MRI features of intrahepatic extramedullary haematopoiesis in sickle cell anaemia

The liver in sickle cell disease

Liver involvement in SCD patients is frequent but often misdiagnosed or underestimated, except in case of advanced liver diseases. Because of so far poorly recognized forms of chronic SCD-related vascular injury that can silently evolved towards end stages or facilitate ACLF, any persisting liver function tests abnormalities should be carefully investigated, following the above proposed algorithm. Work up and management must be considered multidisciplinary in relationship with a Hepatologist. Early SCD hepatopathy should prompt revision of SCD management to prevent further liver injury and decompensation, discussing transfusion exchanges and hydro urea when not yet initiated, and control for any cofactor of liver injury. The role of HSCT in early SCD hepatopathies also deserves evaluation. In advanced SCD hepatopathies, liver transplantation, which has been rarely performed so far, is the only therapeutic option associated with improved survival. It should definitely be discussed- either electively in case of decompensation in SCD cirrhosis or jaundice/recurrent cholangitis in cholestatic diseases, with excellent outcome, - or emergently in case of ALF or ACLF with more mitigate results. To improve knowledge and management of SCD liver diseases, creation of national and international registries, as well as longitudinal observational cohorts are encouraged.

Magnetic resonance imaging features of intrahepatic extramedullary hematopoiesis: Three case reports

BACKGROUND

Extramedullary hematopoiesis rarely occurs within the liver alone, and is easily misdiagnosed. The radiological literature on this disease is exclusively case reports. There is a paucity of literature on the role of magnetic resonance imaging (MRI). The most common imaging modalities used are computed tomography and ultrasound. This report aims to provide more data on the appearance of extramedullary hematopoiesis using MRI to help radiologists establish the diagnosis.

CASE SUMMARY

Three patients (one male and two females) were incidentally found to have a hepatic mass or nodule, without hepatomegaly or splenomegaly. Laboratory tests including liver function, serum hepatic tumor markers, and hepatitis serologic markers were normal. On MRI scans, all lesions showed lower signal intensity on in-phase images than on out-phase images. One case showed changes in signal intensity on T2 weighted images (WI) and diffusion WI, which shifted from hyperintensity to hypointensity with size enlargement between two rounds of imaging examination. These lesions exhibited different enhancement patterns on dynamic contrast enhancement series.

CONCLUSION

The MRI signal change and in-/out-phase image might provide useful information and help radiologists establish the diagnosis of intrahepatic extramedullary hematopoiesis.

MRI Appearance of Focal Lesions in Liver Iron Overload

Liver iron overload is defined as an accumulation of the chemical element Fe in the hepatic parenchyma that exceeds the normal storage. When iron accumulates, it can be toxic for the liver by producing inflammation and cell damage. This can potentially lead to cirrhosis and hepatocellular carcinoma, as well as to other liver lesions depending on the underlying condition associated to liver iron overload. The correct assessment of liver iron storage is pivotal to drive the best treatment and prevent complication. Nowadays, magnetic resonance imaging (MRI) is the best non-invasive modality to detect and quantify liver iron overload. However, due to its superparamagnetic properties, iron provides a natural source of contrast enhancement that can make challenging the differential diagnosis between different focal liver lesions (FLLs). To date, a fully comprehensive description of MRI features of liver lesions commonly found in iron-overloaded liver is lacking in the literature. Through an extensive review of the published literature, we aim to summarize the MRI signal intensity and enhancement pattern of the most common FLLs that can occur in liver iron overload.

Extra-Medullary Hematopoiesis in Sickle Cell Disease Presenting as a Right Adrenal Mass

Extramedullary hematopoiesis can occur during normal fetal development or as a compensatory mechanism in chronic anemia when the primary sites of hematopoiesis fail. When it occurs, it is mostly seen in sites such as the liver, spleen, and lymph nodes. Extramedullary hematopoiesis is seen in patients with abnormal morphology of red blood cells like thalassemia and abnormal red blood cell shape like hereditary spherocytosis. The incidence of extramedullary hematopoiesis in sickle cell disease is very rare. We report a case of focal adrenal extramedullary hematopoiesis in a 21-year-old patient with sickle cell disease who presented with pain in the right thorax. A retroperitoneal mass was seen in the MRI of the abdomen of the patient suggestive of extramedullary hematopoiesis. Our case highlights the importance of physician awareness of this rare pathology for proper diagnosis and management.

Extramedullary haematopoiesis presenting as a periportal mass

Extramedullary haematopoiesis (EMH) is defined as haematopoiesis occurring in organs outside the bone marrow. The liver is one of the rare sites of EMH, and to the best of our knowledge, a few cases of adult EMH of the liver have been reported in the last 20 years. Here, we reported the case of a 68-year-old man with a known history of myelofibrosis presented with vague abdominal pain. An abdominal CT scan showed a hypoattenuating periportal mass encasing the portal vein. The final diagnosis of EMH was made through the histopathological examination. This is a rare presentation of EMH, which may be easily mistaken for other pathologies such as metastases. Familiarity with this type of presentation aids in correctly diagnosing it in an appropriate clinical setting.

Primary myelofibrosis: spectrum of imaging features and disease-related complications

Primary myelofibrosis is a chronic clonal stem cell disorder that results in a build-up of marrow fibrosis and dysfunction, hypermetabolic states, and myeloid metaplasia. The clinical and radiological consequences can be quite diverse and range from the manifestations of osteosclerosis and extramedullary haematopoiesis to thrombohaemorrhagic complications from haemostatic dysfunction. In addition, there is the challenge of identifying less well-recognised sites of extramedullary haematopoiesis and their site-specific complications. The intent of this article is to illustrate the spectrum of primary myelofibrosis as declared though multimodality imaging, with examples of both common and rarer disease manifestations.

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.

Hepatic nodule: a case of primary myelofibrosis

Primary myelofibrosis is one of the entities that may manifest with lesions of extramedullary haematopoiesis, especially in spleen and liver. The authors report a case of primary myelofibrosis presenting incidentally as an intrahepatic focal lesion of extramedullary haematopoiesis, a rare occurrence that highlights the challenge of hepatic nodule differential diagnosis, and allows reflection about the diagnostic criteria and prognostic factors of this myeloproliferative disease.

Uterine extramedullary hematopoiesis: what is the clinical significance?

Extramedullary hematopoiesis (EMH) represents abnormal development and growth of hematopoietic tissue outside the bone marrow. Recent studies have shown its association with myelofibrosis and myeloid metaplasia, chronic myeloproliferative disorders, and other hematologic malignancies in up to two-thirds of the cases. Eleven cases of uterine EMH (UEMH) have been reported earlier; of these half had a concurrent, or subsequently developed a clinically significant hematologic disorder. We studied a larger group of patients with UEMH to understand the relationship with hematologic disorders. Cases diagnosed as UEMH between 1995 and 2007 were retrieved from our files (n=20). UEMH was confirmed in all 20 cases. Eighteen cases were located in the fundus including 5 in endometrial polyps and 5 in leiomyomas. Two foci were located within the cervix. The erythroid lineage was present in all foci; 35% also had myeloid precursors, and 2% had megakaryocytes. Twelve of 20 patients had underlying anemia (mean Hgb of 11 mg/dL, range: 5.5 to 15.7 mg/dL). No preexisting hematologic malignancy was identified in any of the patients. Follow-up information was available on 17 patients (mean: 2.88 yr; range: 0.2 to 9 yr). None of the patients developed a significant hematologic disorder other than anemia during follow-up. On the basis of our study, UEMH is frequently associated with chronic anemia. In comparison with existing literature suggesting a strong link between UEMH and hematopoietic disorders, our findings suggest that UEMH is rarely associated with serious underlying hematologic conditions and therefore does not warrant extensive hematologic workup.

CT and MR findings in extramedullary haematopoiesis with biliary system encasement: a case report

Extramedullary haematopoiesis is the production of blood elements outside the bone marrow cavity. In our case computed tomography and magnetic resonance imaging revealed the presence of a rare localization of extramedullary haematopoiesis with encasement of the biliary system in a 59 years-old male Caucasian patient, with chronic myelofibrosis and hepatic failure's symptomatology. Computed tomography detected the presence of homogeneous hypodense tissue around intra-hepatic bile ducts with minimal contrast enhancement, strongly suggestive for extramedullary haematopoiesis. Magnetic resonance confirmed the presence of a solid tissue surrounding the biliary tree, showing late enhancement after gadolinium administration suggestive for non-active lesion of extramedullary haematopoiesis. Final diagnosis was established by percutaneous biopsy.

Intrahepatic extramedullary hematopoiesis mimicking a hypervascular hepatic neoplasm on dynamic- and SPIO-enhanced MRI

We present a rare case of a focal intrahepatic extramedullary hematopoiesis (EMH) that mimicked a hypervascular hepatic neoplasm in a 33-year-old woman with idiopathic myelofibrosis. The lesion showed homogeneous and persistent enhancement on both contrast-enhanced CT and gadolinium-enhanced dynamic MR imaging. The lesion did not demonstrate an apparent signal drop on a T2^*-weighted sequence following administration of a superparamagnetic iron-oxide agent (SHU 555A). A hepatocellular adenoma was the initial radiological diagnosis. To the best of our knowledge, this is the first report of a histopathologically proven intrahepatic EMH evaluated with dynamic- and SPIO-enhanced MRI.