MRCP revision battle 39.1: Hodgkin's Lymphoma

Its the second day of haematology fun!  Lets dive straight in...


MRCP revision battle 39.1: Hodgkin's Lymphoma
MRCP revision battle 39.2: Non-Hodgkin's lymphoma
MRCP revision battle 39.3: Systemic mastocytosis
MRCP revision battle 39.4: Thrombocytosis
MRCP revision battle 39.5: Haemophilia
MRCP revision battle 39.6: The spleen
MRCP revision battle 39.7: Autoimmune haemolytic anaemia





MRCP revision battle 39.1: Hodgkin's Lymphoma


Lymphomas are malignant proliferations of lymphocytes.  These may accumulate in lymph nodes, in organs or in the peripheral blood.


Lymphomas are divided into 2 main types: Hodgkin's, which has characteristic Reed-Sternberg cells, and non-Hodgkin's, which do not have Reed-Sternberg cells.

The slide below (by Dr Ed Uthman) shows a Reed-Sternberg cell in the centre with its characteristic mirror-image nuclei:

Staging of Hodgkin's lymphoma is done by the Ann Arbor system:

• I = one lymph node group
• II = 2 areas on one side of the diaphragm
• III = both sides of the diaphragm
• IV = extra-nodal tissues (NB the spleen is counted as an 'honorary' node)

Each stage is subdivided into A or B:

• A = no B symptoms
• B =  T>38c, night sweats or weight loss >10% in 6 months

Pel Ebstein fever = cyclical fever with long periods of normal temperature - is so rare some believe it to be mythical...


Pruritus or alcohol-induced pain are not B symptoms bit are useful indicators of relapse.


Poor prognostic factors are:

• B symptoms
• stage IV
• Hb <10.5
• lymphocyte count <8%
• male

 Histological subtypes of Hodgkin's lymphoma are:

• nodular sclerosing = most common, good prognosis
• mixed cellularity - good prognosis
• lymphocytic predominant = best prognosis
• lymphocytic depleated = least common, worst prognosis

Bloods will show:

• neutrophilia
• anaemia
• thrombocytosis
• raised ESR
• raised LDH - a useful guide to the bulk of the disease

Treatment is with radiotherapy, chemotherapy (ABVD) or both.


Now on to non-Hodgkin's lymphoma...

MRCP revision battle 39.2: Non-Hodgkin's lymphoma

Non-Hodgkin's lymphoma are a hugely diverse group of diseases and this battle is a highly edited set of highlights for MRCP revision.


Low grade 

• relatively mature cells
• indolent but usually incurable
• try local radiotherapy

High grade

• immature cells
• rapidly progressive disease but 40% curable
• treated with CHOP chemo
• includes Burkitts lymphoma

B cell lymphoma

• treated with rituximab

Lymphoblastic

• treated as ALL

Now for a short battle with an esoteric condition...

MRCP revision battle 39.3: Systemic mastocytosis

Systemic mastocytosis is a neoplastic proliferation of mast cells.


Features include:

• flushing
• abdominal pain
• monocytosis on blood film
• urticaria pigmentosa (Darier's sign)

It is diagnosed by raised serum tryptase and urinary histamine


It is vanishingly rare in real life.


So from something very rare to very common: thrombocytosis

MRCP revision battle 39.4: Thrombocytosis

Thrombocytosis = raised number of platelets.




Primary = essential thrombocythaemia

• caused by a clonal proliferation of megakaryocytes
• platelets typically >1000 (x10 to the power 9)
• abnormal function, risking either thrombosis or bleeding
• treatment = aspirin.  Hydroxycarbamide is given to lower platelets if pt is >60yrs or they have had a previous thrombosis

Secondary thrombocytosis

• reactive to
• bleeding
• infection
• trauma
• thrombosis
• infarction
• iron deficiency

Now for some haemophilia....

MRCP revision battle 39.5: Haemophilia

Haemophilia A and Haemophilia B clinically present very similarly, with bleeds into joints and muscles.

Both are inherited in an X-linked recessive way but 1/3 of cases will have no family history.

Both cause raised aPTT.


Haemophilia A = lack of factor VIII
Haemophilia B = lack of factor IX = Christmas disease


Treatment is with desmopressin and tranexamic acid.  Major bleeds may need recombinant factor VIII.  Avoid NSAIDs and IM injections.



On to an organ that has always bewildered me... the spleen

MRCP revision battle 39.6: The spleen

My dubious relationship with the spleen goes waaayyy back to medical school anatomy days when I learnt that any mass of tissue that I had absolutely no idea what it was when placed on a tray in front of me was usually a spleen.


The spleen was equally mysterious to the medical profession in general for many years, as no-one was quite sure as to its function.  It is now known to act as a reservoir for lymphocytes and so is vital in dealing with bacteraemias.


This battle will look at the 2 extremes of spleen: splenomegaly, and hyposplenism/post splenectomy.



Splenomegaly

Massive splenomegaly can occur in:

• CML
• myelofibrosis
• malaria
• leishmaniasis
• Gaucher's syndrome (= an inherited lysosomal storage disease)

Moderate splenomegaly can occur in:

• infections: typhoid, brucella, TB, glandular fever, EBV, schistosomiasis
• haematological disorders: lymphoma, leukaemia, haemolytic anaemia
• connective tissue disease: SLE, RA
• portal hypertension: cirrhosis, CCF

Splenectomy

Splenectomy is performed for a variety of reasons including:

• trauna
• ITP
• warm AIHA

2 weeks prior to splenectomy pneumoccal vaccine and HiB should be given; if the splenectomy is an emergency these should be given ASAP afterwards.
Lifelong penicillin (or erythromycin if penicillin allergic) is then also needed.


Most common serious infections after splenectomy are from encapsulated organisms such as s.pneumoniae, h.influenzae and n.meningitidis.


Blood film after splenectomy shows:

• Howell-Jolly bodies (=nuclear remnants in RBCs)
• target cells
• Pappenheimer bodies (=abnormal iron inside RBCs)

There is low IgM.


As well as hyposplenism being a problem post splenectomy, it can also occur in sickle cell disease, coeliac disease and myeloproliferative diseases



Now onwards to some AIHA...

MRCP revision battle 39.7: Autoimmune haemolytic anaemia

Autoimmune haemolytic anaemia (AIHA) is mediated by autoantibodies and results in mainly extravascular haemolysis.

AIHA will result in a positive direct antiglobulin test (= positive Coombs test)


AIHA is divided depending on the optimal binding temperatures of the autoantibodies to the RBCs.



Warm AIHA = 37C

• Ig G
• SLE, lymphoma, CLL, methyl dopa
• treatment: steroids, immunosupression, splenectomy

Cold AIHA = 4C 

• IgM
• lymphoma, mycoplasma, EBV
• treatment: keep warm, ?chlorambucil