[Azygos continuation of the inferior vena cava associated with "H syndrome"]

The syndrome H is a rare autosomal recessive genetic disorder first described in 2008, caused by SLC29A3 gene mutations. It presents with variable cutaneous, joint, auditory, vascular, and hematologic features.

A 24-year-old man with recently diagnosed syndrome H presented with hyperpigmented patches on the lower abdomen and legs, sparing the joints, and splayed toe deformities. CT imaging revealed agenesis of the hepatic segment of the inferior vena cava (IVC) with a left-sided aberrant IVC draining via the azygos system into the superior vena cava. Inguinal lymphadenopathy and mild hepatomegaly were also noted. Lab results were normal. Skin biopsy confirmed dermal fibrosis with perivascular infiltrate.

This case illustrates the clinical variability of the syndrome H and the value of imaging in detecting rare vascular malformations such as IVC interruption, reported in only two other cases. Management is symptomatic, with a multidisciplinary approach and genetic counseling.