Extensive Bone Marrow Necrosis: Initial Presentation in Sickle Cell Anemia-A Case Report and Review of the Literature

Bone marrow necrosis and fat embolism syndrome in sickle cell disease during COVID-19 infection treated successfully with sequential red cell and plasma exchange

Fat embolism syndrome (FES) is a rare life-threatening condition that is particularly seen in milder forms of sickle cell disease (SCD). Widespread systemic fat emboli are generated in the context of extensive bone marrow necrosis. Multi-organ failure with a high morbidity and mortality may quickly develop. Infection with Parvovirus B19 is a common precipitant. Here, the authors report the case of a 35-year-old Afro-Caribbean man with HbSC disease who presented with FES having tested positive for SARS-COV-2. He rapidly became critically ill and required admission to the intensive care unit for organ support. He was treated with red cell exchange and plasma exchange and made a good recovery to leave hospital at week 7.

Qualitative and quantitative magnetic resonance imaging evaluation of bone tissue vaso-occlusive events in patients with sickle cell disease

OBJECTIVE

To evaluate the association between bone changes due to vaso-occlusive events in sickle cell disease (SCD) revealed by conventional MRI sequences and the fat fraction obtained using a 6-point DIXON technique (FFdix), in an attempt to use quantitative data as a biomarker for bone complications.

METHODS

Cross-sectional study, with 48 SCD patients, 26-homozygous (HbSS), and 22-compound heterozygous (HbSC). Forty-eight healthy individuals paired by age, weight, and sex with SCD patients. All participants underwent lumbar spine and pelvis MRI. Conventional sequences: bone complications related to vaso-occlusive events-femoral head avascular necrosis, bone infarctions, "H"-shaped vertebrae, bone marrow necrosis. Six-point DIXON technique: quantitative evaluation of the bone marrow at pre-established sites (lumbar vertebrae, sacrum, iliacs, femoral heads, greater femoral trochanters, femoral necks). Pearson's correlation, ROC curve, and binary logistic regression analysis were performed.

RESULTS

The most frequent findings in the SCD group included femoral head avascular necrosis (75%), bone infarctions (58.3%), "H"-shaped vertebrae (58.3%), and typical imaging findings of bone marrow necrosis (8.3%). Cortical bone thickness in the proximal femoral diaphysis in patients with SCD was moderately negatively correlated with FFdix in lumbar vertebrae, iliacs, femoral necks, and first sacral vertebrae. The ROC curves and odds ratios demonstrated excellent performance of FFdix in all the evaluated anatomical sites and identified patients having bone complications.

CONCLUSIONS

FFdix could serve as a potential biomarker in SCD because of its association with bone complications secondary to vaso-occlusive events in patients with SCD, especially in femoral heads, femoral necks, and iliacs.

Varied Age of First Presentation of Sickle Cell Disease: Case Presentations and Review

Sickle cell disease is a multisystem condition characterized by hemolytic anemia and vasoocclusion. Not only are the symptoms of the first presentation but also the ages of presentation are very variable. Following three case reports, different causes of possible late presentation are discussed. Many factors are responsible for the age at which sickle cell disease is diagnosed: doctor's delay (unfamiliarity with the disease), patient's delay (education and financial position of the parents, cultural factors), high- versus low-resource country (availability of newborn screening), fetal hemoglobin, reticulocyte count, and genetic modulators, such as SCD genotype, alpha-thalassemia, fetal hemoglobin concentration, and G6PD deficiency. The individual course of sickle cell disease depends on (epi) genetic and environmental properties and the underlying interactions. In further studies, the role of each factor should be evaluated more deeply, and its use as a marker of disease severity or activity should be assessed.

Neurologic recovery in systemic nontraumatic fat embolism syndrome in an elderly patient with hemoglobin SC disease: A case report

Cerebral fat embolism syndrome is an under-recognized yet well-known complication of bone marrow necrosis occurring in patients with sickle cell disease. We highlight a case manifested by multisystem organ failure in an elderly patient who attained neurologic recovery with prompt initiation of hematology consultation, RBC exchange, and supportive measures.