RESUMEN
BACKGROUND: Infant acute lymphoblastic leukemia (ALL) has never occurred in families except for the â¼100% concordant cases in monozygous twins attributed to twin-to-twin metastases. We report the first kindred with infant ALL in non-twin siblings. The siblings were diagnosed with MLL-rearranged (MLL-R) ALL 26 months apart. The second affected sibling had an unaffected dichorionic monozygous co-twin. Both had fatal outcomes. PROCEDURES: Translocations were characterized by karyotype, FISH, multiplex FISH, and MLL breakpoint cluster region (bcr) Southern blot analysis. Breakpoint junctions and fusion transcripts were cloned by PCR. TP53 mutation and NADPH quinone oxidorecuctase 1 (NQO1) C609T analyses were performed, and pedigree history and parental occupations were ascertained. The likelihood of chance occurrence of infant ALL in non-twin siblings was computed based on a binomial distribution. Zygosity was determined by single nucleotide polymorphism (SNP) array. RESULTS: The translocations were not related or vertically transmitted. The complex karyotype of the proband's ALL had chromosome 2, 3, 4, and 11 abnormalities causing a 5'-MLL-AFF1-3' fusion and a non-productive rearrangement of 3'MLL with a chromosome 3q intergenic region. The affected twin's ALL exhibited a simple t(4;11). The complex karyotype of the proband's ALL suggested a genotoxic insult, but no exposure was identified. There was no germline TP53 mutation. The NQO1 C609T risk allele was absent. The likelihood of infant ALL occurring in non-twin siblings by chance alone is one in 1.198 × 10(9) families. CONCLUSIONS: Whether because of a deleterious transplacental exposure, novel predisposition syndrome, or exceedingly rare chance occurrence, MLL-R infant ALL can occur in non-twin siblings. The discordant occurrence of infant ALL in the monozygous twins was likely because they were dichorionic.
Asunto(s)
Cromosomas Humanos/genética , Reordenamiento Génico , N-Metiltransferasa de Histona-Lisina/genética , Proteína de la Leucemia Mieloide-Linfoide/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Hermanos , Translocación Genética , Gemelos Dicigóticos , Humanos , Lactante , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologíaRESUMEN
Previous studies have shown that thyroid hormone directly stimulates bone resorption in in vitro organ culture, and in adults excess thyroid hormone is associated with decreased bone mineral density. There are limited data in children regarding the effect of hyperthyroidism on bone metabolism and even fewer instances in the literature of hyperthyroidism presenting with bone demineralization and fracture. We report a case of an 11-year-old boy with undiagnosed hyperthyroidism presenting with fractures and osteoporosis. This case emphasizes the importance of maintaining a broad differential diagnosis when a patient presents with a pathologic fracture.
Asunto(s)
Enfermedad de Graves/diagnóstico , Osteoporosis/etiología , Fracturas Osteoporóticas/etiología , Fracturas del Radio/etiología , Fracturas de la Columna Vertebral/etiología , Vértebras Torácicas/lesiones , Niño , Enfermedad de Graves/complicaciones , Humanos , Masculino , Osteoporosis/diagnóstico , Fracturas Osteoporóticas/diagnóstico por imagen , Radiografía , Fracturas del Radio/diagnóstico por imagen , Fracturas de la Columna Vertebral/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagenRESUMEN
Achromobacter xylosoxidans is a rare, opportunistic infection most commonly encountered in immunocompromised patients during hospitalization. Primary uncomplicated bacteremia, catheter-associated infections, and pneumonia have been reported as the most common clinical presentations; skin and soft tissue infections from A. xylosoxidans are rare. We describe a case of A. xylosoxidans presenting as cellulitis and bacteremia in an immunocompromised patient.