Background Atypical haemolytic uraemic syndrome (aHUS) is a severe life threatening disease with progression to end stage renal disease. Eculizumab, a humanised anti-C5 monoclonal antibody targeting the activated complement pathway, has been introduced as a therapy against aHUS.

Purpose To demonstrate the efficacy and safety of eculizumab in brief and sustained interruption of the thrombotic microangiopathy process, increase in the number of platelets and significant improvement in renal function in the long term with important reductions in the need for dialysis and plasmapheresis.

Material and methods Observational, retrospective and descriptive study of a patient with aHUS.

The information was obtained from the electronic clinical history (SELENE) and the pharmacy service managing software (Farmatools).

Results The patient was a 60-year-old woman who was hospitalised with renal failure symptoms (Cr 16.6 mg/dL) associated with severe anaemia (Hb 4.5 g/dL) and thrombopenia (platelets 111 000 U/µL) without previous infection. She was started on alternative renal therapy and red blood cell transfusion. Autoimmune studies were requested detecting ANCA+ antibodies and so steroid treatment was started, associated with cyclophosphamide with no response.

Due to thrombopenia persistence, we decided to start plasmapheresis with good response, stabilising haemoglobin and increasing the platelet count; however, renal failure function and MAT parameters persisted.

From the time of admission (7 January 2015 to 22 February 2015), she needed 14 plasmapheresis sessions and 2 cyclophosphamide boluses with active haemolysis pattern and so was dependent on substitutive renal therapy.

The patient started this therapy on 22 February 2015 with 4 doses, 900 mg/week, with good response. No further transfusions or plasmapheresis were needed, with an increase in platelet count (50 000 to 135 000 U/µL) and creatinine (7 to 5.42 mg/dL). After a week without this drug, analytical values got worse (platelets 111 000 U/µL and creatinine 11.71 mg/dL), and so eculizumad was authorised as maintenance therapy, 1200 mg/15 days.

After a month with this maintenance therapy, the result was an increase in platelet count up to 182 000 mg/dL, haemoglobin increase to 9.1 g/dL and creatinine increase to 7.33 mg/dL.

Conclusion FDA, EMA and AEMPS have approved the use of eculizumab for treating aHUA.

With this good response in this clinical case, eculizumab was effective in aHUS. However, the treatment’s high cost requires correct pathological identification in patients, so each case should be studied by a multidisciplinary team (haematology, nephrology and pharmacy).

References and/or Acknowledgements Eculizumab summary of product characteristics.

No conflict of interest.