Blunt traumatic injury is one of the leading causes of morbidity and mortality in the United States. Unintentional injury represents the leading cause of death in the United States for all persons between the ages of 1 and 44 years. In the setting of blunt abdominal trauma, the reported rate of occurrence of bowel and mesenteric injuries ranges from 1% to 5%. Despite the relatively low rate of blunt bowel and mesenteric injury in patients with abdominal and pelvic trauma, delays in diagnosis are associated with increased rates of sepsis, a prolonged course in the intensive care unit, and increased mortality. During the past 2 decades, as multidetector computed tomography (CT) has emerged as an essential tool in emergency radiology, several direct and indirect imaging features have been identified that are associated with blunt bowel and mesenteric injury. The imaging findings in cases of blunt bowel and mesenteric injury can be subtle and may be seen in the setting of multiple complex injuries, such as multiple solid-organ injuries and spinal fractures. Familiarity with the various imaging features of blunt bowel and mesenteric injury, as well as an understanding of their clinical importance with regard to the care of the patient, is essential to making a timely diagnosis. Once radiologists are familiar with the spectrum of findings of blunt bowel and mesenteric injury, they will be able to make timely diagnoses that will lead to improved patient outcomes. RSNA, 2017.

Fetal hemoglobin (HbF) is a major modifier of disease severity in sickle cell anemia (SCA). Three major HbF quantitative trait loci (QTL) are known: the Xmn I site upstream of Gγ-globin gene (HBG2) on chromosome 11p15, BCL11A on chromosome 2p16, and HBS1L-MYB intergenic polymorphism (HMIP) on chromosome 6q23. However, the roles of these QTLs in SCA patients with uncharacteristically high HbF are not known. We studied 20 African American SCA patients with markedly elevated HbF (mean 17.2%). They had significantly higher minor allele frequencies (MAF) in two HbF QTLs, BCL11A and HMIP, compared with those with low HbF. A 3-bp (TAC) deletion in complete linkage disequilibrium (LD) with the minor allele of rs9399137 in HMIP was also present significantly more often in these patients. To further explore other genetic loci that might be responsible for this high HbF, we sequenced a 14.1 kb DNA fragment between the Aγ(HBG1) and δ-globin genes (HBD). Thirty-eight SNPs were found. Four SNPs had significantly higher major allele frequencies in the unusually high HbF group. In silico analyses of these 4 polymorphisms predicted alteration in transcription factor binding sites in 3.

Hb Kenya is made up of two normal α‐globin chains and two Aγβ‐fusion globin chains. The latter are the product of an Aγβ‐hybrid globin gene formed as a result of misalignment during meiosis and nonhomologous crossing over. It is associated with a deletion of 22.7 kb including the δ‐globin gene, between the Aγ‐ and β‐globin genes. Hb Kenya is found in Kenyans and Ugandans. Heterozygotes have moderately increased Hb F, and this mutation has been known as an (Aγβ)+ hereditary persistence of fetal hemoglobin (HPFH). Compound heterozygotes for Hb Kenya/Hb S are thought to be asymptomatic, but reports of long term follow‐up of these patients are lacking. The correct identification of Hb Kenya is sometimes problematic. In cation exchange high performance liquid chromatography, Hb Kenya elutes in similar position as Hb A2, Hb Lepore, Hb E, and several other variant hemoglobins. Definitive diagnosis that is necessary for proper patient management is best done by DNA‐based gap‐PCR tests. Am. J. Hematol, 2009. © 2008 Wiley‐Liss, Inc.

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Key Clinical MessageWe present a case of isolated congenital hyposplenism that was discovered after the peripheral smear revealed Howell-Jolly bodies. This case serves as the basis for a review of hyposplenism for the general practitioner.

A 57-year-old man presented with generalized lymphadenopathy. Lymph node biopsy showed a vaguely nodular infiltrate of pleomorphic intermediate-sized lymphocytes (panels A and B, original magnification 320 and 3500, respectively; hematoxylin and eosin [H&E]-stained lymph node sections) that were CD20 1 (panel C, original magnification 3200), CD5 1 (panel D, original magnification 3200), CD23 2 , CD38 1 , SOX11 1 (panel H, original magnification 3200), and cyclin D1 2 (panel I, original magnification 3200). Cytogenetic analysis revealed an aneuploid karyotype and an absence of t(11;14)(q13; q32). IGH or CCND1 translocations were not detected by fluorescence in situ hybridization analysis. These findings were diagnostic of a cyclin D1 2 mantle cell lymphoma (MCL), a rare type of MCL often associated with upregulation of cyclin D2 or D3 (approximately 50% of cases harbor CCND2 translocations, and rare cases with CCND3 or MYCN translocations have been reported). Of note, approximately 50% of the neoplastic B cells showed cytoplasmic CD3e chain expression by immunohistochemistry (panel E, original magnification 3200; and panel F, CD3-brown and CD20-red dual stain, original magnification 3500). Flow cytometry also detected 1% surface CD3e 1 B cells. Besides CD3 and CD5, no other T-cell antigens were expressed (panel G, CD2 highlights a few scattered T cells; original magnification 3200). Polymerase chain reaction analyses for IGH and TRB gene rearrangement showed clonal and polyclonal products, respectively. Aberrant T-cell antigen expression has been described in a variety of B-cell non-Hodgkin lymphomas; however, this phenomenon is uncommon in MCL. Rare cases of MCL with aberrant CD8 or CD7 expression have been reported, but CD3e expression has not been described. The prognostic significance of T-cell antigen expression in MCL is not known. The patient was treated in a phase 1 study (ibrutinib and obinutuzumab), with response by positron emission tomography-computed tomography imaging.For additional images, visit the ASH IMAGE BANK, a reference and teaching tool that is continually updated with new atlas and case study images. For more information visit http://imagebank.hematology.org.

2068 HbF interferes with deoxygenated HbS polymerization, and is a major genetic modifier of sickle cell anemia severity. In this study, we attempted to identify genetic factors responsible for HbF production in a small group of African American sickle cell anemia patients who have markedly elevated HbF levels. Initially, patients with HbF of more than 11% as determined by HPLC were selected. The following were excluded: age less than 5; MCV greater than 100; presence of HPFH 1 and 2 based on specific gap-PCR tests; other β-globin gene deletions as determined by multiplex ligation-dependent probe amplification (MLPA). We further excluded rare HBG1 and 2 promoter HPFH mutations by nucleotide sequencing. In the end, a unique group of 20 patients were identified for further studies. Their mean age was 16.3 ± 8.3 years; Hb 9.0 ± 1.3 g/dL; MCV 87.9 ± 7.3 fL; and Hb F 17.2 ± 4.8% (range 11–29%). A control group of 30 African American patients were chosen. They had similar age, Hb, and MCV, but their HbF was 5.0 ± 2.5% (range 0.5–8.8%). These patients were examined for the 3 known major HbF quantitative trait loci: the Xmn1 restriction site C/T polymorphism at NT -158 upstream of HBG2; the BCL11A polymorphism on Chr2p16; the HBS1L-MYB intergenic polymorphism on Chr6q23. These 3 HbF quantitative trait loci collectively account for 20–50% of HbF variance in different populations. We found a significant association between high HbF and BCL11A and HBS1L-MYB intergenic region QTLs in these patients, but these account for only 20% of HbF variance (Table). These results were further validated in 590 patients of similar age from the Cooperative Study of Sickle Cell Disease, 57 patients with HbF 20.6 ± 8.2% and 533 patients with HbF 3.1 ± 1.5% (Table). To further explore other possible causes of elevated HbF, we sequenced 8.6 kb DNA fragment between HBG1 and HBD in 15 high HbF and 15 control patients. This DNA fragment includes the 7.2 kb Corfu deletion that is associated with elevated HbF levels and also binding sites for BCL11A. Twenty SNPs were found. The minor allele frequencies were consistently higher in the high HbF group, but the difference was found to be statistically significant only in 4 SNPs, 3 SNPs between positions 49213 and 49994 and 1 SNP at position 54541 (P = 0.001 to 0.04), suggesting that polymorphisms in this region might contribute to HbF expression in African American sickle cell anemia patients. The G→A polymorphism at position 49876 creates a C/EBP binding site which is not present in the major allele. The G→A polymorphism at position 49994 eliminates an AP-1 and NF-E2 binding sites, which are present in the major alleles. All 3 factors are erythroid transcription factors. The possible functional roles of these minor alleles found in significantly higher frequencies in the high HbF patients need to be further investigated. Disclosures: No relevant conflicts of interest to declare.

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