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14 results found

AIDS-defining illness

AIDS-defining illnesses are conditions that in the setting of a HIV infection confirm the diagnosis of AIDS, and do not commonly occur in immunocompetent individuals 2. According to the CDC surveillance case definition 1, they are: Infectious bacterial infections: multiple or recurrent candid...

CNS lymphoma

CNS lymphoma refers to the involvement of the central nervous system with lymphoma. It can be broadly divided into primary and secondary, with a number of special types of also recognised.  primary CNS lymphoma (PCNSL) intravascular lymphoma MALT lymphoma of the dura 5 secondary CNS lymphoma...

Diffuse T1 bone marrow signal loss

Diffuse T1 vertebral bone marrow signal loss has a number of causes. T1-weighted imaging without fat suppression is one of the most important sequences for distinguishing between normal and abnormal bone marrow. Given the homogeneity, this appearance can often be difficult to spot as abnormal.  ...


Erythrocytosis (or polycythaemia) is the presence of an excessive number of red blood cells in the circulation. It can be primary or arise secondarily to another pathology. Definition Absolute erythrocytosis is defined as a red cell mass which is >125% predicted for sex and age 2. Although th...

Haemolytic anaemia

Haemolytic anaemia is a form of anaemia where red blood cells (RBCs) are destroyed either intravascularly or extravascularly. Clinical presentation The patient presents with anaemia and jaundice. Diagnosis is based on several laboratory parameters 1: reticulocytosis increased unconjugated bi...


Haemosiderosis is a general term referring to the accumulation of haemosiderin, which particularly occurs in the reticuloendothelial system (RES) and does not cause organ damage. Pathology Some causes include: frequent transfusion  mainly depositional siderosis in RES if >40 units transfuse...

Hematopoietic stem cell transplantation (thoracic complications)

There are many thoracic complications that can occur following haematopoietic stem cell transplantation. These can precipitate during various stages following transplantation and can be either infectious or noninfectious. Complications Early pulmonary oedema engraftment syndrome diffuse alv...

Mediastinal lymph node enlargement

Mediastinal lymph node enlargement can occur from a wide range of pathologies. It may occur on its own or in association with other lung pathology. Terminology Although mediastinal lymphadenopathy is used interchangeably - by some - with "mediastinal lymph node enlargement", they are not synon...

PET-CT indications

PET-CT is a combination of cross-sectional anatomic information provided by CT and the metabolic information provided by positron emission tomography (PET). PET is most commonly performed with 2-[F-18]fluoro-2-deoxy-D-glucose (FDG). Fluorine-18 (F-18) is an unstable radioisotope and has a half-...

Pleural lymphoma

Pleural involvement with lymphoma can occur in two situations: primary pleural lymphoma primary effusion lymphoma secondary involvement of the pleura with lymphoma

Primary immunodeficiency states

Primary immunodeficiency states are heterogenous group of disorders that occur when there is an impairment of humoral or cell-mediated immunity in the absence of any recognised precipitating cause such as drug therapy or infective agent such as human immunodeficiency virus (HIV). Epidemiology ...

Splenic cyst

Splenic epithelial cysts, also referred as splenic epidermoid cysts or primary splenic cysts, are unilocular fluid lesions with thin and smooth walls and no enhancement. They represent ~20% of cysts found in the spleen, and are usually an innocuous incidental imaging finding. Note that most (~8...

Splenic pseudocyst

Splenic pseudocysts, also referred as secondary splenic cysts, are acquired cystic lesions not delineated by a true epithelial wall. They represent the majority of the splenic cystic lesions, corresponding to approximately 80% of them (c.f. splenic epithelial cysts). The main causes are:  splen...


Splenomegaly is a term which refers to enlargement of the spleen. The normal adult splenic length upper limit is usually around 12-15 cm. Also one should know how to calculate splenic index, volume and mass by CT and MR techniques. Massive splenomegaly is a term used when the spleen weighs >1000...

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