RESUMO
BACKGROUND: Yellow nail syndrome (YNS) is a rare disease manifesting as a triad of yellow-green dystrophic nails, lymphedema, and chronic respiratory disease. The etiology of YNS is obscure and investigations are few. A single lymphatic pathogenesis has been proposed to account for all the associated features, and despite the lack of evidence for a unifying lymphatic mechanism, this hypothesis prevails. The objective was to explore the lymphatic phenotype in YNS and to establish whether lymphatic dysfunction could be a major contributing factor to the disease process. METHODS AND RESULTS: Four-limb lymphoscintigraphy was performed on patients with YNS and on healthy, age-matched controls. All 17 patients had lower limb swelling, and 14 (82%) had upper limb swelling also, including 5 (29%) with hand involvement. None of the YNS lymph scans was completely normal. Combined qualitative and quantitative assessment showed that 67% of YNS scans were clearly abnormal compared with 36% of healthy control scans. Mean axillary and ilio-inguinal nodal tracer uptakes were 41%-44% lower in the YNS group than in the controls (p < 0.0001). CONCLUSIONS: YNS is a lymphatic phenotype because lymphatic insufficiency was found to exist in all patients and the insufficiency was widespread (upper and lower limbs), with a common mechanistic fault of poor transport. The origin of the lymphatic fault is unclear. In healthy individuals, lymphatic abnormalities may be relatively common in the fifth decade of life onward.
Assuntos
Extremidade Inferior/diagnóstico por imagem , Anormalidades Linfáticas/diagnóstico por imagem , Sistema Linfático/diagnóstico por imagem , Linfocintigrafia/métodos , Síndrome das Unhas Amareladas/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Humanos , Anormalidades Linfáticas/genética , Masculino , Pessoa de Meia-Idade , Fenótipo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Síndrome das Unhas Amareladas/genéticaRESUMO
Yellow nail syndrome (YNS) is an uncommon disorder characterized by a triad of nail dystrophy, lymphedema, and pleural effusion. It is rare in children and congenital occurrence of YNS has been very rarely described. We report a 2-year-old Arab boy having congenital yellow nail syndrome with mild facial dysmorphism and bilateral conjunctival pigmentation born to consanguineous parents. One of his older siblings had died of nonimmune fetal hydrops (NIFH). The case supports the genetic basis of yellow nail syndrome with a possible relationship to nonimmune fetal hydrops.
