE (surgery, antibiotics, facial cleanliness, and environmental improvement) program (Trop Med Int Health 2010;15:673, Lancet 2008;371:1945)
Clinical images
Images hosted on other servers:
WHO grading
Presence of five or more follicles
Thickening of the tarsal conjunctiva
Scarring in the tarsal conjunctiva
Evidence of recent removal of inturned eyelashes
Corneal opacity over the pupil
Microscopic (histologic) description
- Stage I:
- Conjunctival inflammatory infiltrates (lymphoid follicles and diffuse infiltrates)
- Followed by pannus formation (fibrovascular tissue in conjunctival and corneal stroma) with Chlamydia elementary bodies and larger basophilic initial bodies seen
- Also lymphocytes, plasma cells, neutrophils
- Stage II:
- Florid inflammation, more follicles, epithelial thickening, severe pannus
- Macrophages with ingested debris (Leber cells) in conjunctiva
- Stage III:
- Scarring
- No follicles
- Cicatricial entropion (inversion of upper lid)
- Misdirected lashes (trichiasis)
- Stage IV:
- Arrest of disease due to entropion and trichiasis but with continuing corneal damage and infection
Microscopic (histologic) images
Images hosted on other servers:
Chlamydia inclusions
