December 2008 no white pages.indd Contact Lens Induced Corneal Ulcer Management in a Tertiary Eye Unit in Oman - A descriptive study Rikin Shah,1 Manali Shah,1 *Rajiv Khandekar,2 Abdulatif Al-Raisi1 SULTAN QABOOS UNIVERSITY MEDICAL JOURNAL NOVEMBER 2008, VOLUME 8, ISSUE 3, P. 283-290 SULTAN QABOOS UNIVERSITY© SUBMITTED - 23RDSEPTEMBER 2008 ACCEPTED - 2TH JUNE 2008 وحدة في عالجها مت والتي الالصقة العدسات عن الناجتة قرحة القرنية دراسة وصفية - عمان في للعني املستوى الثالث الرئيسي اللطيف عبد راجيف خانديكار، شاه، مانالي شاه، ريكني ــات الالصقة، عن العدس الناجت القرنية بالتهاب أصيبوا مرضى حالة هنا ندرج عمان. في أولوية ذات ــكلة مش القرنية أمراض امللخص: الهدف: تعتبر بفحص العيون أطباء قام .2006 – 2005 في سنتي الدراسة عمان. ألطريقة: أجريت هذه في النهضة وحدة العيون مبستشفى والذين ادخلوا في اتبر إلى الالصقة والعدسات القرنية السحائج من أرسلت عينات سنيلني. طُ طَّ مبُخَ اإلبصار حدة فحص كما يّ احليوي. قِّ الشِّ بَاحِ ِصْ امل رُ هَ مبِجْ العني عند والبصر القرنية فحص مت عالجهم فيها. مت حيث ــفى املستش ــديد الش بالتهاب القرنية املصابني املرضى ادخل ــية. احلساس وفحص الزرع ألجراء و37 15 ذكرا (ل 52 عينا فحص النتائج: مت الثقة. فترات %95 من ال و والنسب األعداد مت حساب أسابيع. ستة املستشفى وبعد من املرضى اخراج حصول من 24 ساعة خالل (25%) فقط 13 مريضا الطبيب راجع 20 – 30 سنة. بني املرضى ثلثي أعمار كانت القرنية. بتقرحات املصابني من أنثى) وجدت ≥5 ملم. لديهم القرحة حجم كان (11.5%) ــى 6 مرض و مركزية بتقرحات مصابا (33%) 17 مريضا ــاك هن كان ــديد. الش القرنية ــاب الته 26 مريضا بعده. (9.6%) و5 عيون العالج قبل (23.1%) 12 عينا في قانوني) (عمى 60/6 اقل من كان البصر .(55.8%) 29 مريضا ــي ف ــة الزائِفَ بصرية. إعاقات الالصقة ــات عن العدس الناجتة ــديدة الش القرنية التهابات ــبب اخلالصة: تس بهم. وفقد االتصال ــفى املستش يراجعوا ــم ل (50%) . القرنية التقرحات عالج أهمية التأكيد على ولهذا يجب الرؤية يحسن أن العالج كما اجليد أساسيان. والتسجيل الوقاية االنكسار. خطأ من العمى، الوقاية القرنية، التهاب العمى القرني، الصقة، الكلمات: عدسات مفتاح 1Department of Ophthalmology, Al Nahdha Hospital, Ministry of Health, Muscat, Oman; 2Eye & Ear Health Care, Department of Control of Non- Communicable Disease, Directorate General Health Affairs, Ministry of Health, Oman *To whom correspondence should be addressed. Email: rajshpp@omantel.net.om ABSTRACT Objectives: The corneal disease is a priority problem in Oman. We present patients with contact lens (CL) induced severe keratitis, admitted in the corneal unit of Al Nahdha Hospital in Oman. Methods: The study was conducted in 2005-2006. Ophthalmologists examined the eyes using slit lamp bio-microscope. Visual acuity was noted using Snellen’s distance vision chart. Specimens of corneal scraping and CLs were sent for culture and sensitivity tests. Patients with severe keratitis were admitted and treated with medicines. Corneal and visual statuses were noted at the time of discharge from hospital and after six weeks. Numbers, percentages and their 95% confidence intervals were calculated. Pre- and post-treatment vision were compared using a scattergram. Results: The 52 eyes of 5 males and 37 female patients with corneal ulcers were examined. Thirty-two patients were between 20 to 30 years of age. Only 3 (25%) patients had visited an ophthalmologist within 24 hours of developing severe keratitis. Seventeen (33%) had central ulcers and six (.5%) had ulcer ≥5 mm in size. Pseudomonas was found in 29 (55.8%) of CL and corneal material scraped from the eyes of 5 (28.8%) patients. Vision was <6/60 (legally blind) in 2 (23.%) eyes before and in five (9.6%) eyes after treatment. Twenty-six (50%) patients were lost to follow up. Conclusion: CL related severe keratitis causes visual disabilities. Prevention and proper records are essential. Treatment improves vision and hence facilities for management should be strengthened. Key words: Contact lens; Corneal blindness, Keratitis; Prevention of blindness; Refractive error. C L I N I C A L A N D B A S I C R E S E A R C H Advances in Knowledge • CL induced keratitis is not included in the World Health Organisation’s Vision 2020 initiative to eliminate all causes of avoidable blindness by 2020. • The CL from an eye with keratitis should be sent to the laboratory in order to isolate the organisms. • Proper and timely management can reduce long term visual disabilities in patients with corneal ulcer due to R I K I N S H A H , M A N A L I S H A H , R A J I V K H A N D E K A R , A B D U L AT I F A L - R A I S I 284 BACTERIAL KERATITIS, ALTHOUGH RARE, IS potentially the most devastating complication of contact lens (CL) wear. The occurrence is more common in soft lens wearers and extended wear of CLs increases the incidence 10 to 15 fold.1 The caus- es of severe keratitis could be: 1. low knowledge and skills among CL providers; 2. poor quality of the prod- uct and/or 3. misuse of lenses by the user. Whatever the cause, the sufferer is certainly the cornea and the patient. Prompt treatment is essential and, even after proper treatment, sequelae may compromise the qual- ity of vision. Conflicting reports suggest trends both of rising and declining incidence of CL induced keratitis. 2, 3 The popularity of coloured CLs has increased among younger generations in recent years. Carelessness and abuse of CL wear could result in catastrophic blind- ness if proper steps are not taken; hence, the Ameri- can Academy of Optometry has stressed the need to impart knowledge both about the advantages of CL system and about the risks if the care of CLs is ne- glected. 4 In Oman, CL practice is the domain of private sec- tor opticians and ophthalmologists. The National Eye Health Care Committee recently introduced a pro- gramme approach to minimise adverse events related to CL wear. 5 We did not find any literature on CL related com- plications in Middle Eastern countries. In Oman, like other Gulf countries, the climate is not conducive to sustained and healthy tear film and, at the same time, the use of the CLs is on the increase. Hence, we re- viewed the cases of CL induced severe keratitis that were admitted in the cornea unit of Al Nahdha Hos- pital, a tertiary hospital in Oman. The profile, clinical presentation, modalities of treatment and visual status are here presented. M E T H O D S This study was a retrospective descriptive study in which ophthalmological hospital records were re- viewed. It was approved by the ethical and research committee of Al-Nahdha Hospital. In this series, we included patients that were admitted in the cornea unit of the hospital between January 2005 and Decem- ber 2006. Three senior ophthalmologists of the cornea unit were our investigators. The computerised case records of these patients were used to generate relevant information. An agreed protocol is used by ophthalmologists of the cornea unit in all cases of corneal ulcer. The history included duration of using the present CLs, initial symptoms, treatment before admission, sharing of CLs and CL hygiene practices. Eyes with acute onset of keratitis, involving the visual axis or with hypopyon, were con- sidered to suffer from sight threatening condition and such patients were admitted into the hospital. The visual acuity of each eye of the patient was noted using Snellen’s illiterate ‘E’ chart, held at a six metre distance from the patient. If the patient could not open the eye due to blepharospasm or photopho- bia, one drop of 0.4% oxybuprocaine hydrochloride (minims) was instilled. If the person could not identify the ‘E’ in the top line, the test was repeated at a three metre distance. The projection of light and percep- tion of light rays were tested in all four quadrants for those who could not be tested for visual acuity even at 3 metre distance. The fluorescein minims were used and the corneal ulcer was observed using a slit lamp biomicroscope. The size of the ulcer was measured us- ing a grid. The ulcer was graded as ‘less than 3 mm’, ‘3 to 5 mm’ and ‘more than 5 mm in size’. The location CL wear. • Pseudomonas organisms were mainly responsible for corneal ulcer in our patients. Corneal ulcer due to acanthomoeba was not found in our series. Application to Patient Care • Materials should be collected from corneal scraping and CLs for culture and sensitivity tests before starting antibiotic treatment. • Until the report of culture and sensitivity is available, one should assume that keratitis is due to pseu- domonas and antibiotics should be given accordingly. • Proper records of the extent of keratitis and visual acuity are useful to evaluate the response to treatment. C O N TA C T L E N S I N D U C E D C O R N E A L U L C E R M A N A G E D I N A TE R T I A R Y E Y E U N I T I N O M A N - A D E S C R I P T I V E S T U D Y 285 of the ulcer was designated ‘central’ if it covered the pupil, ‘para-central’ if it partly covered the pupil or ‘pe- ripheral’ if the central cornea that covers the pupil was not affected. The presence of hypopyon was grouped according to its level in the anterior chamber, the cat- egories being: <1/3, between 1/3 and ½ and more than half of the anterior chamber. The CLs were sent to the laboratory for culture and sensitivity tests. Minims of oxybuprocaine hydrochlo- ride 0.4% were used to anaesthetise the cornea. The culture specimen was obtained from the edge and the bed of the ulcer. The material was inoculated on cul- ture media (blood agar, chocolate agar, Sabraud’s agar, MacConkey agar, brain-heart- infusion broth); gram and potassium hydroxide staining was carried out and subsequently culture and sensitivity tests were per- formed. The patients with severe keratitis were treated with wide spectrum antibiotics. In the presence of hypopyon, 1% atropine eye drop was instilled for cy- cloplegia and oral acetazolamide (250 mg four times a day) was given if the intraocular pressure was raised. The antibiotic was changed subsequently according to the culture and sensitivity report. When staining was negative and the ulcer was healed, the person was dis- charged. Information on the status of vision and the cornea were noted before sending patients home and during the follow up at one and six weeks. The eye ex- amination methods were similar on admission and fol- low up. The patient was advised not to use CLs for the next 3 to 6 months depending upon size and severity of the ulcer. Health education was given for the care of CLs. All details were recorded in computerised case records. A pre-tested data collection form was used to gather information from the case records. Personal logbooks of corneal specialists of the unit were also referred to. The data was then entered into a Micro- soft XL spreadsheet. It was converted to the Statistical Package for Social Studies (SPSS-12) and a univariate parametric type of analysis was carried out to calcu- late frequencies and percentage proportions. For sta- tistical validation, we used 95% confidence intervals (95% CI) of percentage proportions. All patients with severe keratitis were treated free of cost. Their identities were de-linked from the results at the time of analysis. The authors presented the out- comes of this study in a national ophthalmic meeting to increase the awareness and knowledge among the CL practitioners and ophthalmologists of Oman. R E S U L T S Fifty-two patients had corneal ulcers in their eyes (18 in the right eye, 27 in the left eye and 7 in both eyes). The profile of the patients with keratitis is shown in Table 1. Thirteen (25%) patients had approached a cor- nea clinic within 24 hours and 17 (32.7%) patients had used antibiotics before visiting our institution. Twen- Table 1: Profile of patients with contact lens induced severe keratitis Patients with Keratitis # % 95% Confidence Interval Gender Male Female 15 37 28.8 71.2 6.6- 32.0 69.2 - 73.2 Age-group 10 to 20 years 21 to 30 years 31 to 40 years 41 years and more 10 32 6 4 19.2 61.5 11.5 7.7 8.8- 22.6 2.2- 63.8 8.0- 15.0 4.1- 11.3 Reference pattern Emergency in morning Emergency in evening Primary health centres Regional hospitals Private ophthalmologists 25 13 3 6 5 48.1 25.0 5.8 11.5 9.6 4.4- 50.8 7.7- 28.3 1.1- 9.5 8.0- 15.0 6.0 - 13.2 Interval between keratitis and ophthalmic visit <24 hours 24 to 48 hours <1 week 1 to 2 week > 2 week 13 11 11 2 5 25.0 21.2 21.2 3.8 9.6 7.7 - 28.3 17.9 - 24.5 17.9 - 24.5 1.1- 7.5 6.0- 13.2 Total 52 100 R I K I N S H A H , M A N A L I S H A H , R A J I V K H A N D E K A R , A B D U L AT I F A L - R A I S I 286 ty-six (50%) patients had not used antibiotics, while in nine (17.3%) patients, this information was not avail- able. In our institute during the same period, 177 pa- tients with corneal ulcers were admitted. The propor- tion of CL induced corneal ulcer to the total cases of corneal ulcer was 29.4%. Daily wear is common and extended wear soft lenses and disposable CLs are extensively used in Oman compared to hard CLs which are rarely used. Therefore, we can safely assume that all the patients with keratitis in our series wear soft lenses. The salient features of the corneal ulcers in our se- ries are given in Table 2. One fourth of patients had pe- ripheral ulcers. Only 35 (67.3%) patients had brought their CLs with them to be tested for bacterial growth and antibiotic sensitivity. Thirty-seven (71.2%) patients were treated with fortified gentamycin (14mg/ml) and fortified cefuroxime (50mg /ml) eye drops, while in twelve (23%) patients ofloxacilline eye drops were used. Three (6%) patients were treated with ofloxacil- line and other fortified drugs (fortified gentamycin/ fortified amikacin). Fourteen (30%) patients were ad- mitted for three days, nineteen (36.5%) patients were admitted for one week and nine (17.3%) patients were in the hospital for two weeks. Six (11.5%) patients left hospital against medical advice before completing the treatment. Visual acuity was tested in the eye with keratitis on admission and at the time of discharge. Twelve (23%) eyes of 52 patients with severe keratitis had visual acu- ity of <6/60 (legally blind) at the time of admission. In contrast, only five (9.6%) eyes of 52 patients had visual acuity of less than 6/60 following the management of severe keratitis. A percentage scattergram comparing pre- and post-treatment vision is given in Table 3. In one eye only, the vision deteriorated following treat- ment. After leaving the hospital, 13 (25%) of patients did not return for follow up. Only 16 (30.7%) patients had been followed up after 3 months. Twenty-eight (53.8%) patients were advised to continue ofloxacillin eye drops even after leaving the hospital. Another 18 (34.6%) patients were given the gentamycin eye drops in addition to the ofloxacillin eye drops. Twenty-one (40.4%) patients were also given lubricant eye drops. Topical steroids were used in treatment of only 8 (15.4%) patients. The status of the corneas following treatment is given in Table 4. Nearly half of the pa- tients treated for severe keratitis were advised to use spectacles to correct their refractive error. Corneal ulcer Number of eyes Percentage 95% Confidence Interval Location Central Paracentral Peripheral 17 21 14 32.7 40.4 26.9 29.6 - 35.8 37.5 -43.3 23.7- 30.1 Size <3 mm 3 to 5 mm 6 mm and more 39 6 6 75.0 11.5 11.5 73.1- 76.9 8.0 -15.0 8.0- 15.0 Hypopyon Absent 1/3 to ½ of anterior chamber >1/2 of anterior chamber 42 9 1 80.8 17.3 1.9 79.1- 82.5 13.9- 20.7 0.0- 5.6 Culture of corneal scrapping Gram staining No growth Gram +ve cocci Gram – ve bacilli Not done / Missing Culture No growth Pseudomonas Missing 35 1 4 12 28 15 9 67.3 1.9 7.7 23 53.8 28.8 17.3 65.1- 69.5 -1.8- 5.6 4.1- 11.3 19.7- 26.3 51.2- 56.4 25.6- 32.0 13.9- 20.7 Culture of contact lens Pseudomonas Other No growth Not done 29 4 2 17 55.8 7.7 3.8 32.7 53.3- 58.3 4.1- 11.3 0.1- 7.5 29.6- 35.8 Table 2: Characteristics of ulcers in eyes of patients with contact lens induced severe keratitis C O N TA C T L E N S I N D U C E D C O R N E A L U L C E R M A N A G E D I N A TE R T I A R Y E Y E U N I T I N O M A N - A D E S C R I P T I V E S T U D Y 287 D I S C U S S I O N Our study highlights the importance of reviewing CL induced severe keratitis. Eighty percent of our patients were less than 30 years of age. It is known that even after successful treatment of severe keratitis, corneal opacities will be unavoidable thus causing visual im- pairment, which could be a social and economic dis- aster at such a young age. Fortunately, vision improved in all except in one case in our study. Thus, prompt and standard treatment of severe keratitis is crucial to prevent visual disabilities. Pseudomonas was the main organism found in CLs used in the eyes of patients with corneal ulcer in our study. Surprisingly, we did not come across keratitis due to acanthomoeba, but the fact that nearly 50% of the sample were ‘without growth’ after laboratory tests in our study is worthy to note. The ulcers were mainly in the visual axis and were of < 3 mm diameter. The main characteristics of the patients in our series were: a majority of female patients; age range from 20 to 30 years; coming for treatment in the early hours of the day 24 hours after symptoms appeared. Unfortunately, a large number of cases were lost to followup and therefore we could not compare visual recovery in nearly 48% of cases. Loss of data and pa- tients in follow up visits are known limitations of a study based on data review.6 Therefore, correlation of visual impairment to the categories like causative or- ganisms or age group could not be attempted. Further studies of a prospective nature with a larger sample are recommended. To the best of our knowledge, this study was the first of its kind in the Gulf countries. Since complication due to CL wear is a problem of the young generation, the loss of DALYS (disability adjusted life years) will be high. In spite of treatment, it could cause unilateral blindness and/or low vision. In these circumstances, the outcomes of our study would be important not only to Oman but also to many other countries having a similar CL delivery system. Oman has prioritised corneal diseases within its Vision 2020 initiative.7 Corneal complications con- tributed to 14% of blindness in the population aged >40 years in 2005. The majority of them were due to corneal complications of trachoma. Trachomatous trichaisis has declined in the last decade.8, 9 However, the cornea is now at a higher risk due to the increased use of CLs in Oman. The scope for using CLs is large in Oman since the prevalence of myopia in 16 to 17 years old school children is as high as 12% and the compli- Initial Visual Acuity 6/6 (7) 6/9 (0) 6/12 (5) 6/18 (3) 6/24 (4) 6/36 (3) 6/60 (8) <6/60 to 3/60 (7) <6/60 - PLPR+ (5) Missing (10) Total (52) Follow up Visual acuity ‚ 6/6 1.9 3.8 5.8 3.8 5.8 11 6/9 1.9 1.9 1.9 1.9 1.9 5 6/12 1.9 1.9 1.9 3 6/18 1.9 1 6/24 3.8 2 6/36 1.9 1 6/60 1.9 1.9 2 <6/60 to 3/60 1.9 2 <3/60 to PLPR + 1.9 1.9 1 Not known 5.7 1.9 3.8 3.8 3.8 5.8 5.8 5.8 5.8 3.8 24 Initial visual acuity ‡ <3/60 -PLPR + <6/60 to 3/60 6/60 6/36 6/24 6/18 6/12 6/9 6/6 Missing PL = Perception of light; PR = Projection of light Table 3: Percentage Scatter gram: Initial and final visual acuity in eyes treated for contact lens induced severe keratitis R I K I N S H A H , M A N A L I S H A H , R A J I V K H A N D E K A R , A B D U L AT I F A L - R A I S I 288 ance of spectacle wear is only 70%.10, 11 In industrialized countries, it has also been noted that the proportion of severe keratitis due to CL wear has increased the total number of cases of corneal ulcer needing admission by up to 50%.12 Thus, awareness campaigns targeting these potential patients could use the information of our study to warn them of the consequences of abus- ing CLs. CL induced keratitis was 30% of total admissions in our institute. This rate was close to the 33% reported by Keay et al.13 Pseudomonas was the main organism responsible for severe keratitis. Many other research- ers have also noted these organisms as the main culprit of keratitis.14, 15 We found bacteria both in the sample collected from the corneal ulcer and from the CL. Mela et al., in their study, demonstrated the importance of sending both the material from corneal scraping and from the CLs for culture.16 Hence, it is important to in- form the family physician or optician referring the case to ensure that the patient is sent with the CLs when the case is referred for admission and care. We found four cases with gram negative bacilli and one case of gram positive cocci. But, we could not carry out culture and sensitivity tests for them as we could not culture them on artificial media and test for sensitivity. Inoue et al. noted gram positive and gram negative bacteria and fungi and acanthamoeba in their specimen. 17 A study in Belgium, reported pseudomonas as the main culprit of CL induced severe keratitis. 18 Only 25% of our patients had consulted an oph- thalmologist within 24 hours of development of symptoms showing that further strengthening of the reference system is therefore urgently needed. Opti- cians and family physicians should be educated about the problems related to CL use and need for prompt treatment by experts to avoid sight-threatening com- plications. Under the guidance of cornea specialists, a standard management protocol should be prepared to be followed by all ophthalmologists and CL practition- ers. A large number of samples with ‘no growth’ after laboratory tests could be due to the use of antibiot- ics before the collection of the sample. The referring practitioners should be aware of the need to collect the sample both from the cornea and the lenses before commencing antibiotic treatment. Central corneal ulcers and peripheral ulcers can be due to different causes and organisms.19 In our study also, we noted that central ulcers of more than 5 mm in size were due to pseudomonas organisms. However, gram negative organisms were noted in samples from both paracen- tral and peripheral keratitis. Twenty eight (53.8%) of laboratory tests reported ‘no growth’, hence associat- ing the site of ulcer to the type of organisms should be done with caution in our study. We could avoid perforation and its sequelae by good treatment; however, the vision remained < 6/60 due to corneal opacities in five (19%) patients. Visual acuity following successful treatment of CL induced corneal ulcer in another study was < 20/200 in two out of nine cases in a group of myopic persons using soft CLs. 20 Adam et al. studied complications in persons using cosmetic CLs and found that one out of six eyes were blind after treatment. 21 A study with a larger sample is recommended to confirm these observa- tions. A limitation of our study is that patients presenting with mild corneal ulcers that were treated in clinics and not admitted into hospital were not included in Number Percentage Location of opacity Central Paracentral Peripheral No opacity Missing 11 11 8 7 15 21.2 21.2 15.4 13.5 28.8 Treatment of sequel Keratoplasty No keratoplasty Missing information 4 24 24 7.8 46.1 46.1 Advice for correcting refractive error To continue contact lens Use of spectacles Undergone refractive surgery Missing 4 12 1 1 7.7 25 1.9 1.9 Table 4: Corneal status and suggested correction following treatment of contact lens induced severe keratitis. C O N TA C T L E N S I N D U C E D C O R N E A L U L C E R M A N A G E D I N A TE R T I A R Y E Y E U N I T I N O M A N - A D E S C R I P T I V E S T U D Y 289 our study. Although computerised case records were useful, a switch from manual to computer records co- incided with our study period. This could have affected our study as the learning curve of the ophthalmologists in using the computerised system may have resulted in incomplete data. Our study was retrospective in na- ture; hence, the attrition of cases following discharge and loss of data were inherent limitations.6 Thus, the results of our study are limited to CL induced severe keratitis that needed treatment under supervision. Therefore, any attempt to extrapolate the result of our study should be undertaken with due caution. C O N C L U S I O N Our study suggests that vision improves following prompt and standard treatment of CL induced severe keratitis. Prompt referral, standard management, reg- ular follow up and proper case records are essential. In view of the high rate of corneal ulcers in CL wearers, CL dispensing practice in Oman should be monitored. Ophthalmologists, CL providers and CL users should work jointly to solve this issue. A C K N OW L E D G ME N TS We thank the staff of the Ophthalmology Department at Al Nahdha Hospital for all their assistance and care of the patients. We also thank the staff of the health record section there. The hospital administrators gave their permission for this study and we appreciate their cooperation. We thank the patients and their relatives who in spite of their suffering gave their consent to use the information for improving eye care. We are grate- ful for their cooperation and support. The authors did not have any conflicts of interest (financial or other) in conducting this study. The subject was presented in International Oph- thalmology Conference in February 2007 in Muscat, Oman. R E F E R E N C E S 1. Albert DM, Jakobiec FA. Contact Lens. In: Principles and Practice of Ophthalmology, Ch. 6, Vol.6 2nd ed. Philadelphia: WB Saunders Company, 2004. p. 5368. 2. Verhelst D, Koppen C, Van Looveren J, Meheus A, Tas- signon MJ; the Belgian Keratitis Study Group. 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