[Diagnostic and therapeutic guidelines of thrombotic microangiopathies of the Spanish Apheresis Group]

Management of atypical uremic hemolytic syndrome in pregnant patient

Atypical uremic haemolytic syndrome is a variant of thrombotic micro-andiopathy characterized by non-autoimmune hemolytic anemia, thrombocytopenia and acute renal failure as a result of excessive activation of the complement. Up to 60% of patients have mutations in the genes that encode the complement system. A disensing factor is required for its manifestation, including gestation. It is an entity with a high morbidity, which can decrease drastically if an early diagnosis is made and appropriate treatment is initiated. Administration of ecuilizumab has demonstrated rapid process disruption, reducing the need for extrarenal purification therapies and improving renal function and patient prognosis.

Effectiveness of Caplacizumab Nanobody in Acquired Thrombotic Thrombocytopenic Purpura Refractory to Conventional Treatment

Acquired thrombocytopenic thrombotic purpura (aTTP) is an autoantibody-mediated disease against the enzyme A Disintegrin and Metalloprotease domain with ThromboSpondin-1 type motif 13, which until now has been treated with plasma exchange (PEX) and corticosteroids. A 29-year-old female patient, who presented with aTTP in the context of pregnancy, has developed multiple relapses after treatment with PEX, corticosteroids, and rituximab. Recently, caplacizumab, a nanobody against von Willebrand factor, has been approved for the treatment of aTTP. In our patient, caplacizumab achieved better disease control, with a lower platelet count restoration time, days of PEX and hospitalization duration, as compared to standard therapy, reproducing the results of clinical trials. Caplacizumab represents a significant advance in the treatment of aTTP, especially in cases of recurrent relapses.

Management of atypical uremic hemolytic syndrome in pregnant patient

Atypical uremic haemolytic syndrome is a variant of thrombotic micro-andiopathy characterized by non-autoimmune hemolytic anemia, thrombocytopenia and acute renal failure as a result of excessive activation of the complement. Up to 60% of patients have mutations in the genes that encode the complement system. A disensing factor is required for its manifestation, including gestation. It is an entity with a high morbidity, which can decrease drastically if an early diagnosis is made and appropriate treatment is initiated. Administration of ecuilizumab has demonstrated rapid process disruption, reducing the need for extrarenal purification therapies and improving renal function and patient prognosis.

A critical evaluation of caplacizumab for the treatment of acquired thrombotic thrombocytopenic purpura

Introduction: Acquired thrombotic thrombocytopenic purpura (aTTP) is a thrombotic microangiopathy caused by inhibitory autoantibodies against ADAMTS13 protein. Until recently, the combination of plasma exchange (PEX) and immunosuppression has been the standard front-line treatment in this disorder. However, aTTP-related mortality, refractoriness, and relapse are still a matter of concern. Areas covered: The better understanding of the pathophysiological mechanisms of aTTP has allowed substantial improvements in the diagnosis and treatment of this disease. Recently, the novel anti-VWF nanobody caplacizumab has been approved for acute episodes of aTTP. Caplacizumab is capable to block the adhesion of platelets to VWF, therefore inhibiting microthrombi formation in the ADAMTS13-deficient circulation. In this review, the characteristics of caplacizumab together with the available data of its efficacy and safety in the clinical setting will be analyzed. Besides, the current scenario of aTTP treatment will be provided, including the role of other innovative drugs. Expert opinion: With no doubt, caplacizumab is going to change the way we treat aTTP. In combination with standard treatment, caplacizumab can help to significantly reduce aTTP-related mortality and morbidity and could spare potential long-term consequences by minimizing the risk of exacerbation.

Hemolytic uremic syndrome in adults: A case report

Thrombotic microangiopathies (TMA) are microvascular occlusive disorders characterized by platelet aggregation and mechanical damage to erythrocytes, clinically characterized by microangiopatic haemolytic anemia, thrombocytopenia and organ injury. We are reporting a case of a woman patient with severe hemolytic uremic syndrome associated to infectious diarrhoea caused by Shiga toxin-producing pathogen, who were admitted to our intensive care unit. The patient described developed as organ injury, neurological failure and acute renal failure, with need of haemodialysis technique. Due to the severity of the case and the delay in the results of the additional test that help us to the final diagnose, we treated her based on a syndromic approach of TMA with plasma exchange, with favourable clinical evolution with complete recovery of organ failures. We focus on the syndromic approach of these diseases, because thrombotic thrombocytopenic purpura, one of the disorders that are included in the syndromes of TMA, is considered a haematological urgency given their high mortality without treatment; and also review the TMA in adults: Their pathogenesis, management and outcomes.

Adjustment of Eculizumab Dosage Pattern in Patients with Atypical Hemolytic Uremic Syndrome with Suboptimal Response to Standard Treatment Pattern

In patients with atypical hemolytic uremic syndrome (aHUS), complement blocking by eculizumab rapidly halts the process of thrombotic microangiopathy and it is associated with clear long-term hematologic and renal improvements. Eculizumab treatment consists of a 4-week initial phase with weekly IV administration of 900 mg doses, followed by a maintenance phase with a 1,200 mg dose in the fifth week and every 14±2 days thereafter. We present three patients with aHUS and suboptimal response to eculizumab treatment at the usual administration dosage who showed hematologic and renal improvements after an adjustment in the eculizumab treatment protocol.