Severe Thrombocytopenia and Facial Asymmetry in a Mexican Patient with Noonan Syndrome-Like Disorder with Loose Anagen Hair: Clinical Observations and Diagnostic Considerations.

INTRODUCTION

Noonan syndrome-like disorder with loose anagen hair 1 is a rasopathy caused by pathogenic variants in the SHOC2 gene, characterized mainly by short stature, facial dysmorphisms and ectodermal alterations.

CASE PRESENTATION: This case describes an 18-year-old female with the pathogenic variant c.4A>G in SHOC2, severe thrombocytopenia and facial asymmetry, features not currently considered part of the phenotype. While thrombocytopenia may be associated with the SHOC2 variant, a direct causal relationship cannot be definitively established, and the possibility of coexisting autoimmune disorders, such as systemic lupus erythematosus, could not be excluded.

CONCLUSION

This case underscores the importance of early molecular diagnosis and comprehensive hematological monitoring in patients with rasopathies, highlighting the potential for life-threatening complications. Systematic reviews involving larger cohorts are needed to better define the clinical spectrum of NSLH1 and refine management strategies for potential complications.