Comments on: Ocular surface characterization after allogeneic stem cell transplantation: A prospective study in a referral center.

Dear Editor,

We commend the authors' work in their study on ocular surface characterization after allogeneic hematopoietic stem cell transplant (allo-HSCT).[1] We wish to highlight a few points based on our experience.[234]

The authors have not clarified the diagnostic criteria used to diagnose ocular GVHD (oGVHD) in their methodology and perhaps used the Spanish NIH diagnostic criteria (which has not been referenced) which, they mentioned in the discussion. Currently the 2 most widely acknowledged diagnostic criteria for oGVHD are the National Institute of Health Consensus Conference criteria (NIH-CC)[5] and International Chronic oGVHD (ICCGVHD) consensus group diagnostic criteria.[6] In chronic systemic GvHD (cGVHD), eyes, skin, oral mucosa and the hepatic system were commonly affected.[34] Chronic oGvHD occurred in 61.5–89.4% of cGvHD patients, with skin and oral involvement being highly indicative of risk for ocular involvement.[234] About 30%–33% of our allo-HSCT patients had ocular surface involvement, with altered impression cytology findings even in the absence of oGvHD.[23]

The group two patients have been described as those with cGvHD under methods, but are referred to as oGvHD patients elsewhere creating an ambiguity.

The authors[1] could have considered giving details of conditioning regimen and if this was the same for groups 1 and 2, as this can have implications in dry eye disease (DED). Addition of standard deviation and range to study parameters results and DED severity grades in oGvHD would have been helpful. Also, as per the authors Spanish NIH criteria requires Schirmer's of <5, however, the oGVHD patients' mean Schirmer's is stated as 9.4 and 8.64 which does not seem to corroborate. The interpretation of TBUT as nonsignificant in Branch-1 under Discussion is contradictory to the mention of significant P values under results. The authors' reference to Nassar et al.'s paper,[7] about the degree of punctate keratitis being evaluated by Oxford test and compared to Schirmer's for GVHD diagnosis or relationship of OSDI with systemic prognosis is inaccurate as both are not stated in the aforementioned paper. Also, the widely referenced paper on oGVHD diagnostic criteria by Ogawa et al.,[6] has been inaccurately stated in text as well as in reference number 16.

Changes in ocular surface evaluation parameters and their relevance in oGVHD has been widely researched.[236] The author's work on detection of CD8 + lymphocytes in conjunctiva of allo-HSCT patients without oGVHD is commendable which adds on to the evolving understanding of the disease.

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Conflicts of interest

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