Response to Grzybowski and Justynska

Sir,

We thank Dr Grzybowski and Justynska¹ for their interest in our article.

In response to their comments on our report² we acknowledge the inadvertent omission of articles that emphasize the occurrence of inflammatory-marker-negative disease seen in giant cell arteritis (GCA). Unfortunately some papers referred to were not published at the time of writing.^{3, 4} The table provided by Dr Grzybowski and Justynska highlights some important articles, some of which were referenced in our original report⁵ and others which were summarized by key articles referenced.^{6, 7, 8}

Dr Grzybowski and Justynska remark that typical features commonly associated with GCA were not presented in our case. However, the patient we described was indeed unique in that the patient did not display symptoms usually found in GCA other than AION-induced loss of vision and corresponding RAPD in a patient with known polymyalgia rheumatica. These features were described in our report. We fully agree that scrutinizing the clinical picture is critical in the diagnosis of GCA but would like to emphasize that this is exactly what we did. We specifically looked at the clinical presentation including increased pre-test probability due to ethnicity in order to come to the conclusion that the negative CRP needed to be ignored!

We are very grateful for the additional case reports and have integrated them into our original table, thereby giving a more detailed understanding of inflammatory-marker-negative disease (Table 1).

Table 1 Summary of current literature—revised and updated according to comments by Grzybowski and Justynska