A Case of Catastrophic Atypical Hemolytic Uremic Syndrome Unresponsive to Eculizumab and the use of Ravulizumab Off-label

Abstract

“A 40-year-old woman with melanoma, under treatment with Dabrafenib and Trametinib, was evaluated in our hospital for rapidly progressive deterioration of renal function”. 8 months before the current admission, the patient had been diagnosed with melanoma, and underwent radical surgery and subsequent therapy with Dabrafenib and Trametinib. After 5 months of therapy, the patient was brought to this hospital for precordial pain, with a diagnosis of myopericarditis, therapy was started for heart failure with a good response. However, the patient developed a progressive impairment of renal function, associated with hemolytic anemia and thrombocytopenia. The peripheral smear showed the presence of schistocytes. The suspicion of atypical Hemolytic Uremic Syndrome (aHUS) was confirmed by the assay of C5B-9 induced by serum on endothelial cells, which showed a deposition of 331%, treatment with Eculizumab was initiated. After 3 administrations the patient did not improve, with further worsening of the hemolytic condition, and progression of renal damage. Due to the failure of Eculizumab, we considered the use of Ravulizumab. However, in Italy only can be administered to patients in Eculizumab stable treatment for at least three months. Nevertheless, faced with the catastrophic condition, it was decided to shift the therapy and use off-label Ravulizumab. After 10 days of the first administration, the laboratory tests showed a continuous rise in the values of haptoglobin, platelets, and hemoglobin, and a decrease in LDH. The renal function failed to return to normal values but after 20 days of therapy with Ravulizumab, there was complete resolution of the hemolytic condition.