Keratitis in Sub-Saharan Africa presents a significant challenge due to various factors such as limited access to clean water and sanitation especially in rural areas, high prevalence of infectious diseases, and environmental conditions conducive to eye injuries. Common causes include bacterial, viral, fungal, and parasitic infections, exacerbated by agricultural practices, traditional eye treatments, and poor hygiene. Delayed diagnosis and treatment due to healthcare access issues contribute to higher rates of complications and vision loss. Efforts to improve eye care infrastructure, promote hygiene practices, and enhance education on preventive measures are crucial in addressing keratitis in this region. In addition, traditional eye treatments in some cases makes the disease worse prior to presentation.

    Symptoms of                      keratitis 

1. Eye Pain: Often described as sharp, stabbing, or a sensation of foreign body in the eye.
2. Redness: Conjunctival injection due to inflammation of the cornea.
3. Photophobia: Sensitivity to light, causing discomfort or pain in bright environments.
4. Blurred Vision: Reduced clarity of vision due to corneal involvement and inflammation.
5. Excessive Tearing: Increased tear production as a response to eye irritation.
6. Discharge: Watery or purulent discharge from the eye, depending on the underlying cause of keratitis.
7. Eye Swelling: Periorbital swelling or eyelid edema may occur, especially in severe cases.

             Clinical findings of keratitis

This can vary depending on the underlying cause but commonly include:

1. Blepharospasms excessive blinking/closing of the lids to avoid sensitivity to light
2. Epithelial Defects: Loss of the corneal epithelium, leading to painful erosions or ulcers
3. Conjunctival Injection: Redness of the conjunctiva surrounding the cornea, indicating inflammation. Circumcorneal or circumlimbal injections
4. Corneal Infiltrates: White or greyish infiltrates on the corneal surface indicating inflammatory or infectious processes.
5. Corneal Opacity: Clouding or haziness of the cornea due to inflammation or infection.
6. Corneal Neovascularization: New blood vessel growth towards the cornea as a response to injury or in cases of prolonged inflammation
7. Stromal Keratitis: Inflammation and opacity affecting the deeper layers of the cornea, potentially leading to scarring and vision loss.

Differential Diagnosis 

Differential diagnoses of keratitis in Sub-Saharan Africa include:

1. Bacterial Keratitis: Typically caused by organisms like Staphylococcus aureus, Streptococcus pneumoniae, or Pseudomonas aeruginosa. Risk factors include trauma, use of traditional eye medicines – some people instil urine into their eyes when they have eye problems, poor hygiene contact lens wear that occurs rarely.
2. Fungal Keratitis: Fusarium, Aspergillus, and Candida species are common fungal pathogens. Risk factors include agricultural injuries, trauma with vegetative material, and tropical climate conditions.
3. Viral Keratitis: Herpes simplex virus (HSV) or varicella-zoster virus (VZV) infections, often presenting with dendritic or geographic ulcers. Common in individuals with previous ocular or systemic viral infections.
4. Protozoal Keratitis: Acanthamoeba and microsporidia infections, particularly associated with contaminated water sources or improper contact lens hygiene.
5. Parasitic Keratitis: Acanthamoeba, Onchocerca volvulus (river blindness), and Loa loa (African eye worm) infections, prevalent in areas endemic to these parasites.
6. Non-infectious Keratitis: Chemical burns, autoimmune conditions (e.g., Mooren’s ulcer), and neurotrophic keratitis due to nerve damage.
7. Marginal Keratitis: Associated with immune-mediated conditions such as rosacea or systemic diseases like rheumatoid arthritis.
8. Ocular Surface Disease: Dry eye syndrome, exposure keratitis, and blepharitis, exacerbated by environmental factors and poor ocular hygiene.

                 Investigation  

In Sub-Saharan Africa, investigating keratitis involves a comprehensive approach tailored to the region’s challenges. This includes clinical evaluation focusing on symptoms and ocular findings. Ocular findings including the visual acuity, characteristics of the ulcer whether it has well defined margins or not, size of the ulcer should be measured on slit lamp examination, presence of hypopyon, any corneal thinning or perforations, IOP measurement could be with a non-contact tonometer.

Investigations: anterior segment photography, anterior segment OCT, microbiological testing such as corneal scraping for microscopy, cultures and sensitivity and PCR. 

Access to portable diagnostic equipment and collaboration with microbiologists are crucial. Microscopy can be done at the side labs.

Emphasis on health education and preventive measures can reduce the burden of microbial keratitis and its sequalae. For example, use of traditional eye treatments can be discouraged or stopped via awareness of their detrimental effects to the eyes while other health workers e.g.  community health workers can be trained on identifying ulcers and to commence topical antibiotics prior to referral. 

enhances early detection and effective management of keratitis in resource-limited settings.

       Treatment of keratitis

In Sub-Saharan Africa involves the use of topical antimicrobial agents tailored to the suspected pathogen (bacterial, fungal, viral), which may involve initial admission to administer antibiotics aggressively. Antibiotics is given hourly for the first 48 hours and then continue hourly and adjusted based on the response. Daily review of the patient. Measuring the size of the ulcer is important and then comparing the findings with the initial findings. Compare the findings with the initial anterior segment photography especially if a different clinician is seeing for objective assessment of improvement of not

If it is viral patient would not need to be admitted. Oral acyclovir and topical acyclovir gel would be given in addition to cycloplegics

For fungal oral antifungal can be added.

There is no place for use of steroids it would worsen the ulcers. There’s the SCUT trial that looked at use of steroids but there is no strong evidence it helps. Use of steroids is controversial and reserved for ophthalmologists.  

Supportive care including cycloplegic agents, eye drops to lower IOPs when elevated and artificial tears, oral analgesics can be given 

Surgical interventions such as corneal debridement or transplantation may be necessary in severe cases.

 Regular monitoring, patient education on eye hygiene, and prompt healthcare seeking behaviour are critical for successful management and prevention of complications. 

Access to medications, trained healthcare providers, and supportive infrastructure are essential in optimizing treatment outcomes in this resource-limited setting.

Follow-up of keratitis in Sub-Saharan Africa

This involves regular monitoring to track healing progress, adjust treatment as needed, manage complications like corneal scarring, and support visual rehabilitation. Patient education on medication adherence, eye hygiene, and recognizing recurrence signs is crucial, alongside ensuring continued access to healthcare services despite logistical challenges. These measures aim to achieve optimal outcomes in managing keratitis and preserving vision in resource-limited settings.

Prevention and control of keratitis in Sub-Saharan Africa

Focus on promoting eye hygiene, improving access to clean water and sanitation in the rural areas, advocating safe contact lens practices in the urban areas, protecting against eye trauma, ensuring early detection and treatment, integrating immunization programs, strengthening eye care services, and conducting research for targeted prevention strategies. These efforts aim to reduce keratitis incidence, minimize vision impairment, and enhance overall eye health outcomes in the region despite resource challenges.

Patient case 

A 28-year-old female farmer from rural Senegal, presented with severe pain, redness, and blurred vision in her right eye after getting dirt in it while working in the fields. Examination revealed marked conjunctival redness, a central ulcer, and reduced visual acuity. She was diagnosed with bacterial keratitis likely due to soil

pathogens. Treatment included topical antibiotics and cycloplegic drops. Despite proper management and follow-up, her condition subsequently led to corneal opacity. This case underscores the challenges and successful management of keratitis in Sub-Saharan Africa, emphasizing early diagnosis, appropriate treatment, and access to healthcare resources.

1. Burton MJ, Pithuwa J, Okello E, Afwamba I, Onyango JJ, Oates F, Chevallier C, Hall AB. Microbial keratitis in East Africa: why are the outcomes so poor? Ophthalmic Epidemiol. 2011 Aug;18(4):158-63. doi: 10.3109/09286586.2011.595041. PMID: 21780874; PMCID: PMC3670402.
2. Erik Schaftenaar, Eric C. M. van Gorp, Christina Meenken, Albert D. M. E. Osterhaus, Lies Remeijer, Helen E. Struthers, James A. McIntyre,  Seerp Baarsma, Georges M. G. M. Verjans, Remco P. H. Peters Ocular infections in sub-Saharan Africa in the context of high HIV prevalence. Tropical Medicine & International Health Volume 19, Issue 9 p. 1003-1014

3. Tobi F Somerville; Shaffi Mdala; Thokozani Zungu; Moira Gandiwa; Rose Herbert; Dean Everett; Caroline E Corless; Nicholas A V Beare; Timothy Neal; Malcolm J Horsburgh et al. Microbial keratitis in Southern Malawi: a microbiological pilot study. BMJ Open Ophthalmology2024-04 | Journal article http://orcid.org/0009-0004-5662-5138
4. Report of the 2030 targets on effective coverage of eye care. Geneva: World Health Organization; 2022. Licence: CC BY-NC-SA 3.0 IGO. Cataloguing-in-Publication (CIP) data. CIP data are available at http://apps.who.int/iris. Retrieved 2024-08-06
5. Srinivasan M, Mascarenhas J, Rajaraman R, et al. Corticosteroids for Bacterial Keratitis: The Steroids for Corneal Ulcers Trial (SCUT). Arch Ophthalmol. 2012;130(2):143–150. doi:10.1001/archophthalmol.2011.315