Baseline characteristics of patients with atypical haemolytic uraemic syndrome (aHUS): the Australian cohort in a global aHUS registry

Aims
To describe the baseline characteristics and treatment of Australian patients diagnosed with atypical haemolytic uraemic syndrome (aHUS) reported to the Global aHUS Registry.

Methods
Descriptive analysis of the Australian cohort with aHUS (n = 106) was undertaken for demographics, disease characteristics and prior treatment with eculizumab; comparing with the global cohort (n = 1688) for certain pre‐specified disease characteristics.

Results
In Australia, almost two‐thirds of patients diagnosed with aHUS were female and over 80% of patients were Caucasians, with similar proportions reported in the global cohort. Less than 6% of patients in the Australia and global cohorts were reported to have a history of autoimmune disease (4% vs 2%, respectively; P = 0.21) or cancer (5% vs 5%, respectively; P = 0.93), conditions that have been associated with secondary HUS. In the Australian cohort, 26% had received a kidney transplant and 68% of patients had received eculizumab. Kidneys were the most common organ involvement, followed by gastrointestinal tract (26%) and cardiovascular system (19%), with 35% of patients reported to have had at least 2 organs involved within 6 months prior to baseline visit or entry into the registry. Complement factor H (CFH) was the most common pathogenic complement gene variant in the Australian patients.

Conclusion
Data from the aHUS registry confirms and defines region‐specific disease characteristics among a selected group of Australian children and adults with aHUS reported to the registry. Ongoing and more inclusive data will provide further information about temporal trends and treatment outcomes, representing a unique opportunity for clinicians and researchers to further develop knowledge surrounding this rare disease.