RESUMO
Patients with X-linked hyperimmunoglobulin M syndrome (XHIGM) have a defective CD40-CD40 ligand system and further immunoglobulin class-switching. They may present with recurrent infection and malignancy involving the liver, pancreas or biliary tract. We report here a case of poorly differentiated transitional cell carcinoma in a young man with XHIGM even on regular treatment and discuss the possible pathogenesis. Given that the triggering of the CD40-CD40 ligand system has been found to improve tumor immunogenicity in recent studies, future immunotherapy targeting the CD40 ligand for these patients may be feasible to prolong their survival.
Assuntos
Carcinoma de Células de Transição/diagnóstico , Síndrome de Imunodeficiência com Hiper-IgM Tipo 1/diagnóstico , Neoplasias Renais/diagnóstico , Adulto , Carcinoma de Células de Transição/complicações , Carcinoma de Células de Transição/terapia , Humanos , Síndrome de Imunodeficiência com Hiper-IgM Tipo 1/complicações , Síndrome de Imunodeficiência com Hiper-IgM Tipo 1/terapia , Neoplasias Renais/complicações , Neoplasias Renais/terapia , MasculinoRESUMO
BACKGROUND: Hereditary angioedema (HAE) is a rare disorder characterized by recurrent attacks of localized subcutaneous or submucosal edema. It is inherited in an autosomal dominant fashion and caused by a deficiency of C1 inhibitor (C1 INH). Most patients with HAE have an absolute deficiency of C1 INH (type I HAE), whereas the rest (approximately 15%) synthesize a dysfunctional C1 INH protein (type II HAE). Mosaicism is rare in HAE. OBJECTIVE: To describe the clinical manifestations, laboratory findings, and molecular genetic studies in a Taiwanese family with type I HAE with paternal mosaicism. METHODS: A family that included a 34-year-old man (index patient) and his 25-year-old brother who both had recurrent peripheral angioedema was evaluated. A younger sister had died of an unexplained cause at 18 years of age. We analyzed blood levels of C3, C4, and C1 INH and sequenced the SERPING] (C1NH) gene that codes for C1 INH in 5 family members, including the parents and 3 brothers. RESULTS: The 4 men in the family had a novel mutation c.3_73del, p.N1fsX34 in exon 3 of the C1INH gene, resulting in C1 INH deficiency. Although the father carried this mutant gene, he had normal serum levels of C1 INH. Based on quantitative analysis of allele dosage by DNA fragment analysis (GeneScan), the father was determined to have genetic mosaicism. CONCLUSION: Parental mosaicism is a possible explanation for normal C1 INH plasma concentrations in both parents despite clinically apparent HAE in the children.