We thank Drs. Miller and Brealey1 for their comments and fully acknowledge their expertise in the field of electron microscopy. We also acknowledge our uncertainties regarding the exact nature of the particles seen in the podocytes in our patient’s kidney biopsy, and we were cautious in the interpretation of these findings. Following Drs. Miller and Brealey’s comments,1 we have modified our letter before its final publication in the journal to further underline that these particles may correspond to nonviral entities.
However, the particles detected in our patient’s biopsy are rather similar to the ones reported in the first documentation of severe acute respiratory syndrome coronavirus 2.2 Besides, the appearance of intracellular viral inclusions appears to be quite variable from one publication to another.3 , 4 To our opinion, it remains, therefore, possible that the particles observed in our patient are of viral origin. Nevertheless, we totally agree with Drs. Miller and Brealey1 that the definite proof for the presence of viral inclusions in cells requires an immunostaining with specific antibodies, whether in cultured cells or in tissue samples.
Our knowledge of coronavirus disease 2019 is rapidly evolving and caution is of the utmost importance.
References
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