HbSE is a rare hemoglobinopathy with conflicting reports in the literature regarding potential complications. We report an 11-year old girl with HbSE disease and resultant bone infarction most likely due to vaso-occlusion. She had similar HbS and HbE levels as her sister, who has had no complications to date. We performed a literature review and identified a further 23 pediatric cases of Hemoglobin SE and although the majority of patients remained asymptomatic, up to 50% of children may suffer mostly vas-occlusive complications, some resulting in death. Infection and hyposplenism were uncommon. Further reports and case series of HbSE are needed to clarify the natural history of this rare hemoglobinopathy.

We report a child with persistently low SpO2 with delayed diagnosis due to the co-existing CPAM with possible AVM. The diagnosis was only achieved after low SpO2 incidentally discovered from the child's father. The eventual cause was Haemoglobin I-Toulouse, making both patients the first reported cases with low SpO2.