Reply:
======

* N. Kadom
* R.C. Castellino
* D.S. Wolf

We appreciate that Guerrini-Rousseau and colleagues are raising awareness for constitutional mismatch repair deficiency (CMMRD) syndrome and its phenotypical overlap with neurofibromatosis type 1 (NF-1). All 5 patients described in our article met clinical criteria for NF-1 (Table). None of the patients reported had confirmatory genetic testing; for children who meet the clinical criteria, genetic testing is not typically obtained.

View this table:
[Table1](http://www.ajnr.org/content/40/6/E32/T1)

For a diagnosis of NF-1, at least 2 of the diagnostic criteria should be present3

CMMRD is rare (200 patients reported), and our patients had none of the other diagnostic criteria of CMMRD.1 Café au lait spots are common (up to 97%) in CMMRD, but the other clinical manifestations of NF-1 are much less frequent.2 Focal abnormal signal intensities have also been reported in CMMRD.

## REFERENCES

1.  1. Wimmer K, Kratz CP, Vasen HF, et al; EU-Consortium Care for CMMRD (C4CMMRD). Diagnostic criteria for constitutional mismatch repair deficiency syndrome: suggestions of the European consortium ‘care for CMMRD’ (C4CMMRD). J Med Genet 2014;51:355–65 doi:10.1136/jmedgenet-2014-102284 pmid:24737826
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6OToiam1lZGdlbmV0IjtzOjU6InJlc2lkIjtzOjg6IjUxLzYvMzU1IjtzOjQ6ImF0b20iO3M6MTk6Ii9ham5yLzQwLzYvRTMyLmF0b20iO31zOjg6ImZyYWdtZW50IjtzOjA6IiI7fQ==) 

2.  2. Wimmer K, Rosenbaum T, Messiaen L. Connections between constitutional mismatch repair deficiency syndrome and neurofibromatosis type 1. Clin Genet 2017;91:507–19 doi:10.1111/cge.12904 pmid:27779754
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1111/cge.12904&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=27779754&link_type=MED&atom=%2Fajnr%2F40%2F6%2FE32.atom) 

3.  3. Friedman JM. Neurofibromatosis 1. October 2, 1998, updated May 17, 2018. GeneReviews® [Internet]. [https://www.ncbi.nlm.nih.gov/books/NBK1109/](https://www.ncbi.nlm.nih.gov/books/NBK1109/). Accessed April 21, 2019. 
    
    

*   © 2019 by American Journal of Neuroradiology