Antiphospholipid syndrome and endocrine damage: why bilateral adrenal thrombosis?

We describe a rare case of bilateral hemorrhagic infarction of the adrenal glands diagnosed in the context of positive antiphospholipid antibodies (aPL). The patient presented atypical clinical symptoms of adrenal insufficiency. Laboratory investigation showed complete adrenal failure and increased aPL, both manifestations persisted 1 yr after the initial event. MR imaging at baseline was compatible with bilateral hemorrhagic infarction and showed almost complete loss of viable adrenal tissue 1 yr later. Although no direct causal effect can be proved, the sequence of events and the exclusion of other common causes of bilateral adrenal hemorrhage (e.g. tuberculosis, severe coagulation disorder) support an association between aPL and adrenal hemorrhagic infarction. A unique link between particular anatomical characteristics of the adrenal fascicular zone and a novel, previously described, explanation model of aPL-thrombosis is hypothesized. It is based on the properties of late endosomes, which are important organelles participating in cholesterol trafficking and protein sorting within cells and express epitopes recognized by aPL. It would be interesting to investigate adrenal tissue for presence of late endosomes and their aPL relevant epitopes for proof of this tempting hypothesis. Focal accumulation of aPL and isolated, simultaneous, bilateral adrenal infarctions could thus be explained.