Emergency red cell exchange for the management of acute complications in sickle cell disease: Automated versus manual.

BACKGROUND: Red blood cell exchange is the cornerstone of the management for acute complications of sickle cell disease. It improves anaemia and improvesperipheral tissue oxygen delivery while at the same time reduces the proportion of circulating sickle erythrocytes. Even though automated red cell exchange is very effective in rapidly lowering the Hb S level, 24-h availability is currently not feasible for most specialist centres including our own. OBJECTIVE: Here, we describe our experience using both automated and manual red cell exchange for the management of acute sickle cell complications. METHODS: Eighty-six such episodes have been recorded between June 2011 and June 2022 comprising of 68 episodes of automated and 18 episodes of manual red cell exchange. RESULTS: The post procedure Hb S/S + C level was 18% after automated and 36% after manual red cell exchange. The platelet count dropped by 41% and 21% after automated and manual red cell exchange respectively. The clinical outcomes including need for organ support, duration of stay in the intensive care unit and overall length of hospitalisation was comparable between the two groups. CONCLUSION: In our experience, manual red cell exchange is a safe and effective alternative to an automated procedure that can be used while specialist centres are building up their capacity to offer automated red cell exchange for all patients requiring the intervention.

Rate of Dental Extractions in Patients with Sickle Cell Disease.

BACKGROUND: Sickle cell disease is an inherited disorder associated with chronic haemolysis and anaemia, recurrent episodes of pain and potentially multisystem end-organ damage. A lot less is known about the dental health of these patients. AIMS: To explore the incidence of severe dental disease leading to dental extraction in our sickle cell population. PATIENT/METHODS: We undertook an audit looking at the rate of dental extractions, as a composite marker of severe dental disease, among sickle cell patients over a 3-month period. The patients were unselected and approached during routine assessments. We analysed both clinical and laboratory data to look for possible associations between dental disease and sickle cell characteristics. RESULTS: 177 patients were interviewed between February 2022 and April 2022. Overall, 71% of the patients had at least one dental extraction with a median number of teeth extracted of three and a median age at first extraction of 26. More than half of the patients stated that they do not have regular dental check-ups. There were no significant associations with the severity of sickle cell phenotype, baseline Hb or markers of haemolysis. CONCLUSION: A large number of patients with sickle cell disease require dental extractions at a relatively young age. The lack of any correlation with disease severity suggests that poor engagement with dental services and the underestimation of the importance of dental health are the main factors behind the increased prevalence of severe dental disease. Actively enquiring about dental problems should be part of any routine consultation with these patients, both in primary and specialist care.

Tocilizumab in the management of posttransfusion hyperhemolysis syndrome in sickle cell disease: The experience so far.

BACKGROUND: Posttransfusion hyperhemolysis syndrome is a rare but life-threatening form of delayed hemolytic transfusion reaction with lysis of both transfused and autologous red cells, seen predominantly in patients with sickle cell disease. Macrophage activation is thought to play a major role in its pathophysiology. Standard treatment is with intravenous immunoglobulin and steroids but refractory cases pose a major clinical problem. Tocilizumab is a humanized monoclonal antibody against the IL-6 receptor that can inhibit IL-6 induced macrophage activation. METHODS AND MATERIALS: We describe the case of a 33-year-old woman with sickle cell anemia and posttransfusion hyper hemolysis syndrome refractory to standard therapy, treated with Tocilizumab. We also review all cases reported in the literature where Tocilizumab was used for posttransfusion hyperhemolysis. RESULTS: Treatment with Tocilizumab was well tolerated with no observed adverse events. There was no further drop in Hb after day 2 of treatment with subsequent continuous gradual improvement. Her bilirubin dropped significantly after the first dose and continued to improve, while ferritin and LDH reduced significantly after day 2 of treatment with Tocilizumab and continued to drop thereafter. Like in our case, all other cases in the literature where Tocilizumab was used for posttransfusion hyperhemolysis led to rapid clinical responses and no adverse events. DISCUSSION: Even though the number of cases of posttransfusion hyper hemolysis syndrome treated with Tocilizumab are few, they have all been associated with rapid clinical responses with no observed adverse events suggesting that the role of Tocilizumab in this context needs to be further explored.

Automated Red Cell Exchange in the Management of Sickle Cell Disease.

Red cell transfusion represents one of the cornerstones of the chronic management of sickle cell disease, as well as its acute complications. Automated red cell exchange can rapidly lower the number of circulating sickle erythrocytes, without causing iron overload. Here, we describe our experience, having offered this intervention since 2011. A transient reduction in the platelet count by 61% was observed after the procedure. This was not associated with any haemorrhagic complications. Despite exposure to large volumes of blood, the alloimmunisation rate was only 0.027/100 units of red cells. The absence of any iron loading was confirmed by serial Ferriscans, performed over a number of years. However, patients with advanced chronic kidney disease showed evidence of iron loading due to reduced innate haemopoiesis and were subsequently switched to simple transfusions. A total of 59% of patients were on regular automated red cell exchange with a history of recurrent painful crises. A total of 77% responded clinically, as evidenced by at least a 25% reduction in their emergency hospital attendance for pain management. The clinical response was gradual and increased the longer patients stayed on the program. The earliest sign of clinical response was a reduction in the length of stay when these patients were hospitalised, indicating that a reduction in the severity of crises precedes the reduction in their frequency. Automated red cell exchange also appeared to be beneficial for patients with recurrent leg ulcers and severe, drug resistant stuttering priapism, while patients with pulmonary hypertension showed a dramatic improvement in their symptoms as well as echocardiographic parameters.