|LETTER TO THE EDITOR
|Year : 2020 | Volume
| Issue : 7 | Page : 1509-1510
Comments on: Outer retinal tubulation and inner retinal pseudocysts in a patient with maternally inherited diabetes and deafness evaluated with optical coherence tomography angiogram
Krankenanstalt Rudolfstiftung, Messerli Institute, Vienna, Wien, Austria
|Date of Web Publication||25-Jun-2020|
Prof. Josef Finsterer
Postfach 20, 1180 Vienna, Austria
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Finsterer J. Comments on: Outer retinal tubulation and inner retinal pseudocysts in a patient with maternally inherited diabetes and deafness evaluated with optical coherence tomography angiogram. Indian J Ophthalmol 2020;68:1509-10
|How to cite this URL:|
Finsterer J. Comments on: Outer retinal tubulation and inner retinal pseudocysts in a patient with maternally inherited diabetes and deafness evaluated with optical coherence tomography angiogram. Indian J Ophthalmol [serial online] 2020 [cited 2020 Jul 13];68:1509-10. Available from: http://www.ijo.in/text.asp?2020/68/7/1509/287555
With interest we read the article by Tripathy et al. about a 47-year-old female with hypoacusis, diabetes, and ischemic heart disease attributed to the mtDNA variant m.3243A>G in MT-TL1. Ophthalmologic investigations revealed areas of foveal atrophy and hypoautofluorescence, depression of inner retinal surface, pseudocysts, thinning of the outer retina, outer retinal tabulation, loss of external limiting membrane and thinning of retinal pigment epithelium, and choriocapillaris. Retinal and choreal abnormalities were interpreted as subclinical involvement in the mitochondrial disorder (MID). We witnessed a number of shortcomings in the study which have been stated as follows:
Firstly, no heteroplasmy rates in any affected or non-affected tissue were provided. We should know heteroplasmy rates since they can be helpful to predict the disease trajectory and are required for genetic counselling.
Secondly, the mother of the index patient was not genetically investigated. Since 75% of the mtDNA mutations are maternally inherited, it is conceivable that the culprit variant was transmitted via the maternal line. Phenotypic expression in the mother at variance from that in her daughter is not unusual since the phenotypic expression of an mtDNA variant can be highly heterogeneous between family members. We should be aware if the mother of the index patient also manifested with hypoacusis and diabetes in addition to the cataract.
Thirdly, neither the index patient nor her mother were prospectively investigated for multisystem disease, frequently found in m.3243A>G carriers.
In addition, we should be informed about the cause of ischemic heart disease, that is, whether it was due to coronary heart disease from diabetes or a primary manifestation of the underlying genetic defect, as has been recently demonstrated.
Overall, this interesting case report has a number of shortcomings which need to be addressed before the conclusions drawn can be adopted.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
Tripathy K, Sarma B, Mazumdar S. Outer retinal tubulation and inner retinal pseudocysts in a patient with maternally inherited diabetes and deafness evaluated with optical coherence tomography angiogram. Indian J Ophthalmol 2020;68:250-3.
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