Authors: Hajar AlAkee , Abdullah AlZaben , Mohsen AlAtawi , Mhammed Aldubayee , Wafaa AlEyaid

Abstract

Background: Transaldolase deficiency (TALDO-D, Eyaid syndrome) is a rare autosomal recessive disorder of the
pentose phosphate pathway. It can present prenatally with intrauterine growth restriction or oligohydramnios; neonatally with dysmorphic features, cardiovascular defects, hepatosplenomegaly, anemia, and thrombocytopenia; or later with a milder phenotype. The present case report aimed at enhancing the effectiveness and confidence in treating patients with rare metabolic disorders that are further complicated by complex presentation.

Case Presentation: We present a rare case of a 14-year-old girl diagnosed with Eyaid Syndrome - TALDO-D based on clinical and molecular findings of a homozygous pathogenic variant in the TALDO1 gene, c.793del,p.(Gln265Argfs*56). She developed type 1 diabetes around the age of nine and was found to have a baseline non-anion gap metabolic acidosis that persisted despite adequate diabetes management. An extensive workup for possible renal causes, given that they are part of her primary syndrome, revealed proximal renal tubular acidosis. During an emergency department visit, she presented with abdominal pain, vomiting, diarrhea, and lethargy. Laboratories showed severe metabolic acidosis (pH of 6.93, HCO3–of 3.3), marking the beginning of her challenging management approach.

Conclusion: The patient in this case report has shown an excellent response to sodium bicarbonate in a well monitored clinical and biochemical setting. However, given the rarity and complexity of such cases, it isimperative to conduct a comprehensive literature review involving all relevant subspecialties and report similar challenging cases to establish evidence-based clinical practices for the high-quality management of this rare patient population.

Keywords: Transaldolase deficiency, mixed metabolic acidosis, DKA, RTA.