Lymphatics

Question 1

what are some common infective causes of lymphadenopathy?

Answer 1

• EBV
• HIV
• adenovirus
• eczema
• CMV
• rubella
• TB
• roseala infantum
• bacterial lymphadenitis

Question 2

what are some neoplastic differentials for lymphadenopathy?

Answer 2

• Non-Hodgkin’s lymphoma - painless in neck, axillary, groin, *throughout
• Hodgkin’s lymphoma - painless in neck, axillary, groin
• Metastatic solid tumour
• Leukaemia eg: CLL

Question 3

what are some other causes of lymphadenopathy?

Answer 3

• Autoimmune - SLE, RA
• Graft vs host disease
• Drug induced - Methotrexate, Ciclosporin, Phenytoin, Isoniazid
• Sarcoidosis

Question 4

what is the anatomy of the spleen?

Answer 4

• white pulp is the accumulation of lymphocytes around an arterial vessel which enters the red pulp as a capillary
• red pulp consists of splenic venous sinuses and cords with macrophages found lining the sinuses
• the capillaries from white pulp, empty blood into the cords where macrophages phagocyte the old RBC

Question 5

what are some functions of the spleen?

Answer 5

• provides environment in which lymphocytes proliferate and erythrocytes are recycled
• phagocytosing opsonized bacteria
• reservoir of blood which can be pumped back when needed
• 1/3 of total platelets stored in spleen
  
  • in splenomegaly upto 90% platelets sequestrated in spleen resulting in thrombocytopenia
• foetus spleens are a site of haematopoiesis

Question 6

what are some important causes of hyposplenism?

Answer 6

• splenectomy
• sickle cell
• coeliac and dermatitis herpetiformis
• graves
• SLE
• amyloid

Question 7

what are some features seen on blood film in hyposplenism?

Answer 7

• Howell-Jolly bodies - nuclear remnants
• Siderocytes - non-haemoglobin iron

Question 8

how is hyposplenism managed?

Answer 8

• vaccinations - pneumococcal, influenza, nisseria meningitides, meningococcal
• prophylactic antibiotics
• rescue antibiotics - for suspected infections
• specific advice for travelling abroad and vaccinations

Question 9

What can cause a massive spleen?

Answer 9

• myelofibrosis
• chronic myeloid leukaemia
• visceral leishmaniasis (kala-azar)
• malaria
• Gaucher’s syndrome

Question 10

what are some other causes of splenomegaly?

Answer 10

• portal hypertension e.g. secondary to cirrhosis
• lymphoproliferative disease e.g. CLL, Hodgkin’s
• haemolytic anaemia
• infection: hepatitis, glandular fever
• infective endocarditis
• sickle-cell*, thalassaemia
• rheumatoid arthritis (Felty’s syndrome)