The value of radionuclide splenic scanning in the evaluation of asplenia in patients with heterotaxy

A global effort to dissect the human genetic basis of resistance to SARS-CoV-2 infection

SARS-CoV-2 infections display tremendous interindividual variability, ranging from asymptomatic infections to life-threatening disease. Inborn errors of, and autoantibodies directed against, type I interferons (IFNs) account for about 20% of critical COVID-19 cases among SARS-CoV-2-infected individuals. By contrast, the genetic and immunological determinants of resistance to infection per se remain unknown. Following the discovery that autosomal recessive deficiency in the DARC chemokine receptor confers resistance to Plasmodium vivax, autosomal recessive deficiencies of chemokine receptor 5 (CCR5) and the enzyme FUT2 were shown to underlie resistance to HIV-1 and noroviruses, respectively. Along the same lines, we propose a strategy for identifying, recruiting, and genetically analyzing individuals who are naturally resistant to SARS-CoV-2 infection.

Non-invasive evaluation of a liver mass in a patient post splenectomy

INTRODUCTION

Numerous conditions may cause liver lesions, solitary or multiple, benign or malignant. It can be crucial to establish the correct diagnosis. Splenosis is a rare condition that may result from the spillage of cells from the splenic pulp following abdominal trauma, accidental lesions to the spleen during operation or elective splenectomy. These splenic 'implants', which are often multiple, can be located anywhere in the peritoneal cavity, although they are most often found in the left upper quadrant of the abdomen. They may be confused with neoplasms or endometriosis, and may rarely be the cause of small bowel obstruction.

CASE PRESENTATION

A 35-year-old man presented with a hepatic mass, and malignancy was suspected. After extensive investigation, it was diagnosed as splenosis using Tc-99m-labelled heat-denaturated red blood cells scintigraphy, without the need for liver biopsy. We consider this the most effective method for diagnosing splenosis.

CONCLUSION

When splenosis is suspected, Tc-99m-labelled heat-denaturated red blood cells scintigraphy can be used to confirm the diagnosis, and may avoid invasive investigation.

Radiologic Considerations in Heterotaxy: The Need for Detailed Anatomic Evaluation

So-called "heterotaxy" is a laterality defect characterized by isomerism of the thoracic organs and random arrangement of the abdominal organs. These findings go beyond anatomic curiosity and have functional implications. It is, thus, of the utmost importance to be able to properly identify these findings. Radiologic studies can be invaluable in determining anomalies in the central nervous, pulmonary, cardiovascular, gastrointestinal, genitourinary, and immunologic systems in patients with isomerism. Here, we review findings associated with isomerism and their importance in the setting of isomerism with the aim of ensuring that radiologists effectively describe findings in these patients and that cardiologists understand the wide variety of congenital malformations that may be present.

A pattern-oriented approach to splenic imaging in infants and children

The spleen in infants and children is commonly involved in a variety of pathologic processes. Some of these processes cause isolated splenic disease, whereas others involve the spleen as part of a systemic illness. To facilitate differential diagnosis of splenic abnormalities, a pattern-oriented approach to the imaging evaluation of the pediatric spleen was developed. With this approach, splenic anomalies are categorized as anomalies of splenic shape (clefts, notches, lobules), location (eg, wandering spleen), number (polysplenia, asplenia), or size (splenomegaly, splenic atrophy); solitary lesions (eg, cysts, lymphangiomas, hemangiomas, hamartomas); multiple focal lesions (eg, trauma, infection and inflammation, neoplasms, storage disorders); and diffuse disease without focal lesions (eg, infarction, heavy metal deposition, hemangioendotheliomas, peliosis). A variety of imaging modalities can be used in splenic assessment, including computed tomography, magnetic resonance imaging, ultrasound, and technetium-99m scintigraphy. The imaging appearance of the pediatric spleen depends on the patient's age and the modality used; however, familiarity with the spectrum of radiologic patterns of splenic involvement will facilitate correct diagnosis and prompt treatment.