TTC19 and FMNL2 gene variants in a pediatric case of mitochondrial disorder with renal tubular acidosis.
Prince Jacob, Sekar Deepha, Akhila Vasanth Hassan et al.
✦ AI-curated · Sources linked
Case in brief
A pediatric patient presented with developmental delay, failure to thrive, lactic acidosis, and distal renal tubular acidosis, raising suspicion for a mitochondrial disorder. Whole exome sequencing revealed a homozygous deletion in TTC19 and a novel splice-site variant in FMNL2. Functional studies confirmed mitochondrial dysfunction, expanding the clinical spectrum of TTC19-related disorders with early renal manifestations.
What made this case unusual
The case is notable for the early onset of renal tubular acidosis in a mitochondrial disorder, which is typically characterized by neurological symptoms in late childhood.
Diagnostic / clinical pearl
Clinicians should consider mitochondrial disorders in pediatric patients presenting with renal tubular acidosis and developmental delays, as atypical presentations can complicate diagnosis.
Why it matters
This case underscores the importance of genomic re-analysis and functional studies in understanding complex multisystem disorders, potentially guiding future diagnostic approaches.