Case report: splenic infarction and acute splenic sequestration in adults with hemoglobin SC disease

Safety and Efficacy of a Monoclonal Antibody against Malaria in Mali

BACKGROUND

CIS43LS is a monoclonal antibody that was shown to protect against controlled Plasmodium falciparum infection in a phase 1 clinical trial. Whether a monoclonal antibody can prevent P. falciparum infection in a region in which the infection is endemic is unknown.

METHODS

We conducted a phase 2 trial to assess the safety and efficacy of a single intravenous infusion of CIS43LS against P. falciparum infection in healthy adults in Mali over a 6-month malaria season. In Part A, safety was assessed at three escalating dose levels. In Part B, participants were randomly assigned (in a 1:1:1 ratio) to receive 10 mg of CIS43LS per kilogram of body weight, 40 mg of CIS43LS per kilogram, or placebo. The primary efficacy end point, assessed in a time-to-event analysis, was the first P. falciparum infection detected on blood-smear examination, which was performed at least every 2 weeks for 24 weeks. At enrollment, all the participants received artemether-lumefantrine to clear possible P. falciparum infection.

RESULTS

In Part B, 330 adults underwent randomization; 110 were assigned to each trial group. The risk of moderate headache was 3.3 times as high with 40 mg of CIS43LS per kilogram as with placebo. P. falciparum infections were detected on blood-smear examination in 39 participants (35.5%) who received 10 mg of CIS43LS per kilogram, 20 (18.2%) who received 40 mg of CIS43LS per kilogram, and 86 (78.2%) who received placebo. At 6 months, the efficacy of 40 mg of CIS43LS per kilogram as compared with placebo was 88.2% (adjusted 95% confidence interval [CI], 79.3 to 93.3; P<0.001), and the efficacy of 10 mg of CIS43LS per kilogram as compared with placebo was 75.0% (adjusted 95% CI, 61.0 to 84.0; P<0.001).

CONCLUSIONS

CIS43LS was protective against P. falciparum infection over a 6-month malaria season in Mali without evident safety concerns. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT04329104.).

Acute Splenic Sequestration Crisis in Hemoglobin SC Disease: Efficiency of Red Cell Exchange

Acute splenic sequestration crisis (ASSC) is recognized as a serious complication of sickle cell disease in children. ASSC presents with progressive splenic enlargement, transfusion-dependent anemia, and, eventually, circulatory compromise. ASSC is rare in adult patients, thus making its management and outcome in adults not well-defined. The purpose of this article is to describe our experience in managing ASSC in an adult female with hemoglobin (Hb) SC disease. The patient underwent an automated red blood cell (RBC) exchange, thus avoiding a planned splenectomy. To the best of our knowledge, our case is the third report in the literature on the use of RBC exchange in adults with HbSC disease and ASSC. RBC exchange should be considered in adults with HbSC disease with ASSC not responding to simple transfusion; a treatment that could alleviate patients' symptoms and avoid splenectomy complications, especially in young patients.

Acute Splenic Sequestration Crisis in a 70-Year-Old Patient With Hemoglobin SC Disease

A 70-year-old African American female with a past medical history significant for chronic bilateral shoulder pain and reported sickle cell trait presented with acute-onset bilateral thoracolumbar pain radiating to her left arm. Two days after admission, Hematology was consulted for severely worsening microcytic anemia and thrombocytopenia. Examination of the patient's peripheral blood smear from admission revealed no cell sickling, spherocytes, or schistocytes. Some targeting was noted. A Coombs test was negative. The patient was eventually transferred to the medical intensive care unit in respiratory distress. Hemoglobin electrophoresis confirmed a diagnosis of hemoglobin SC disease. A diagnosis of acute splenic sequestration crisis complicated by acute chest syndrome was crystallized, and red blood cell exchange transfusion was performed. Further research is necessary to fully elucidate the pathophysiology behind acute splenic sequestration crisis, and the role of splenectomy to treat hemoglobin SC disease patients should be better defined.

Beyond the definitions of the phenotypic complications of sickle cell disease: an update on management

The sickle hemoglobin is an abnormal hemoglobin due to point mutation (GAG → GTG) in exon 1 of the β globin gene resulting in the substitution of glutamic acid by valine at position 6 of the β globin polypeptide chain. Although the molecular lesion is a single-point mutation, the sickle gene is pleiotropic in nature causing multiple phenotypic expressions that constitute the various complications of sickle cell disease in general and sickle cell anemia in particular. The disease itself is chronic in nature but many of its complications are acute such as the recurrent acute painful crises (its hallmark), acute chest syndrome, and priapism. These complications vary considerably among patients, in the same patient with time, among countries and with age and sex. To date, there is no well-established consensus among providers on the management of the complications of sickle cell disease due in part to lack of evidence and in part to differences in the experience of providers. It is the aim of this paper to review available current approaches to manage the major complications of sickle cell disease. We hope that this will establish another preliminary forum among providers that may eventually lead the way to better outcomes.

Definitions of the phenotypic manifestations of sickle cell disease

Sickle cell disease (SCD) is a pleiotropic genetic disorder of hemoglobin that has profound multiorgan effects. The low prevalence of SCD ( approximately 100,000/US) has limited progress in clinical, basic, and translational research. Lack of a large, readily accessible population for clinical studies has contributed to the absence of standard definitions and diagnostic criteria for the numerous complications of SCD and inadequate understanding of SCD pathophysiology. In 2005, the Comprehensive Sickle Cell Centers initiated a project to establish consensus definitions of the most frequently occurring complications. A group of clinicians and scientists with extensive expertise in research and treatment of SCD gathered to identify and categorize the most common complications. From this group, a formal writing team was formed that further reviewed the literature, sought specialist input, and produced definitions in a standard format. This article provides an overview of the process and describes 12 body system categories and the most prevalent or severe complications within these categories. A detailed Appendix provides standardized definitions for all complications identified within each system. This report proposes use of these definitions for studies of SCD complications, so future studies can be comparably robust and treatment efficacy measured. Use of these definitions will support greater accuracy in genotype-phenotype studies, thereby achieving a better understanding of SCD pathophysiology. This should nevertheless be viewed as a dynamic rather than final document; phenotype descriptions should be reevaluated and revised periodically to provide the most current standard definitions as etiologic factors are better understood, and new diagnostic options are developed.

Outcome of splenectomy in children younger than 4 years with sickle cell disease

PURPOSE

Removal of the spleen in patients younger than 4 years has been reported to carry an increased risk of postsplenectomy sepsis and has not been universally accepted. We reviewed our experience with splenectomy in children with acute splenic sequestration crisis (ASSC) younger than 4 years.

METHODS

The study involved retrospective review of demographic and operative data, number of ASSC, operative complications, infections, and death.

RESULTS

From 1993 to 2008, 53 patients (28 males, 25 females) younger than 4 years had open (43.8%) or laparoscopic (56.6%) splenectomy after one or more events of ASSC. Six (11.3%) were younger than 18 months, 28 (52.8%) were 18 to 24 months old, and 21 (39.6%) were 24 to 48 months old. Operative complications were diaphragm laceration (laparoscopy, n = 3; 5.7%) and reoperation for bleeding (open, n = 1; 1.8%). Length of stay was similar for laparoscopic (3.6 days) vs open (3.8 days) splenectomy. Mean postoperative follow-up was 5.6 years. In 353 postsplenectomy admissions, 3 (5.7%) patients had positive blood cultures requiring treatment. Three (5.7%) patients died within the 15-year study period; one (1.8%) had documented pneumococcal sepsis.

DISCUSSION

The advantage of early splenectomy may outweigh the risks of long-term transfusion. Splenectomy in young children with sickle cell disease carries a low risk of postsplenectomy sepsis with appropriate vaccination and prophylactic antibiotics. We conclude that splenectomy in young children with ASSC is safe and effective, especially with penicillin prophylaxis and improved vaccination strategies.

Acute splenic complications and implications of splenectomy in hemoglobin SC disease

Splenectomy indications and outcome were evaluated in 124 adults with hemoglobin SC disease (Hb SC). Twelve patients (9.6%) required splenectomy. There was a significant difference between the splenectomy group and the non-splenectomy group, respectively, regarding Hb levels (median 7.2 g/dL vs. 12.5 g/dL, P < 0.0001), platelet counts (median 146 x 10(6)/L vs. 275 x 10(6)/L, P = 0.031), palpable spleen rate (66% vs. 16%, P = 0.0003%), acute chest syndrome frequency (75% vs. 12%P = 0.0004) and cholecystectomy rate (66% vs. 13%, P = 0.0004). No significant morbidity or mortality occurred postsplenectomy. There is a subgroup of Hb SC patients requiring splenectomy, in which splenectomy is effective. Although it appears to be safe regarding short-term complications of surgery, long-term adverse effects such as infections have to be evaluated cautiously.

Acute splenic sequestration in an adult with hemoglobin S-C disease

Acute splenic sequestration crisis is a common, potentially life-threatening complication of sickle cell anemia in children that is uncommon in adults.We present the case of a 44-year-old gentleman with undiagnosed hemoglobin S-C disease who developed intense back pain, marked abdominal distension, systemic inflammatory response syndrome, and multisystem organ failure that first presented as acute splenic sequestration crisis. The hemoglobinopathy SC is a disease caused by heterozygous-globin chain mutations with over-lapping clinical features of sickle cell disease with changes in the frequency of these manifestations reflected by the combination of characteristics of hemoglobin C and hemoglobin S. In hemoglobin S-C disease, autosplenectomy is rare and splenomegaly usually persists until adulthood;vasoocclusive complications are seen less habitually and become evident at a later time compared with sickle cell disease. The diagnosis of hemoglobin S-C disease is essentially done by exclusion. Transfusion of red blood cells is the treatment of choice, but splenectomy is indicated if transfusion therapy fails. A review of the literature and keypoints for the emergency practitioner are included.

Acute splenic sequestration crisis in adults with hemoglobin S-C disease: a report of nine cases

Acute splenic sequestration crisis (ASSC) is a potentially life-threatening complication and one of the leading causes of death in children with sickle cell disease. It is rarely reported in adults with hemoglobin S-C disease and its natural history in these patients has not been well studied. We describe here the clinicopathological features of ASSC in nine adults with hemoglobin S-C disease treated between 1972 and 2000 and followed for a mean period of 9 years (range 0-21 years). ASSC was characterized by acute left upper quadrant abdominal pain, splenomegaly, fever, and a rapid decrease in hematocrit with active erythropoiesis. The hemoglobin decreased by a mean of 4.8 g/dl from the steady state value (range 3.0 to 6.7 g/dl) during ASSC. Two patients failed to respond to transfusion of packed erythrocytes and required urgent splenectomy. There was one fatality-a 76-year-old woman, who died 36 h after admission. There was no recurrence of ASSC in five patients followed for 2, 3, 16, 18, and 21 years, respectively. ASSC in adults is a serious and occasionally, fatal complication of hemoglobin S-C disease. Patients with hemoglobin S-C disease may remain at risk of ASSC into their eighth decade.

La séquestration splénique aiguë : une complication rare et grave des syndromes drépanocytaires majeurs de l'adulte. À propos d'un cas

INTRODUCTION

Acute splenic sequestration, a well-recognized complication of sickle cell syndromes, is characterized by a sudden decrease in haemoglobin concentration and marked painless splenomegaly. We report a case illustrating the outcome and the treatment options of this complication.

CASE REPORT

A 45-year old homozygous woman developed acute splenic sequestration with severe anemia. Red blood cells transfusion led to transient improvement but a relapse-required splenectomy. Long-term outcome was favorable.

CONCLUSION

Acute splenic sequestration is a severe complication mainly observed in children. Despite the severity of this complication, prompt diagnosis and appropriate therapy, and particularly red blood cells transfusions, led to a complete recovery. Splenectomy is required in the more severe form of the disease.

Acute Splenic Sequestration Crisis Resembling Sepsis in an Adult with Hemoglobin SC Disease

Acute splenic sequestration crisis (ASSC) is a common complication of sickle cell anemia in children. ASSC is generally not seen in adults with the SS genotype but occasionally can be seen in adults with the SC genotype. We present a case of fulminant ASSC in an adult with hemoglobin SC who developed high fever, intense abdominal pain, leukocytosis, and jaundice.

Palpable splenomegaly in children with haemoglobin SC disease: haematological and clinical manifestations

This study aimed to investigate the prevalence of palpable splenomegaly in children with haemoglobin SC (Hb SC) disease, and to determine the haematological and clinical manifestations of splenomegaly in this patient population. We performed a retrospective chart review of 100 patients with Hb SC over 2 years of age followed by the Duke University Paediatric Sickle Cell Program with serial physical examinations and laboratory measurements. Palpable splenomegaly was present in 34% of patients and was more common in males (P = 0.029). Children with splenomegaly had a significantly lower average haemoglobin concentration (10.3 vs. 10.8 g/dl, P = 0.011) and lower platelet count (237 vs. 314 x 109/l, P < 0.001) than those without splenomegaly. Children with measurements both before and after the onset of splenomegaly had a significant decrease in the platelet count (279 vs. 216 x 109/l, P < 0.001) and white blood cell count (9.1 vs. 7.9 x 109/l, P = 0.04) after splenomegaly was identified. Clinical complications included acute splenic sequestration in 12% of children (median age 5.4 years), and hypersplenism with chronic thrombocytopenia in another 10% of patients (median age 10.6 years). Splenomegaly is a common physical finding in children with Hb SC disease and is often associated with mild cytopenias. Clinical complications of splenomegaly include acute splenic sequestration in younger patients and hypersplenism with chronic thrombocytopenia in older children.

Acute splenic complications in children with sickle cell-hemoglobin C disease

OBJECTIVE

To determine the frequency and severity of acute splenic complications in children and adolescents with sickle cell (SC) hemoglobin C disease.

METHODS

The medical records of 271 patients with SC disease seen at our center were reviewed to evaluate the incidence and severity of acute complications involving the spleen.

RESULTS

Sixteen (6%) children had acute splenic complications. Thirteen (5%) had 16 episodes of acute splenic sequestration (ASSC), with the initial event occurring at a mean age of 8.9 years (range, 2 to 17 years). Splenomegaly had been noted before the initial event in 6 (46%) of the 13 cases, and 3 (23%) had a history of painful splenic infarction. Two young children (aged 4 and 6 years) had a hemoglobin value less than 2 gm/dl, one without history of splenic enlargement. Three (23%) children had a second episode of ASSC. Three additional patients had a history of acute painful splenic infarction, two of whom also had splenic hemorrhage. Eight (3%) of the 271 children required splenectomy (1 after the initial episode of ASSC, 3 after a second episode of ASSC, 2 as a result of pain accompanying chronic infarction and ASSC, and 2 because of splenic hemorrhage). No deaths resulted from ASSC.

CONCLUSIONS

We conclude that (1) acute splenic complications in children and adolescents with SC disease are relatively uncommon, (2) most episodes of ASSC occur in preadolescents, (3) ASSC can be life threatening, even in younger children, and (4) prior splenomegaly is not a good predictor of ASSC. Thus it is vital that the parents of all children with SC disease be instructed to palpate their child's spleen regularly.

Hematologic profile and lymphocyte subpopulations in hemoglobin SC disease: comparison with hemoglobin SS and black controls. The Transfusion Safety Study Group

Compared with subjects with homozygous SS disease (Hb SS), persons with hemoglobin SC (Hb SC) are known to have a more gradual loss of splenic function, a lower incidence of bacterial infections, and fewer end-organ failures. We studied hematological indices and lymphocyte subpopulations of 27 Hb SC subjects and compared them with 173 Hb SS patients and 131 black controls. Hb SC patients had higher hemoglobin levels than Hb SS subjects, lower total leukocyte, granulocyte, monocyte, and lymphocyte counts. Platelets decreased with age but not significantly, instead of increasing as among Hb SS patients. Mononuclear cells were generally similar to controls with the exception of CD8+HLA-DR+ counts resembling Hb SS. Hematologic changes in Hb SC are limited to moderate granulocytosis in children and adults, mild monocytosis in adults, and increased activation of just one lymphocyte subset among those measured.

Splenic infarct presenting as acute abdominal pain in an older patient

A 67-year-old female presented to the Emergency Department with a several hour history of severe pain in the left upper quadrant. A computed tomographic study (CT scan) of the abdomen demonstrated a splenic infarct. The patient was subsequently found to have a patent foramen ovale, with a small right-to-left shunt. This patient's splenic infarct is considered to be embolic in etiology, either from the patent foramen ovale or severe atherosclerotic disease. Patients with left upper quadrant pain who do not have the etiology differentiated by initial testing should be considered to have the potential for splenic infarction. This case illustrates the uncommon occurrence of splenic infarction, presenting as left upper quadrant pain.

Case report: splenic sequestration and multiorgan failure as the presenting manifestation of hemoglobin SC disease

Acute splenic sequestration, a well recognized complication of the various sickle cell syndromes, is characterized by increasing splenomegaly and a sudden fall in hemoglobin concentration. In this article, the authors describe a 21-year-old woman with previously undiagnosed hemoglobin SC disease whose initial presentation was that of acute, severe splenic sequestration. Despite the severity of her illness, prompt diagnosis and appropriate therapy led to a complete recovery. The splenic sequestration in this case was apparently exacerbated by a recent hepatitis B infection. To date, this presentation of hemoglobin SC disease has not been described in the medical literature.