|LETTER TO THE EDITOR
|Year : 2019 | Volume
| Issue : 9 | Page : 1506-1507
Commentary: Clinical presentations and comparative outcomes of primary versus deferred intraocular lens explantation in delayed-onset endophthalmitis
Department of Ophthalmology, National University Health System, Singapore
|Date of Web Publication||22-Aug-2019|
Dr. Lingam Gopal
1E, Kent Ridge Road, NUHS
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Gopal L. Commentary: Clinical presentations and comparative outcomes of primary versus deferred intraocular lens explantation in delayed-onset endophthalmitis. Indian J Ophthalmol 2019;67:1506-7
While the term endophthalmitis is reasonably clear in its connotation, the term 'delayed onset' is not as clear due to several reasons.
- The delay by definition relates to the interval between the surgical intervention and the clinical manifestation of endophthalmitis. This assumes that the entry of organisms has taken place at the time of surgery but the delay in clinical manifestations is due to several reasons including low virulence of the organism, slow growing organism, sequestered nature of organism, low organismal load, good immunity, inadequately treated contamination and other as yet unknown factors
- The delay could also be due to organismal invasion occurring later as in blebitis leading to endophthalmitis, suture removal leading to endophthalmitis, etc., In this situation, the endophthalmitis should be termed acute since the inoculation of the organism has occurred more recently
- Further confusion is caused by the timing when the clinician has decided to call the case as infective endophthalmitis. Many cases of mild post-operative inflammation may be treated as non-infective and may actually respond only to steroids but keep recurring and progressively become more severe. It is at that stage that the clinician would harbour the idea of infection and perhaps for the first time subject the case to tap and jab. Should one call this delayed endophthalmitis, considering that there was inflammation in the immediate post-operative period?
The presence of IOL adds a complexity to the overall management of intra ocular infection. This can be due to the propensity of exudates to cover the IOL and capsular bag – causing a physical impediment to performance of adequate surgery and clearance of the purulent material. The complexity is also due to the relative inaccessibility of the space between IOL and capsular bag to the drugs being administered.
In this issue of IJO Dave et al. discuss the outcomes of management of 'delayed onset endophthalmitis' by vitrectomy. They compare a group where the IOL was removed at the first instance, with another group where an attempt was made to preserve the IOL but had to be removed later on. The cases included not only post cataract surgery infections but also infections occurring after trauma, keratoplasty, trabeculectomy and even endogenous endophthalmitis (as long as the eye is pseudophakic). The study does not include cases where IOL explanation was not needed in the control of infections (with or without vitrectomy).
The study showed that removal of IOL at primary instance reduces the number of repeat interventions needed to control the infection compared to deferred group. The limitations of the study have been enumerated by the authors in the discussion.
- The cases included post cataract surgery, post other intra ocular surgeries, post-traumatic and endogenous in origin.
Hence the capsular bag and IOL may be playing a primary role in the perpetuation of infection as in (sequestered post cataract surgery endophthalmitis) or just be involved in the overall intra ocular infection
However, it is possible that once the organisms find their way into the capsular bag (even in other than post cataract surgery situation), they may be that much more difficult to eradicate irrespective of whether the bugs were implanted with the IOL or found this crevice later on as a safe haven.
- There were 37 microbiologically positive cases out of the 77 in this study. While dealing with 'delayed/chronic endophthalmitis', the causative organism plays an important role in the overall presentation and response to treatment. For example: It has been the experience of most surgeons that fungal infections are most difficult to eradicate and early removal of IOL helps in this process. Hence the kind of organism that caused the infection could be an important confounder. This factor could not be brought out in this study due to several reasons (1) Fewer number of cases with culture positivity (2) Only univariate analysis was done and logistic regression was not done
- Considering the fact that cases that were cured despite retention of IOL have been excluded from this study, an important piece of information is unfortunately missing. i.e., Overall, in pseudophakic eyes, what is the incidence of cure (of endophthalmitis of any origin) without sacrifice of IOL?
- It would also have been useful if one were to do a sub group analysis of the cases of post cataract surgery endophthalmitis alone- just to test the hypothesis whether the capsular bag serves as a reservoir of organisms (that are especially difficult to eradicate) only if they were implanted with IOL or can organisms find their way into this relatively inaccessible space long after cataract surgery and serve as a nidus for perpetuation of infection.
In conclusion, the article by Dave et al. raises an important management issue of IOL sacrifice versus retention in managing pseudophakic endophthalmitis. Despite the limitations of the study, one important message emanates i.e. when in doubt and if IOL removal is deemed a possible necessity, it is better to remove the IOL earlier than be pushed towards its removal after repeated attempts at IOL salvage have failed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Dave VP, Pathengay A, Sharma S, Govindhari V, Karolia R, Pappuru RR, et al.
Clinical presentations and comparative outcomes of primary versus deferred intraocular lens explantation in delayed-onset endophthalmitis. Indian J Ophthalmol 2019;67:1101-4.
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