Work

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

Year: 2026

Type: article

Abstract: 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.

Source: Molecular Syndromology

DOI: 10.1159/000551580

Authors: Luis Felipe León-Madero, Andrea Stefanía Martínez-Balda, Carlos Alberto Venegas-Vega

Institutions: Hospital General de México, Instituto Nacional de Cancerología, Universidad Nacional Autónoma de México

Language: English

Topic: Protein Tyrosine Phosphatases

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: hybrid

Funder: Universidad Nacional Autónoma de México