Etiology Myelofibrosis is a chronic myeloproliferative disorder characterized by bone marrow fibrosis and the development of extramedullary hematopoiesis. Myelofibrosis can occur as a primary disease entity (also termed idiopathic myelofibrosis or agnogenic myeloid metaplasia ) or can occur secondary to…
Etiology In 1925, Cooley and Lee described a series of patients suffering from severe anemia associated with splenomegaly and bone abnormalities. The name thalassemia , after fusion of the Greek words thalassa meaning “sea” and aima meaning “blood,” underlined the…
Etiology Sickle cell anemia, first described in a 20-year-old dental student from Grenada by Herrick in 1910, is the most common single-gene disorder in African Americans. Dr. Linus Pauling and his team identified the cause of SCA as a single…
Etiology Of all causes of hemophilia, types A and B are most associated with intraosseous and intraarticular bleeding. Hemophilia A (classic hemophilia) results from a deficiency of factor VIII. Hemophilia B (Christmas disease) is due to a functional deficiency of…
Ischemic bone lesions cover a wide spectrum of conditions with variable clinical and imaging findings in which oxygen delivery to the bone and marrow cells is impaired at least to some degree. Epiphyseal ischemic lesions have been more extensively investigated…
This chapter addresses general concepts on MRI of the bone marrow, with emphasis on common normal and abnormal marrow patterns. MRI plays a key role in marrow imaging because of its high sensitivity for detecting focal or diffuse alterations in…
Mycobacterial Infection In the 1950s, the atypical mycobacteria were recognized as human pathogens. They are morphologically similar to Mycobacterium tuberculosis but have different colonial characteristics. Because there is no evidence of human-to-human transmission, the atypical mycobacteria do not pose public…
Human immunodeficiency virus (HIV) infection is almost universally fatal if left untreated, leading to and being the etiologic agent of the acquired immunodeficiency syndrome (AIDS). The HIV epidemic is prevalent worldwide and is constantly evolving, being influenced by geographic, socioeconomic,…
Introduction Musculoskeletal infections in children are relatively common occurrences. However, in the pediatric population, such infections may produce nonspecific clinical signs and symptoms and can occur in the absence of clinically apparent features, such as swelling and erythema. This diagnostic…
Introduction Etiology Although hematogenous spread is the most common cause of osteomyelitis in most other areas of the body, contiguous spread and direct implantation are the most common in the foot and ankle. Direct implantation can occur from puncture wounds…