Lymphadenopathy and Splenomegaly Flashcards
Where is the hydrostatic pressure greater? At the arterial end or the venous end?
-
Arterial end
- Hydrostatic pressure > Oncotic pressure
-
Venous end
- Osmotic pressure > Hydrostatic pressure
Describe the lymphatic system.
- Interstitial fluid is absorbed by lymph capillaries.
- Lymph capillaries are thin-walled, endothelial tubes.
- Avascular structures (epidermis, cornea, cartilage) do not have lymph vessels either.
- Capillaries join and form lymph vessels.
- Lymph in the vessels is filtered by lymph nodes.
Describe the structure of lymph vessels.
- The lymph vessels, similar to veins, have valves inside of them.
- Valves prevent retrograde flow of lymph.
- A route for spread of disease:
- Seed in the nodes
- Distant metastasis - not a good sign for prognosis
- ALWAYS examine the regional lymph nodes.
What is the sentinel lymph node?
- The sentinel lymph node is the hypothetical first lymph node or group of nodes draining a cancer.
Describe the anatomy of the spleen.
- Lymphoid organ below the left diaphragm,
- Red pulp - sinuses lined by macrophages.
- Receives red cells.
- White pulp - similar to lymph node.
- Receives plasma and white cells.
Describe the function of the spleen.
- Red cell phagocytosis - e.g. old, damaged, antibody-coated cells removed.
- Site of haematopoiesis in foetus and if ‘additional’ space is needed in adults.
- Blood pooling - platelets > red cells.
What size are normal nodes?
What size are para-aortic or mediastinal nodes before they cause symptoms?
- Normal nodes are up to 10mm (15mm in the groin) in short axis (imagine a kidney bean).
- Normal nodes are easliy palpable in slim individuals (the worried well).
- Internal nodes e.g. mediastinum or para-aortic are often 5-10cm before causing symptoms.
What are the red flags associated with lymphadenopathy?
- Persistent lymph node or nodes for >6 weeks.
- Firm, hard lymph node.
- Lymph node >2cm in size.
- Rapidly increasing in size.
- Significant unintentional weight loss, night sweats, appetite loss.
- Exposre to HIV or hepatitis.
- Unexplained fever in a returning traveller.
- Breast lumps or symptoms suggestive of common cancers.
Describe the surgical sieve.
- Possible causes - MEDIC HAT PIN.
- Metabolic - conditions relating to metbolism, biochemistry etc.
- Endocrinological - conditions relating to various secretory systems.
- Degenerative - conditions relating to age-related or stress-related destruction of tissue.
- Inflammatory / infective - conditions that primarily present in a way that involves the profane activation of the immune system.
- Congenital - conditions present from birth.
- Haematological - conditions relating to the blood system.
- Autoimmune - conditions relating to the inappropriate activation of the immune system.
- Traumatic - conditions relating to a physical impact between two or more objects or environmental exposure.
- Psychological - conditions related to a chemical imbalance or a disorder of thought process.
- Idiopathic or iatrogenic - conditions without a known cause / caused by a doctor or resulting from treatment.
- Neoplastic - conditions relating to cancers.
Describe the features of infective lymphadenopathy.
- Regional response to infection - look for ‘red streak’.
- Systemic infections, e.g. EBV / CMV / toxoplasma / HIV.
- Nodes often tender / short history / variable size.
- History / examination / passage of time / ?viral serology or PCR should help.
What diseases can cause inflammatory lymphadenopathy?
- Local or systemic response to inflammation, e.g. eczema.
- Auto-immune conditions e.g. rheumatoid arthritis or lupus.
- Sarcoidosis (skin / lungs / lymph nodes).
- Castleman’s disease (Human herpes virus-8 (HHV*) associated).
Describe the features of neoplastic lymphadenopathy.
- Secondary
- Existing malignancy or new diagnosis (latter e.g. melanoma / ENT / lungs).
- Consider nodal drainage patterns.
- Often hard, fixed nodes.
- Fine needle aspiration (FNA) often useful.
- Treatment plan depends on type and extent of tumour.
- Primary lymphoproliferative disease
- Often rubbery, mobile, non-tender nodes - local / systemic.
- Check for ‘B symptoms’ - fever to 38°, drenching sweats, weigh loss >10% in <6 months.
- FBC - ?chronic lymphocytic leukaemia.
- Lactate dehydrogenase - non-specific marker of cell turnover.
- FNA unhelpful, ?core or excision biopsy.
Give an overview of the staging of lymph node involvement in malignancy.
What factors are included in the prognostic index for Hodgkin’s disease?
- Age
- Stage
- Hb
- Albumin
- Male
- Lymphopenia
- Low WBC
What factors are included in the prognostic index for Diffuse large B cell lymphoma (DLBCL)?
- Age
- Stage
- LDH
- Performance status
- Number of extra-nodal sites
What factors are included in the prognostic index for follicular lymphoma (FL)?
- Age
- > 4 different sites
- LDH
- Hb
- Stage 3 or 4
What factors are included in the prognostic index for chronic lymphocytic leukaemia (CLL)?
- Age
- Stage (includes Hb / platelets)
- β2 microglobulin
- p53 mutation status
What are the treatments for the diffrent types of neoplastic lymphadenopathy:
- Hodgkin’s disease
- Diffuse large B cell lymphoma
- Follicular lymphoma
- Chronic lymphocytic leukaemia
- Treatment often adjusted by risk index and initial response e.g.:
- Hodgkin’s disease and DLBCL - Short duration chemo- then radio- therapy for localised disease, extended or more intensive chemo for extensive disease.
- Follicular lymphoma - radiotherapy for localised, ?watch and wait for asymptomatic disease.
- CLL - watch and wait / chemo- and immunotherapy / targeted agents e.g. ibrutinib.
What investigations are used to stage lymphoma?
- Physical examination
- CXR
- CT
- MRI if bone of CNS concerns
- PET-CT (positron emission tomography) e.g. in Hodgkin’s disease or early stage DLBCL
How do you quantify splenomegaly?
- Spleen size relates to age and height.
- 90% confidence interval of maximum spleen length by abdominal USS by height of the person.
Describe the clinical examination of a patient with ?splenomegaly.
- Normal size spleen can rarely be palpated.
- Often needs to be 16-18cm pole to pole to be palpable.
- Enlarges towards the right iliac fossa. Anterior structure so displaces bowel thus dull to percussion.
What are the causes of splenomegaly?
- Related to:
- Function as a lymphoid organ
- Function as reticulo-endothelial organ
- Function as haematopoietic site
- Related to anatomy of portal circulation
What are the reasons for splenomegaly with respect to its lymphoid function?
- Similar range as for lymph nodes.
- Add malaria, schistosomiasis and other tropical causes.
- Also Felty’s syndrome - splenomegaly with e.g. lupus or rheumatoid arthritis.
What are the reasons for splenomegaly with respect to its function as a reticuloendothelial organ?
- Site of RBC estruction so, any cause of haemolysis.
- Storage disorders e.g. Gaucher disease.
- Amyloid
What are the reasons for splenomegaly with respect to its function as a haematopoietic site?
- 20% of newborns have a palpable spleen before medulla of bone takes over.
- Chronic myeloid leukaemia.
- Myeloproliferative disorders e.g. primary polycythaemia, myelofibrosis.
What are the reasons for splenomegaly with respect to its relation to the portal circulation?
- Portal circulation - haemodynamic pressure.
- Cirrhosis (hepatic)
- Portan vein thrombosis (pre-hepatic)
- Severe right heart failure (post-hepatic)
How would you investigate splenomegaly?
- History
- Examination
- Simple bloods
- FBC
- Reticulocytes
- Blood film
- Liver function
- LDH
- Imaging
- ?? Bone marrow
- ?? Splenic biopsy
Describe the imaging of the spleen in splenomegaly.
- USS
- CT
- Define:
- size
- focal changes
- splenic vessels
- associated pathology in nodes / liver etc.
