Hypokalaemia and dysmorphia, is there a link?

Area of Science:

• Genetics
• Neurology
• Pediatrics

Background:

• Familial hypokalemic periodic paralysis (HypoPP) is a rare genetic disorder affecting muscle function.
• Andersen-Tawil syndrome (ATS) is a subtype of HypoPP characterized by periodic paralysis, cardiac arrhythmias, and dysmorphic features.
• 22q11.2 microdeletion syndrome is a common chromosomal disorder with a wide spectrum of clinical manifestations.

Observation:

• A 15-year-old male presented with new-onset quadriplegia and facial dysmorphia.
• His medical history revealed a maternal uncle with similar symptoms.
• Blood tests indicated severe hypokalemia and mild hypocalcemia.

Findings:

• Clinical diagnosis suggested Andersen-Tawil syndrome.
• Molecular genetic testing confirmed a diagnosis of familial hypokalemic periodic paralysis type 1.
• Simultaneously, a de novo 22q11.2 microdeletion syndrome was identified.

Implications:

• This case underscores the critical role of molecular diagnostics in identifying complex genetic disorders.
• The co-occurrence of HypoPP type 1 and 22q11.2 microdeletion syndrome highlights the genetic heterogeneity and diagnostic challenges in rare diseases.
• Accurate molecular diagnosis is essential for appropriate patient management and genetic counseling.