a retrospective chart review was performed for cases of infectious scleritis seen from january 2007 to august 2011 . the diagnostic criteria for a case of infectious scleritis included the presence of single or multiple inflamed anterior scleral nodules or ulcerations , which revealed a causative organism on microbiological culture . microbial cultures were considered significant if growth of the same organism was present on more than one solid medium or if there was a confluent growth on inoculation on one solid medium or if growth of one medium was consistent with direct microscopy findings . data regarding patient demographics , predisposing factors , causative organisms , and clinical features for all 12 patients was extracted . all patients except one were followed up for a period of at least 6 months and , therefore , the treatment and outcome details were analyzed for 11 patients . data was analyzed by the chi - square test using spss version 11.0.1 to determine the prognostic factors . twelve eyes of 12 patients were identified to have culture - positive infectious scleritis . demographic data and clinical features preceding surgical procedures performed included manual small - incision cataract surgery ( 4 ) , pterygium excision ( 1 ) , and trabeculectomy ( 1 ) . none of the patients had a history of fever , joint pain , respiratory illness , skin rashes , etc . , one patient ( case 2 ) had progeria , another had chronic liver disease ( case 6 ) , and 2 patients had diabetes ( case 8 and 10 ) . patients with multifocal scleritis were associated with growth of either gram - negative bacilli ( gnb ) or nocardia on culture an example of which is shown in fig . 2a and b. demographics , clinical features , organisms , management , and outcomes of infectious scleritis ( a ) multifocal scleral abscesses owing to pseudomonas sp . ( b ) healed scleritis with minimal scleral thinning 2 months after treatment with topical fortified antibiotics and dexamethasone ( case 11 ) ( a ) nocardia asteroides : gram stain showing filamentous forms fragmented into bacillary and coccoid forms ( magnification = 1000 ) . ( b ) nocardia asteroides : orange coloured , centrally heaped , dry colony all patients received topical antimicrobials based on the culture and sensitivity report . seven patients were also treated with topical steroids due to severe intra - ocular inflammation . in addition to medical treatment , 5 patients underwent various surgical procedures in an attempt to decrease the load of infective organism or to preserve the globe as shown in table 1 and fig . of these , only 2 patients had a good final visual acuity ( better than 6/18 ) on the last follow - up visit . six months after corneo - scleral patch graft following infectious scleritis post - cataract surgery ( case 8) we determined the prognostic factors of infectious scleritis using the chi - square test . a poor visual acuity at presentation ( less than counting fingers at 1 m ) usually resulted in a worse visual outcome ( p = 0.005 ) . the causes of poor visual acuity at last follow - up include corneal scarring following keratitis ( 1 ) , failed corneal graft ( 1 ) , secondary angle closure glaucoma and optic atrophy ( 1 ) , choroidal detachment ( 1 ) , and endophthalmitis ( 5 ) . the visual outcome was not dependant on any particular organism ( p = 0.099 ) or the presence of multifocal abscesses ( p = 0.209 ) . the addition of surgical intervention did not result in a significantly better visual outcome than medical management alone ( p = 0.209 ) , but resulted in a higher rate of globe preservation ( p = 0.045 ) . a clinical suspicion of infectious scleritis in all cases of scleral inflammation following trauma has been emphasized previously . however , in our series , 4 cases were preceded by cataract surgery and only 1 by pterygium surgery . another case series of indian eyes also showed maximum number of their cases had cataract surgery prior to an episode of infectious scleritis . this may be due to the large number of scleral - tunnel small incision cataract surgeries performed in india as compared to clear corneal phacoemulsification performed in developed countries . pseudomonas aeruginosa is the leading cause of microbial scleritis in reported literature . in our series , 33.33% had gnb , 25% had nocardia , and 25% had fungal infection . one of the fungi was identified to be rhodotorula spp , which we have reported elsewhere . in cases of scleritis following trauma where infection is suspected but routine microbial culture is negative , polymerase chain reaction tests may be used to confirm the diagnosis . if these tests are also negative , the possible diagnosis of surgically induced necrotizing scleritis ( sins ) should be considered . sins is a believed to be a delayed - type hypersensitivity response to any form of surgical trauma . up to 90% of patients who develop sins may have an undiagnosed systemic vasculitis and , therefore , a detailed systemic investigation is warranted . this is often seen as late as 9 months after the surgical intervention and , after ruling out an infectious cause , requires treatment with intensive systemic immunosuppression . when infectious scleritis occurs long after surgery , it has been hypothesized to be due to an underlying sins with secondary microbial infection , which can make diagnosis and treatment difficult . these patients may benefit from a systemic evaluation to rule out an autoimmune vasculitis , which will require appropriate management . some presented with scleritis and developed secondary intraocular spread , which has been described in other reports . others had scleritis , uveitis , and endophthalmitis at presentation ( e.g. , case 7 where the sclera in the area of the bleb was necrotic with vitreous inflammation ) . the wide use of anti - metabolites at the time of trabeculectomy increases risk of scleral melt and inflammation , which may have resulted in secondary infection and endophthalmitis . pseudomonas is most often associated with this presentation , which has been attributed to an intra - scleral dissemination facilitated by its proteolytic products and motility . our series had 6 cases of multifocal scleral abscesses , 3 of which were due to p. aeruginosa , 2 due to nocardia , and 1 due to klebsiella sp . a review of past literature suggests that multifocal scleritis can be caused by several organisms and may be related to factors such as the load of infection , rather than specific organisms . the visual acuity at presentation is the most important prognostic factor determining the final visual acuity , and this has been seen in other studies . this suggests that early diagnosis should help preserve the patient 's remaining vision if effective treatment is initiated . there is a lot of discrepancy among researchers regarding the effect of surgical debridement on the outcome of infectious scleritis . a large series showed that despite adjuvant surgery in 46 of 56 eyes , approximately 50% lost functional vision . however , unlike other studies , we did not find any difference in the final vision between the medically and surgically treated groups . in conclusion , manual small incision cataract surgery is a common predisposing factor to infectious scleritis in developing countries . the visual acuity at presentation is the most important prognostic factor determining the final visual outcome . aggressive surgical intervention improves the chance of globe preservation but does not improve the visual outcome .
in this retrospective case series , we studied the predisposing factors , causative organisms , clinical spectrum , and outcomes of 12 cases of culture - proven infectious scleritis . 
 nine of 12 patients had a history of preceding trauma ( surgical or accidental ) . 
 past surgical history included small - incision cataract surgery ( 4 ) , pterygium surgery ( 1 ) , and trabeculectomy ( 1 ) . 
 six patients had multifocal scleral abscesses due to pseudomonas , klebsiella , or nocardia . only 2 patients retained useful vision ( > 6/18 ) . a poor visual acuity at presentation usually resulted in a worse visual outcome ( p = 0.005 ) . 
 four eyes developed phthisis . 
 the addition of surgical intervention did not result in a significantly better visual outcome than medical management alone ( p = 0.209 ) , but resulted in a higher globe preservation rate ( p = 0.045 ) . 
 therefore , we concluded that infection must be ruled out in cases of scleritis with preceding history of trauma , and aggressive surgical intervention improves the anatomical outcome but does not change the visual outcome .