RESUMEN
Vitamin D-dependent type 1A rickets (VDDR-1A) is a rare autosomal recessive disease due to the inability to convert 25-hydroxyvitamin D [25(OH)D] to the active form 1.25-dihydroxyvitamin D [1.25(OH) 2 D] by the enzyme 25(OH)D-1α-hydroxylase leading to low or low-normal serum levels of [1.25(OH) 2 D]. We report two sisters with rickets in whom the diagnosis of VDDR-1A was a challenge. They had normal 1.25(OH)2D levels, which are unusual with this condition but may be explained by the identified genotype. Both have compound heterozygous for two, most likely, hypomorphic CYP27B1 alleles: the novel p.(Arg117Gly) variant, and p.(Ala129Thr), which are present in 0.43% of the African population. This report illustrates the variability of clinical, laboratory, and radiological presentation between two sisters with the same genotype, during phases of faster or slower growth. Genetic testing was crucial for establishing the diagnosis that optimized the management and genetic counseling.
RESUMEN
Spinal cord ischaemia is a rare condition in children in which imaging diagnosis can be difficult and treatment guidelines are not well established. We describe a case of a previously healthy 13-year-old girl admitted to the emergency department with an acute flaccid paralysis of the lower limbs, abdominal and dorsal pain, and bladder dysfunction. A few hours earlier, she had been playing on a swing with hyperextension and an arched back position. Spinal cord MRI was normal in the first hours, but ischaemic signs were described in a second examination performed some hours later. We discuss the extensive investigation for differential diagnosis and the management of this case.
