Hajdu-Cheney syndrome: report of a case

End-Stage Renal Disease in an Infant With Hajdu-Cheney Syndrome

Hajdu-Cheney syndrome (HJCYS) is a rare, autosomal dominant, skeletal disorder caused by mutations in the NOTCH2 signaling pathway for which genetic testing has recently become available. Renal abnormalities are associated in at least 10% of cases. We present an 8-year-old Caucasian boy, born with multiple dysmorphic features consistent with HJCYS. Imaging of the urinary tract revealed bilateral cystic dysplastic kidneys with associated vesicoureteral reflux. Renal function has been impaired since birth and deteriorated progressively to end-stage renal disease (ESRD) by the age of two and a half years, when peritoneal dialysis was initiated and only recently renal transplantation was performed. Additional congenital abnormalities and multisystem involvement in HJCYS further complicated management, and he developed refractory anemia. Molecular diagnosis was confirmed by identification of a truncating mutation in exon 34 of NOTCH2. Although, renal abnormalities are considered an integral part of the HJCYS, published reports on ESRD are scarce. In those few published cases, where ESRD was recognized, renal failure developed either in late adolescence or adulthood. This is the first report of early ESRD occurring in a child. Patients with HJCYS may need chronic renal replacement therapy even in early childhood. The management of these children can be challenging given the multisystemic manifestations of HJCYS.

Lymphangiomatosis: clinical overview

"Lymphangiomatosis" is a general term for excessive growth of aberrant lymphatic vessels. The impact of lymphangiomatosis can be devastating due to osteolysis and/or multi-organ involvement. The disorders are heterogeneous, and treatment is dependent upon disease location and symptoms. Most reports are single cases or small case series, predominantly in the orthopedic and radiologic literature. Basic research focused on lymphatic disorders may translate into new therapies for these disorders.

Serpentine fibula-polycystic kidney syndrome caused by truncating mutations in NOTCH2

Serpentine fibula-polycystic kidney syndrome (SFPKS) is a rare disorder characterized by the association of craniofacial anomalies, radiological findings (wormian bones, elongated and bowed fibulae), polycystic kidneys, and normal intelligence. SFPKS shares many similarities with Hajdu-Cheney syndrome (HCS). We and others recently showed that truncating mutations in the last exon of NOTCH2 cause HCS. Here, we identify by Sanger sequencing two different heterozygous truncating mutations in the last exon of NOTCH2 in two unrelated patients with SFPKS. In one family, we show that the mutation occurred de novo. These findings demonstrate that SFPKS and HCS are both conditions caused by NOTCH2 mutations.

Hajdu-Cheney syndrome associated with serpentine fibulae and polycystic kidney disease

Six patients who presented with craniofacial anomalies, musculoskeletal anomalies including elongated and bowed (serpentine) fibulae, and polycystic kidneys are reported. This association of anomalies is referred to as serpentine fibula polycystic kidney syndrome (SFPKS) and is currently interpreted as a manifestation of Hajdu-Cheney syndrome (HCS). We report a new instance of this association of anomalies and review the clinical and radiographic features of HCS and of the reported cases of SFPKS.