Abstract
Background: Infective corneal ulceration is at present the leading cause of ocular morbidity and unilateral
blindness in developing countries and the most common cause of acute blinding corneal problem
requiring treatment. For the past 10 years, it has been the leading cause of admission at Muhimbili
National Hospital. Proper microbial diagnosis and management of infective corneal ulceration requires
culture and sensitivity tests that may not be available in some secondary and tertiary facilities in Tanzania.
Knowledge of local microbial aetiology is therefore necessary for early and effective management to
avoid long term corneal complications and subsequent blindness. The aim of the study was to
determine the common local causative organisms of infective corneal ulceration.
Objective: To identify causative pathogens responsible for infective corneal ulceration at Muhimbili
National Hospital. And to determine the demographic factors of the study population.
Design: Cross sectional study conducted from June 2007 to June 2008.
Setting: Muhimbili National Hospital, Dar-es-Salaam.
Participants: Two hundred and two patients of all age groups with corneal ulceration.
Results: Fourty point one percent of ulcers were bacterial, 36.6.0% were fungal and 14.4% viral. Staphylococcal
species were the commonest bacteria isolated on culture while candida albicans was the
commonest causative fungus. The aetiology of 18 (8.9%) corneal ulcers could not be determined.
Conclusion: Although bacteria are the leading cause of corneal ulceration, the proportion of fungus
as a cause of corneal ulceration has increased to almost equal that of bacteria. Staphylococcal spp,
streptococcal spp and candida albicans were the leading causative organisms. Treatment based on clinical
grounds should target these organisms.
References
Upadhyay MP, Srinivasan M, Whitcher JP.
Managing corneal disease: focus on suppurative
keratitis. Community Eye Health. 2009;22(71):39-41.
Burton J. Corneal blindness: Prevention, treatment,
and rehabilitation. Community Eye Health. 2009;
(71):33-35.
Gonzales CA, Srinivasan M, Whitcher JP, Smolin G.
Incidence of corneal ulceration in Madurai district,
South India. Ophthalmic Epidemiol. 1996;
(3):159-166.
Jeng BH, Gritz DC, Kumar AB, et al. Epidemiology
of ulcerative keratitis in Northern California. Arch
Ophthalmol. 2010; 128(8):1022-1028.
Mafwiri M, Mwakyusa N, Msela G. The pattern of
corneal diseases in Dar-es-Salaam. East Afr. J.
Ophthalmol. 2006; 12:4-7.
Whitcher JP, Srinivasan M, Upadhyay MP. Corneal
blindness: a global perspective. Bull World Health
Organ. 2001; 79(3):214-221.
Leck AK, Thomas PA, Hagan M, et al. Aetiology of
suppurative corneal ulcers in Ghana and south
India, and epidemiology of fungal keratitis. Br J
Ophthalmol. 2002; 86(11):1211-1215.
Sirikul T, Prabriputaloong T, Smathivat A, Chuck
RS, Vongthongsri A. Predisposing factors and etiologic
diagnosis of ulcerative keratitis. Cornea. 2008;
(3):283-287.
Srinivasan M, Gonzales CA, George C, et al. Epidemiology
and aetiological diagnosis of corneal ulceration
in Madurai, south India. Br J Ophthalmol. 1997;
(11):965-971.
Hagan M, Wright E, Newman M, Dolin P, Johnson G.
Causes of suppurative keratitis in Ghana. Br J Ophthalmol.
; 79(11):1024-1028.
Carmichael TR, Wolpert M, Koornhof HJ. Corneal
ulceration at an urban African hospital. Br J
Ophthalmol. 1985; 69(12):920-926.
Upadhyay MP, Karmacharya PC, Koirala S, et al.
Epidemiologic characteristics, predisposing factors,
and etiologic diagnosis of corneal ulceration in
Nepal. Am J Ophthalmol. 1991; 111(1):92-99.
Dunlop AA, Wright ED, Howlader SA, et al. Suppurative
corneal ulceration in Bangladesh. A study
of 142 cases examining the microbiological diagnosis,
clinical and epidemiological features of bacterial
and fungal keratitis. Aust N Z J Ophthalmol.
; 22(2):105-110.
Asbell P, Stenson S. Ulcerative keratitis. Survey of 30
years' laboratory experience. Arch Ophthalmol. 1982;
(1):77-80.
Liesegang TJ, Forster RK. Spectrum of microbial
keratitis in South Florida. Am J Ophthalmol. 1980;
(1):38-47.
Chaudhuri PR, Godfrey B. Treatment of bacterial corneal
ulcers with concentrated antibiotic eye drops. Trans
Ophthalmol Soc U K. 1982; 102 (Pt 1):11-14.
Thomas PA, Leck AK, Myatt M. Characteristic
clinical features as an aid to the diagnosis of suppurative
keratitis caused by filamentous fungi. Br J Ophthalmol.
; 89(12):1554-1558.