Objectives Erdheim–Chester disease (ECD) is a rare inflammatory disorder characterised by organ infiltration by non-Langerhans’ histiocytes. Although rare, ECD is clearly an overlooked diagnosis. No data specifically addressing the most frequent presentations of ECD at the time of onset in a large cohort of patients are currently available.

Methods We reviewed all the published cases in the English literature of histologically-confirmed ECD. We excluded reports in which data regarding onset and diagnosis were not univocal, as well as repeated reports of the same case(s). We also included in the analysis 10 new unpublished patients from our cohort. We analysed the disease presentation with particular regard to the manifestations that induced patients to seek medical attention and their subsequent evolution.

Results In the cumulative cohort of 259 cases, ECD predominantly presented with skeletal symptoms, diabetes insipidus, neurological and constitutional symptoms. Diabetes insipidus and constitutional symptoms, if not present at onset, seemed to only seldom develop. There were differences in ECD presentation and course among different age groups of patients.

Conclusions Physicians should be aware of the extraordinarily heterogeneous clinical presentations and manifestations of ECD in order to include ECD in the differential diagnosis of several conditions.