Resumen
Introducción: Cuando un cromosoma sufre 2 rupturas distales y los extremos rotos se unen, forman un cromosoma en anillo. El síndrome del anillo 21 se describe con un fenotipo con dismorfias menores, trombocitopenia, retraso psicomotor y del lenguaje. El objetivo de este trabajo es presentar 2 casos de pacientes del sexo masculino con cromosoma 21 en anillo.
Casos clínicos: el primer caso fue un paciente de 5 años con retraso en el desarrollo psicomotor y del lenguaje, frente amplia con sutura metópica prominente, pliegue epicántico bilateral, hipotelorismo, endotropia izquierda, pabellones auriculares asimétricos de baja implantación, micrognatia, extremidades inferiores con pliegues plantares profundos.
Su cariotipo fue 46,XY,r(21)(p11.2q21)[25]. El segundo caso fue un paciente de 8 años con retraso en el desarrollo psicomotor y del lenguaje, cráneo con occipucio aplanado, facies triangular, aplanamiento mediofacial, fisuras palpebrales dirigidas hacia abajo, pliegue epicántico bilateral, pabellones auriculares de implantación baja y asimétricos, micrognatia, tórax asimétrico prominente del lado derecho y manos con líneas palmares irregulares. Su cariotipo fue 46,XY,r(21) (p11q22)[25].
Conclusión: las dismorfias craneofaciales con retraso psicomotor y del lenguaje fueron los datos clínicos más relevantes en ambos casos.
Abstract
Background: When a chromosome undergoes 2 distal breaks and the broken ends join together, they form a ring chromosome. Ring 21 syndrome is described with a phenotype with minor dysmorphisms, thrombocytopenia, psychomotor and language delay. The objective of this work is to display 2 cases of male patients with ring chromosome 21.
Clinical cases: The first case was a 5-year-old male patient, with psychomotor and language delay. Broad forehead with prominent metopic suture, bilateral epicanthic fold, hypotelorism, left esotropia, low-set asymmetrical pinnae, micrognathia, lower extremities with deep plantar folds. Karyotype 46,XY,r(21)(p11.2q21)[25]. The second case was an 8-year-old male patient with psychomotor and language delay. Skull with flattened occiput, triangular facies, midfacial flattening, palpebral fissures directed downwards, bilateral epicanthic fold, low-set and asymmetrical pinnae, micrognathia, prominent asymmetrical thorax on the right side, hands with irregular palmar folds. Karyotype: 46,XY,r(21) (p11q22)[25].
Conclusion: Craniofacial dysmorphisms with psychomotor and language delay were the most relevant clinical data in both cases.
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