Anatomical Pathology - Leukaemia, Spleen And Lymph Nodes Flashcards
Defn hypersplenism
Peripheral blood pancytopaenia and splenomegaly (primary or secondary)
Congenital abnormalities of spleen
Accessory spleens/ splenunculi
Asplenia
Polysplenia
Causes of splenomegaly
Congestion Infection Immune disorders RBC abnormalities 1ry or metastatic neoplasms Storage disorders Amyloidosis
Causes of congestive splenomegaly
Pre-hepatic = extrahepatic portal/splenic vein thrombosis Hepatic = cirrhosis Post-hepatic = raised IVC pressure (RHF, pulmonary/tricuspid disease)
Where does pathology mainly occur in congestive splenomegaly
Red pulp
Cut surface of congestive spleen
Beefy red with little white pulp
Some firm brown nodules (areas of healed infarction - gamma gandy bodies)
Types of infection causing splenomegaly
Systemic infection Bacterial Viral Chronic malarial Granulomatous inflammation
What are gamma gandy bodies composed of?
Fibrinous and elastic tissue
Abundant haemosiderin
Dystrophic calcification
What organisms cause granulomatous inflammation of spleen
Bacterial: Tuberculosis
Fungi: histoplasmosis, cryptococcus
Protozoan: toxoplasmosis
Extreme bacterial splenomegaly
Acute septic splenitis
What causes splenomegaly in bacterial infection
Accumulation of neutrophils in sinuses and medullary cords
Why bacterial splenomegaly soft?
Proteolytic enzyme action
Immune causes of splenomegaly
Felty’s syndrome - RA and splenomegaly
SLE
RBC abnormalities causing splenomegaly
Sickle cell anemia
Hereditary spherocytosis
Neoplasms that cause splenomegaly
Hemangioma
Acute/chronic leukaemia
Myeloproliferative disorders
Hodgkin’s/ Non-Hodgkin’s lymphoma
Storage disorders that cause splenomegaly
Niemann Pick disease
Gaucher’s disease
Mucopolysaccaridoses
What is seen macroscopically in storage disorders
Red pulp expansion by macrophages (filled with abnormal storage product)
Causes of splenic rupture
Usually blunt abdo trauma (emergency splenectomy)
Spontaneous rupture - infectious mononucleosis
Causes of splenic infarction
Splenic artery occlusion due to:
Emboli
Local thrombosis (sickle cell, myeloproliferative disorders, malignant infiltrates)
Causes of splenic atrophy
Sickle cell (infarcts) Malabsorption disease (eg coeliac disease)
Slate grey spleen?
Malarial infection
Causes of infective granulomatous lymphadenitis
TB
Toxoplasma
Infective causes of necrotising lymphadenitis
Lymphogranuloma venereum
Cat scratch disease
Histological feature of necrotising lymphadenitis (infective)
Stellate abscesses in lymph node surrounded by palisades histiocytes
Cause of infective follicular hyperplasia
Syphilis
Causes of infective para cortical hyperplasia
Infectious mononucleosis (EBV)
Causes of non infective granulomatous lymphadenitis
Sarcoidosis
Crohn’s
Reaction to tumor Ag
Foreign body
Causes of non infectious necrotising lymphadenitis
Kikuchi’s disease
SLE
Non infectious causes of follicular hyperplasia
RA
Non infectious causes of para cortical hyperplasia
Dermatopathic lymphadenopathy
Eg. Eczema, psoriasis
Cutaneous T cell lymphoma
No infectious causes of sinus histiocytosis
SHML/ Rosia-Dorfman syndrome
Langerhan’s cell histiocytosis
Defn persistent generalized lymphadenopathy syndrome
Persistent extrainguinal LN in two or more contiguous sites.
Greater than three months.
Unknown aetiology besides HIV.
Distinguishing features of Hodgkin’s Disease
Rarely involves tonsillar area, skin, stomach, ileum.
Reed-Steenberg cells
Reed-Steenberg cell morphology
Large, bi-/multi-lobulated nuclei
Large eosinophilic nucleoli
Slightly acidophilic cytoplasm
WHO classification of non Hodgkin’s based on..
Type/ number of neoplastic cells
Pattern of fibrosis
Proportion of reactive lymphs to neoplastic cells
Two main types of Hodgkin’s Disease
Nodular lymphocyte predominant HD
Classic HD
Four main type of classic HD
Lymphocyte rich HD
Nodular sclerosing HD
Mixed cellularity HD
Lymphocyte depleted HD
Spread of HD (?pattern)
Generally via lymphatics. Mostly, contiguous groups of LN are involved
Clinical outcome of HD influenced by
Stage
‘‘B’’ constitutional symptoms
Disease bulk
Extent of splenic involvement
Complications of HD
Infection (NB) [T cell immunity defect, splenectomy, opportunistic infections]
Cachexia
Massive organ infiltration
Complications of Rx [corticosteroids=immunosuppression, endocrine dysfunction (hypothyroid,hypogonadism), pulmonary inflammation and fibrosis, pericardial fibrosis]
Secondary malignancies
Risk factors for NHL
Viruses - EBV, HTLV1
Immunodeficiency - 1ry or 2ndry
'’B’’ symptoms of lymphoma
Fever
Weight loss
Night sweats
System used to stage lymphoma
Ann-Arbor system
Stage 1 lymphoma
Single LN region or structure
Stage 2 lymphoma
2 or more LN region on same side of diaphragm
Stage 3 lymphoma
LN regions on both sides of diaphragm
Stage 4 lymphoma
LN region with non-contiguous extra nodal involvement
Complications of NHL
Immunodeficiency (disease/ Rx)
Infection
Neutropenia, thrombocytopenia, anemia (replacement of normal bone elements by NHL, marrow damage during Rx, involvement of spleen by NHL = hypersplenism)
Common site of extra nodal NHL
GIT
Thyroid, salivary glands
*no site exempt
Extra nodal NHL may arise following
H. Pylori gastritis Autoimmune thyroiditis (Hashimoto's) Autoimmune inflamm of salivary/lacrimal glands (Sjogren's)
Known as MALT lymphomas
Presentation of NHL
Involves any LN group in body, haphazard distribution. May involve lymphoreticular tissue (spleen, BM, liver, tonsils) or extra nodal tissue. May even involve nonlymphoid tissue such as skin, brain, thyroid.
Usually painless rubbery enlarge LNs. Symptoms may occur as a result of tissue infiltration.
Fish-flesh. Loss of nodal architecture.
Common forms of mature B cell NHL
Follicular
Diffuse small lymphocytic
Diffuse large cell
Burkitt’s lymphoma
Histology of Burkitt’s lymphoma
Starry-sky = sheets of primitive medium sized blastic lymphoid cells and many histiocytes
Types of Burkitt’s lymphoma
Endemic
Non-endemic
AIDS associated
Types of mature T cell NHL
Anaplastic large cell lymphoma
Mycosis fungoides and sezary syndrome (cutaneous)
Endemic Burkitt’s presents with
Enlarged jaw or ovaries.
Nodal involvement not characteristic.
Children 4-8yrs.
Presentation of non-endemic Burkitt’s
Intestinal involvement common (ileum) with mesenteric LNs.
Older children.
Causes of massive splenomegaly
Chronic malaria Gaucher's disease CML Myelofibrosis Kala-azar Infectious mononucleosis
Three complications of splenomegaly
Anaemia
Thrombocytopenia
Neutropenia
Microscopic features of granulomatous lymphadenitis
Cluster of epitheliod histiocytes w/wout necrosis.
Giant cells
