Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_2603_Библиотеки_им_академика_М_И_Перельмана
.pdf
350
https://t.me/medicina_free
Chapter 9 · Hematology
ab
9
. Fig. 9.1.2 Axial T1W ( a ) and T2W ( b ) brain MRI show a hypointense rim that surrounds the pons ( arrowhead ) due to super cial brain
siderosis
Further Reading
9.2 β-Thalassemia Major (Cooley’s Anemia)
Argyropoulou MI, etal. MRI evaluation of tissue iron burden
in patients with β-thalassemia major. Pediatr Radiol.
2007a;37:1191–200.
Bonetti MG, et al. Hepatic iron overload in thalassemic
patients: proposal and validation of an MRI method of
assessment. Pediatr Radiol. 1996;26:650–6.
Brasch RC, et al. Magnetic resonance imaging of transfu-
sional hemosiderosis complicating thalassemia major.
Radiology. 1984;150:767–71.
Chen CH, etal. Idiopathic pulmonary hemosiderosis: favor-
able response to corticosteroid. J Chin Med Assoc.
2008;71:421–4.
Deugnier Y, etal. Iron and the liver: update 2008. J Hepatol.
2008;48:S113–23.
Flyer MA, etal. Transfusional hemosiderosis in sickle cell
anemia: another cause of an echogenic pancreas. Pediatr
Radiol. 1993;23:140–2.
Koçak R, etal. e liver siderosis in beta-thalassemia interme-
dia and hemoglobin disease. J Islamic Acad Sci. 1993;6:42–5.
Positano V, etal. Improved T2* assessment in liver iron over-
load by magnetic resonance imaging. Magn Reson
Imaging. 2008a;27:188–97. doi:10.1016/j.mri.2008.06.004.
Rosenberg W.Haemochromatosis Med. 2007;35:89–92.
Rosenberg W, et al. Haemochromatosis. Medicine.
2002;30:63–4.
β-thalassemia major is a hereditary hemolytic anemia, char-
acterized by de ciency in the hemoglobin beta chain synthesis. Patients with β-thalassemia major are prone to repeated
attacks of intravascular hemolysis that requires repeated hospitalization and blood transfusions.
Patients with β-thalassemia major present with microcytic hypochromic anemia with signs of fatigue and cardiac
tachycardia.
Repeated blood transfusion predisposes to hemosiderosis
and tissue iron burden, which is the most severe complication of this disease. Hemosiderosis causes cardiomyopathy,
hepatic failure, hypogonadism (pituitary siderosis), and
endocrinal abnormalities. Bronze diabetes is a term used to
describe diabetes mellitus induced in a patient with thalassemia due to pancreatic hemosiderosis. e term “bronze”
refers to skin darkening and hyperpigmentation that is seen
in patients with chronic thalassemia, due to deposition of
hemosiderin in the subcutaneous tissues. Hypoparathyroidism
is one of the most important endocrinal complications of
thalassemia.
Extramedullary hematopoiesis is commonly observed in
these patients due to increased body demands. Extramedullary
hematopoiesis can be appreciated on plain radiographs as
abnormally widened, at bones.
9.2 · β-Thalassemia Major (Cooley’s Anemia)
https://t.me/medicina_free
Within the past few years, MRI has emerged as a powerful
diagnostic tool to detect hemosiderosis through the body.
Techniques for tissue iron burden quanti cation are well
established for the liver and the heart. Early treatment with
chelating agents (e.g., desferrioxamine) reduces the severity
of the iron burden complication. MRI iron burden quanti cation helps in monitoring chelation therapy.
Signs on Skeletal Radiograph
5 Skull hair - on - end appearance : increase of the
trabeculae within the skull bones, due to
extramedullary hematopoiesis that widens the
calvarial flat bones (. Fig. 9.2.3 )
5 Square-shaped metacarpals and thin cortex, due
to bone marrow proliferation (. Fig. 9.2.4 )
5 Dilated ribs due to extramedullary hematopoiesis
(. Fig. 9.2.5 )
5 Splaying of the femoral metaphysis (Erlenmeyer
flask deformity)
351
9
. Fig. 9.2.3 A plain radiograph of the lateral skull of a patient
with thalassemia shows hair-on-end-appearance
. Fig. 9.2.5 AP plain radiograph shows expansion of the ribs
due to extramedullary hematopoiesis ( arrowheads )
Signs on CT
5 Hepatic hemosiderosis is one of the main causes of
high-density liver on nonenhanced CT images
(. Fig. 9.2.6 ). The liver density will show high HU
difference compared to the muscles and the
spleen, with a range of 80–140 HU.Other causes of
. Fig. 9.2.4 A plain radiograph of the hand shows squaring
and expansion of the phalanges due to extramedullary
hematopoiesis in a young patient with thalassemia
. Fig. 9.2.6 Axial nonenhanced CT of the abdomen shows
high-density liver
352
https://t.me/medicina_free
Chapter 9 · Hematology
nonenhanced CT high-density liver are Wilson’s
disease due to copper deposition, and hepatic
iodine deposition, rarely seen in amiodarone
toxicity.
5 Hepatosplenomegaly often occurs due to
extramedullary hematopoiesis (. Fig. 9.2.7 ).
5 Thoracic paraspinal masses and enlarged lymph
nodes may be seen due to extramedullary
hematopoiesis (. Fig. 9.2.8 ).
5 Cerebral calcification may be seen due to
hypoparathyroidism in thalassemia patients.
Patients may uncommonly show bilateral
symmetrical basal ganglia calcifications
(. Fig. 9.2.9 ).
9
. Fig. 9.2.9 Axial nonenhanced brain CT shows bilateral,
almost symmetrical, basal ganglia calci cations
. Fig. 9.2.7 Axial nonenhanced CT of the abdomen shows
hepatomegaly with left liver lobe hypertrophy
. Fig. 9.2.8 Axial nonenhanced CT illustration of the thorax
shows bilateral paraspinal masses due to extramedullary
hematopoiesis ( arrowheads ). These masses can be easily
mistaken for tumors. Other signs of extramedullary
hematopoiesis support the diagnosis
Signs on MRI
5 Iron burden quantification is done with the use of
T2* sequences (. Fig. 9.2.10 ). The
superparamagnetic properties of the iron
deposited within the tissues cause decreased
signal intensity of the tissues containing iron. As a
result, hepatic parenchyma, splenic parenchyma,
and cardiac muscles with siderosis appear
hypointense compared to normal parenchyma.
5 In mild liver siderosis, the liver appears
hypointense only on T2* images, compared to
muscles. In moderate to severe cases, the liver
appears hypointense to spleen and muscles in all
sequences. The spleen shows almost the same
picture as the liver, due to iron deposition. In
primary hemochromatosis, only the liver shows
decreased signal intensity, while the spleen is
spared.
5 In the heart, iron overload appears as a dark ring
on T1W, T2W, and T2* images.
5 In bronze diabetes, the pancreas and sometimes
the adrenals show low signal intensity due to iron
deposition.
5 In hypogonadism and signs of pituitary failure, the
anterior pituitary shows low signal intensity on
T1W, T2W, and T2* images, reflecting severe iron
deposition.
9.3 · Sickle Cell Disease
https://t.me/medicina_free
353
9
. Fig. 9.2.10 Axial abdomen section in di erent sequences illustrates the method of liver iron burden quanti cation in the liver and the
paraspinal muscles
Further Reading
Argyropoulou MI, etal. MRI evaluation of tissue iron burden
in patients with β-thalassemia major. Pediatr Radiol.
2007b;37:1191–200.
Drakonaski E, et al. Adrenal glands in beta-thalassemia
major: magnetic resonance (MR) imaging features and
correlation with iron store. Eur Radiol. 2005;15:2462–8.
Karimi M, etal. Prevalence of hepatosplenomegaly in beta
thalassemia minor subjects in Iran. Eur J Radiol.
2007;59:120–2. doi:10.1016/j.ejrad.2007.09.027.
Karimi M, etal. Hypoparathyroidism and intracerebral calci-
cation in patients with beta-thalassemia major. Eur J
Radiol. 2008;70:481–4. doi:10.1016/j.ejrad.2008.02.003.
Lal A, etal. Focal splenic lesions as a cause of extramedullary
hematopoiesis in a case of thalassemia. Eur J Radiol Extra.
2008;68:e125–7.
Louis CK.Low growth of children with β-thalassemia major.
Indian J Pediatr. 2005;72:159–64.
Mavrogeni S, etal. Magnetic resonance evaluation of liver and
myocardium iron deposition in thalassemia intermedia
and β-thalassemia major. Int J Cardiovasc Imaging.
2008;24:849–54.
Papakonstantinou O, etal. MR imaging of spleen in beta-
thalassemia major. Abdom Imaging. 2006;40:2777–82.
doi:10.1007/s00261.006.9138-4.
Positano V, etal. Improved T2* assessment in liver iron over-
load by magnetic resonance imaging. Magn Reson
Imaging. 2008b;27:188–97. doi:10.1016/j.mri.2008.06.004.
9.3 Sickle Cell Disease
Sickle cell disease (SCD) is an autosomal recessive genetic
disorder, characterized by episodic attacks of hemolytic anemia and vaso-occlusive attacks due to “sickling” of the red
blood cells (RBCs) under certain body conditions that
include dehydration, metabolic acidosis, and low oxygen
saturation.
SCD results from abnormal production of hemoglobin
(Hb-S). Sickle cell patients are homozygous (HbSS), while
354
https://t.me/medicina_free
Chapter 9 · Hematology
heterozygous patients have “sickle cell trait.” SCD can also
arise when Hb-S is combined with abnormal hemoglobin
(e.g., Hb-S-thalassemia). Hb-S di ers from the normal Hb-A
only in the substitution of valine for glutamic acid in the
sixth position of the β chain.
In SCD, the normal, discoid RBCs shape is transformed
into a sickle-shaped, sticky mass during deoxygenation.
ese sickle cells can stick together, forming a hard mass that
may lead to embolization and arterial infarction in di erent
parts of the body.
Approximately 50 % of patients with SCD experience
painful crises by the age of 5 years. Patients with sickle cell
disease have natural protection against malaria; the reasons
are unknown.
The Lungs inSCD
Patients with SCD have greater susceptibility to pneumonia
9
(100 times more than other children), due to impaired
immune status. e infective agents are commonly
Streptococcus pneumoniae , Haemophilus in uenzae , and
Salmonella. Acute chest syndrome (ACS) is a term used to
describe newly developed pulmonary consolidation, accompanied by fever, chest pain, dyspnea, and cough. e underlying cause is known and presumably due to fat emboli. ACS is
the second most common cause for hospital admissions in
children with SCD, a er painful crises. ACS is also seen in up
to 10 % of SCD patients a er general anesthesia.
The Skeletal System inSCD
Skeletal manifestations in SCD range between vaso-occlusive
crises, extramedullary hematopoiesis, osteomyelitis, and vertebral changes. Bone infarction is the most common cause of
pain crises in SCD.However, silent infarctions do exist in
patients with SCD. ere are four zones seen in bone infarction by histology: the zone of cell death located in the center,
the zone of ischemic tissue, the zone of hyperemia, and the
outer zone of normal bony tissue.
Osteomyelitis means in ammation of the bone and the
bone marrow. Osteomyelitis is commonly caused by
Salmonella infection in sickle cell patients. In nonsickle cell
patients, the most common cause of osteomyelitis is
Staphylococcus aureus .
patients experience this syndrome before 4 years of age, and
the disease has not been reported beyond 7 years. e condition is self-limiting, with a duration that varies from a week
to a month.
What Is the Difference Between Osteonecrosis ,
Avascular Necrosis , and Bone Infarction ?
Osteonecrosis is ischemic death of the bone and bone marrow.
Avascular necrosis is osteonecrosis that occurs in the
epiphyses.
Bone infarction is osteonecrosis that occurs in the metaphy-
ses or diaphyses.
The Brain inSCD
In SCD, the brain may be damaged due to infarction from
sickle cell emboli or from vasculitis. Up to 25 % of patients
with SCD will have a neurological complication over their
lifetime; 11 % of these complications will occur by the age of
20 years. Silent infarction is de ned as MRI manifestation of
cerebral infarction in the absence of clinical symptoms and
occurs in up to 22 % of patients with SCD.
The Spleen inSCD
Multiple spleen infarctions due to vaso-occlusive crises are a
very common feature in SCD. With time, the spleen is
replaced by brous tissue and by calcium and hemosiderin
deposition (called autosplenectomy ). Up to 94 % of patients
are asplenic by the age of 5 years.
Patients with splenectomy are susceptible to infection
with Staphylococcus pneumoniae , Salmonella , and
Haemophilus in uenzae . Pneumococcal vaccine is o en
started between 2 and 5 years of age.
Sequestration syndrome is another condition that com-
monly occurs in SCD patients, characterized by rapid pooling of the blood within the spleen, resulting in intravascular
volume depletion and dropping hematocrit levels. When the
sequestration is severe, patients present with abdominal fullness, thirst, tachycardia, and tachypnea that may rapidly
progress into circulatory collapse. Up to 30 % of patients
experience sequestration syndrome between the ages of 6
months and 3 years.
D i erential Diagnoses andRelated Diseases
Hand – foot syndrome is an uncommon disease seen in sickle
cell patients in up to 20 % of cases, characterized by bilateral
in ammation and swelling of the ngers and toes (dactylitis).
Patients present with fever, bilateral digital swelling in the
hands and feet, leukocytosis, and pain. It can be mistaken for
osteomyelitis in the initial presentation. Osteomyelitis is
uncommonly known to cause bilateral infection in the hands
and feet simultaneously. Also, osteomyelitis o en involves the
long bones, not the small bones of the hands and feet. Most
Signs on Chest Radiograph
5 Pneumonia is seen as areas of patchy lung
infiltration with air bronchogram. The airspace
disease may be lobar or diffuse.
5 Acute chest syndrome is seen as single or multiple
patchy areas of airspace disease, often confined to
the middle and lower lobes. Up to 60 % of patients
with ACS show normal chest radiograph.
9.3 · Sickle Cell Disease
https://t.me/medicina_free
355
9
Signs on Skeletal Radiograph
5 Bone infarction : it is seen as a radiolucent area
surrounded by the sclerotic rim, typically in the
epiphyses and the medullary cavity (. Fig. 9.3.11 ).
Later, sclerosis of the infarcted areas causes the
appearance of dense bone within the affected
bone (bone-in-bone appearance).
5 H - shaped vertebra : there is central end plate
depression, with sparing of the anterior and
posterior margins due to previous infarctions of
vertebral bodies. An H-shaped vertebra is a
characteristic sign of SCD (. Fig. 9.3.12 ).
5 Expansion of the diploic medullary spaces of the
skull due to increased hematopoietic demands
(hair-on-end appearance).
5 Osteomyelitis : the early changes seen
radiographically are soft-tissue swelling or a mass,
occasionally gas, periosteal reaction, and (later)
cortical destruction. There are usually no signs on
plain radiograph in the first 2 weeks of infection.
The cortical destruction first appears as small
lucent holes (permeative destruction), followed
later by larger coalescent lesions (moth-eating
destruction). Osteomyelitis can be difficult to
differentiate from infarction.
5 Hand – foot syndrome : the typical signs of dactylitis
include soft-tissue swelling of the digits, cortical
thinning, multiple intramedullary radiolucent
deposits, and thick periosteal new bone formation
(. Fig. 9.3.13 ). The radiological manifestations are
completely reversible after 8 months.
5 Protrusio acetabuli: it may occur in SCD in up to
20 % of cases.
. Fig. 9.3.11 Plain radiograph of the distal femur metaphysis
shows radiolucent areas surrounded by sclerotic rims
( arrowheads ) due to old bone infarction in a patient with sickle
cell disease (SCD)
. Fig. 9.3.12 Lateral vertebral plain radiograph of a patient
with SCD shows H-shaped thoracic vertebra
356
https://t.me/medicina_free
Chapter 9 · Hematology
9
. Fig. 9.3.13 Plain radiograph of both hands in a sickle-cell patient shows thick periosteal new bone formation a ecting the fth and
fourth right metacarpal bones and the fth left metacarpal bone ( arrowheads ), changes indicating hand-foot syndrome
Signs on Chest CT
Extramedullary hematopoiesis may be found as bilateral
or unilateral, smooth or lobulated paraspinal masses in
the lower thoracic spine, without vertebral erosions.
History of hematological disease is the key diagnosis to
di erentiate these masses from tumors.
Signs on Abdominal CT
5 Spleen infarction is seen on noncontrast-enhanced
images as a hypodense, wedge-shaped area,
which typically starts from the periphery toward
the center, with no contrast enhancement
(. Fig. 9.3.14 ).
5 Sequestration syndrome is seen as splenomegaly
with hypodense peripheral areas.
. Fig. 9.3.14 Axial abdominal postcontrast CT shows
multiple hypodense wedge-shaped areas within the spleen, due
to multiple areas of infarction
9.4 · Pernicious Anemia
https://t.me/medicina_free
Signs on Skeletal MRI
5 MRI is important in the early detection of bone
infarction. On T2W images, there is an area
surrounded by a hyperintense line and an outer
hypointense line ( double - line sign ). The
high-intensity line represents the zone of
hyperemia. Double-line sign is found in up to 80 %
of cases of bone infarction.
5 The yellow marrow is made of 80 % fat, 15 % water,
and 5 % proteins. On MRI, it gives high signal in
T1W images. In contrast, the red marrow is made
of 40 % fat, 40 % water, and 20 % proteins. This
high water content gives low signal in both T1W
and T2W images. Extracellular hematopoiesis,
especially within the vertebrae, can be suggested
by observation of the intervertebral disk signal.
Normally, the vertebral bodies have higher signals
than the intervertebral disks on T1W images, due
to the fatty marrow. In extracellular hematopoiesis,
the yellow marrow is reconverted into red marrow
due to the hematopoietic demands, resulting in
low signal intensity of the vertebral bodies
compared to the intervertebral disks on T1W
images ( high - density disk sign ). This sign is
observed in any disease with bone marrow
infiltration.
Signs on Brain MRI
5 Silent infarction is detected as a high signal
intensity lesion within the white matter on T2W or
FLAIR images.
5 Moyamoya disease is detected by its classical “puff
of smoke” appearance on MR angiography and
occlusion of the ipsilateral internal carotid artery.
Further Reading
Babhulkar SS, etal. e hand-foot syndrome in sickle-cell
haemoglobinopathy. J Bone Joint Surg (Br). 1995;77B:310–2.
Ejindu VG, etal. Musculoskeletal manifestations of sickle cell
disease. Radiographics. 2007;27:1005–21.
Janet Watson R, etal. e hand-foot syndrome in sickle-cell
disease in young children. Pediatrics. 1963;31:975–82.
Lonergan GJ, et al. Sickle cell anemia. Radiographics.
2001;21:971–94.
Lukens JN.Sickle cell disease. Dis Mon. 1981;27:1–56.
Lukens JN.Sickle cell disease. Dis Mon. 1981;27:1–56.
Schatz J, etal. Sickle cell disease as a neurodevelopmental dis-
order. Ment Retard Dev Disabil Res Rev. 2006;12:200–7.
357
9.4 Pernicious Anemia
Pernicious anemia (PA) is a disease characterized by the
development of megaloblastic anemia due to destruction of
the gastric parietal cells. Megaloblastic anemias are a sub-
group of macrocystic anemias (large volume red blood cells),
which most commonly arise due to vitamin B
and folate
12
de ciencies.
Normally, the parietal cells in the gastric mucosa secrete an
intrinsic factor, which is important for absorption of vitamin
from the gastrointestinal tract. e fundus of the stomach
B
12
contains parietal cells, the body contains the cells responsible
for the secretion of pepsin and hydrochloric acid, and the
antrum contains G cells. Patients with PA develop antigastric
parietal cells (GPC) and anti-intrinsic factor antibodies (gastric parietal cells antibodies, or AGPA), which attack the parietal cells and cause autoimmune gastritis. Destruction of the
gastric parietal cells leads to gastric mucosal atrophy and compromises the production of the intrinsic factor. Moreover, the
atrophic gastritis also compromises the gastric acid pump,
leading to de ciency in the secretion of gastric acids (hypo- or
achlorhydria). Loss of vitamin B
causes defective synthesis of
12
the bone marrow cellular activities, leading to the development of megaloblastic erythropoiesis and macrocytic anemia.
Chronic gastritis induces enterochroma n-like cell
hyperplasia, which may result in the development of gastric
carcinoid tumors. Compared to the general population, gastric adenocarcinoma is 3–5 times more frequent among
patients with PA. e activity of natural killer cells, which
participate in immunosurveillance against tumor dissemination, is believed to be compromised in patients with PA.
Atrophic gastritis is divided into two types. Atrophic gastritis type (a) is characterized by mucosal atrophy a ecting
the fundus and the body of the stomach, with antral sparing.
In contrast, atrophic gastritis type (b) is characterized by
antral mucosal atrophy, with limited involvement of the fundus and body.
AGPAs are found in 20 % of patients with diabetes mellitus type 1 (DMT1). Researchers suggest that patients with
DMT1 should be regularly screened for atrophic gastritis. PA
is rare found in the general population, with an incidence of
0.1–2 % of the population. On the other hand, patients with
DMT1 have a threefold increased incidence of PA, with a
prevalence of 2.5–4 %.
Diagnosis is con rmed by detecting AGPA levels in the
serum by the Schilling test.
Signs on Barium Meal
5 In a normal double-contrast barium meal
examination, the stomach mucosal folds (rugae)
are observed arranged in an irregular fashion
through the fundus, body, and antrum
(. Fig. 9.4.15 ). At the lesser curvature near the
pylorus, the mucosal folds become longitudinal
9
358
https://t.me/medicina_free
Chapter 9 · Hematology
and are known as magenstrasse. Area gastrica is an
area of nodular mucosal elevation located near the
antrum (. Fig. 9.4.16 ).
5 In Pernicious anemia, there is a tubular-shaped
fundus <8cm in diameter absent or reduced
amount of the normal gastric rugae in the fundus
of the body (bald fundus) and small or absent area
gastrica (. Fig. 9.4.17 ) .
9
. Fig. 9.4.17 Double-contrast barium meal of a patient with
pernicious anemia demonstrates severe atrophic gastritis with
loss of the normal mucosal folds. Compare this image with
. Fig. 9.4.15
. Fig. 9.4.15 Double-contrast barium meal shows the normal
con guration of the stomach with the mucosal folds (rugae)
nicely demonstrated
. Fig. 9.4.16 Double-contrast barium meal shows area
gastrica, seen as an area with nodular mucosal pattern
Further Reading
Levine MS, et al. Atrophic gastritis in pernicious anemia:
diagnosis by double-contrast radiography. Gastrointest
Radiol. 1989;14:215–9.
Tzellos TG, etal. Pernicious anemia in a patient with type 1
diabetes mellitus and alopecia areata universalis. J
Diabetes Complications. 2009;23:434–7. doi:10.1016/j.
jdiacomp.2008.o5.003.
Vargas JA, etal. Natural killer cell activity in patients with
pernicious anemia. Dig Dis Sci. 1995;40:1538–41.
Varis K, etal. An appraisal of tests for severe atrophic gastritis
in relatives of patients with pernicious anemia. Dig Dis
Sci. 1979;24:187–91.
Wickramasinghe SN. Diagnosis of megaloblastic anemias.
Blood Rev. 2006;20:299–318.
9.5 Hemophilia
Hemophilia is a rare, chronic X-linked genetic disease, characterized by the body’s inability to form clotting factors necessary for the blood clotting cascade to occur, resulting in a
tendency toward spontaneous bleeding or bleeding a er
minor body trauma.
e word hemo means bleeding, and the word philia
means tendency toward something. Patients with hemophilia
9.5 · Hemophilia
https://t.me/medicina_free
359
9
have a tendency for slow bleeding, at a constant rate and
without clotting, into muscles, joint spaces, and body cavities.
Blood clotting is a complicated process that involves three
primary steps. e rst step involves immediate constriction
of the blood vessels in the area of injury. e second step
involves the formation of a platelet plug that stops the bleeding. e third step involves the activation of 12 clotting factors (identi ed by Roman numerals) that transform the
platelet plug into a more stable clot by transforming it into
brin. e activation of clotting factors is referred to as the
“clotting cascade,” because each factor stimulates the next
factor in the series, until the formation of the brin. De ciency
of one factor will stop the cascade, and a stable clot will not
form.
ere are three types of hemophilia:
5 Hemophilia A results from de ciency of clotting factor
VIII, and it is the most common form of hemophilia
(80 %). e incidence is 1:10,000 people.
5 Hemophilia B ( Christmas disease ) results from de ciency
of clotting factor IX and constitutes up to 23 % of
hemophilia cases. e disease was named a er a young
boy, Stephen Christmas, who was the rst patient
identi ed with this disease. e incidence is 1:40,000
people.
5 Hemophilia C results from de ciency of clotting factor
XI.It is a much rarer form and constitutes less than 2 %
of all cases of hemophilia.
Patients with hemophilia are prone to slow, steady, and
continuous bleeding a er minor trauma. Bleeding can also
occur spontaneously without trauma. e most important
complications include bleeding into joints ( hemarthrosis ),
internal bleeding, intracranial bleeding, and susceptibility
from hematological infections due to recurrent blood transfusions.
Bleeding into the joints can occur in any joint, but it commonly a ects the knees and the elbows. Target joint is a term
used in hemophiliacs to indicate a joint with more frequent
bleeding than other joints, commonly the knee. e joint
synovium is rich in blood vessels, causing it to bleed easily.
Multiple bleeding within the joint causes synovium hypertrophy, which later causes articular joint destruction and
osteoarthritis. Patients with joint bleeding experience severe
pain, due to swelling of the a ected joint with stretching of
the intra-articular structures by the entrapped blood.
Recurrent joint bleeding can stimulate the growth plate,
resulting in bony hypertrophy.
Bleeding into the muscles (e.g., the psoas muscle), if not
controlled, may lead to muscular swelling, nerve damage, and
development of compartment syndrome. Hemophilic pseudo-
tumor is a rare complication of hemophilia, occurring in
1–2 % of hemophiliacs. It results from a chronic, encapsulated, slow-growing intramuscular hematoma that displaces
the surrounding tissues. Limb enlargement, bone resorption,
and muscle and skin necrosis all can be seen in severe cases.
Internal bleeding can be seen as skin bruising, nose bleeding, or blood in the urine (hematuria). Moderate hemophiliacs
may bleed 5–6 times per year. Severe hemophiliacs may have
2–3 bleeding episodes per month.
Intracranial bleeding may occur within the brain parenchyma or within the subarachnoid space. Altered consciousness, headache, nausea, and vomiting in a patient with
hemophilia a er a minor head injury should be considered
intracranial bleeding and investigated with a head CT without delay.
Myositis ossi cans ( MO ), also known as “Sterner’s tumor,”
is a rare, nonneoplastic condition characterized by formation
of bone within muscles. e disease may be hereditary ( brodysplasia ossi cans progressiva, Munchmeyer disease), nontraumatic (e.g., in hemophilia), or traumatic, which is the
most common form (e.g., a er muscle trauma). e previous
classi cation is applied to intramuscular MO; however, MO
can arise against a bone (parosteal MO) or evolve as periostitis (periosteoma).
In the early stages of MO, there are richly vascularized
broblastic cell proliferations with prominent mitotic activity that mimic malignancy (early pseudosarcomatous phase).
As the cells mature, the lesion typically shows three distinct
zones. e rst zone is composed of rapidly proliferating
broblasts with areas of hemorrhage and necrosis; the intermediate layer is composed of osteoblasts with osteoid matrix
with islands of endochondral ossi cation; the third outer
zone is composed of mature bone, separated from the surrounded tissue by myxoid- brous tissue. e peripheral zone
usually calci es at 6–8 weeks a er lesion initiation, and complete lesion ossi cation can be seen 5–6 months from the
onset of symptoms. Up to 30 % of lesions regress and resolve
spontaneously with maturation.
Patients with MO typically present with painful swelling,
commonly in the lower limbs (60–75 % of cases). Patients,
especially children, may not recall the incidence of trauma.
Diagnostic imaging approach for a patient with painful swelling, with suspicion of MO, should start with conventional
radiography, US, CT, and later MRI, as the MRI appearance of
MO is generally nonspeci c unless the lesion starts to mature.
History of trauma is important to suspect MO; however, the
absence of history of trauma does not exclude it.
D i erential Diagnoses andRelated Diseases
Von Willebrand ’ s disease is a bleeding disorder that mimics
hemophilia and results from de ciency of von Willebrand
factor.
Signs on Radiographs
5 Enlargement of the epiphysis (100 %), joint
swelling with soft-tissue swelling (81 %), and
osteoporosis (95) are commonly found in
hemophilic arthropathy. Reduction of the joint
space and signs of osteoarthritis are also
commonly found (. Fig. 9.5.18 ).
Соседние файлы в папке Библиотека им академика М.И. Перельмана