Lymphadenopathy Flashcards
Define: lymphadenomegaly
lymph node enlargement
Define: lymphadenopathy
any abnormality of lymph node(s)
- size, shape, structure, cellular composition, necrosis
Define: lymphadenitis
inflammation of lymph nodes
What factors indicate an enlarged and/or pathological lymph node?
see it easily palpate it measurable size is increased, short axis more important - short axis >10mm - long axis >15mm - cross-section area >2.25cm^2
How should you measure a lymph node?
measure with a rule or use US
express results in mm or cm
long axis/short axis ratio is important
- reactive node: usually about 2:1 or higher
- closer to 1:1 (round node) - more likely malignant (sobiaiti index)
(submandibular, parotid and mesenteric lymph nodes may be normally round)
What are the different types of lymphadenomegaly?
localised: one LN / one LN region
regional: 2 or more contiguous regions
Generalised: 2 or more non-contiguous regions
- about 25% lymphadenopathies
What causes lymph node enlargement?
1) in situ proliferation of leukocytes (mostly lymphocytes, but also histiocytes and rarely, dendritic cells)
2) influx of lymphocytes from blood and lymph
3) infiltration by neoplastic cells
4) accumulation of abnormal substances of foreign or endogenous origin, usually phagocytosed by histiocytes
rarely:
- swelling due to necrosis or dilatation of sinuses
- suppuration
Can new LNs arise?
it has been suggested that they can originate “de novo” from clusters of lymphocytes in many sites
What should you do after noting an enlarged lymph node?
enlargement of unknown origin should NOT be treated it MUST be diagnosed
- the exception to this is if it is life threatening obstruction of upper airways by pharyngeal nodes
Should a biopsy of an enlarged LN be performed?
simple algorithmic approach is NOT possible
need to weight up pros and cons
- LN excision biopsy provides plenty info and often definite diagnosis - surgical procedure is costly and although simple it has risks (scar, nerve damage, infection, haemotoma)
What are the chances of an enlarged LN being malignant?
annual incidence of lympahdenopathy in gen pop - 0.6%
What to ask in the history?
history:
- Fam = previous cancers, immunodeficiencies, other cancer RF, TB
- Occupational = contact with animals and animal products, healthcare workers
- Ethnic origin and travel - TB, HTLV1, kikuchi lymphdenitis
- Lifestyle risks= smoking
- Co-morbidities = immunosuppression, current cancer, other autoimmunedisease, RA)
- drugs = anticonvulsants (phenytoin, captopril, mephenytoin)
What can all immunosuppresive agents cause?
e.g. methotrexate administered for RA
may cause lymphoma like growths and true lymphomas
What are the definitions of localised/region LNs and generalised?
localised- focus on drainage area
generalised = serological / haematological tests may give more useful info
- much higher risk of malignancy
What are some non-malignant conditions in which there is generalised LN enlargement?
HIV/AIDs Infectious mononucleosis SLE TB Sarcoidosis
What are the associated symptoms that increase risk of malignancy?
B symptoms
- fever >38
- drenching night sweats
- unexplained weight loss of more than 10% body weight
unexplained generalised pruritus
immunosuppression
unexplained skin rash, particularly when accompanied by oedema, fluid accumulation in body cavities or arthralgias
What is LN pain following alcohol consumption characteristic of?
hodgkin’s lymphoma - rare
What are some worrisome features of enlarged LNs?
likely malignant if:
- lower neck nodes
- abdominal nodes
- fixed to surrounding tissue
- forming aggregates
- painless
- rock hard
- very large 3-4cm
- on imaging:-round, fatty hilum not discernible. necrosis
What is a poor predictor of malignancy and what is a good one?
poor- time
- some say <4 weeks and greater than 1 yr likely to be benign however indolent lymphomas are frequently >1 yr
Age
<30 mostly benign
>50 much more likely to be malignant
What is non-TB mycobacterial infection in children?
1 in 100,000 children per year 80% <5 yrs previously healthy no immunodeficiency isolated unilateral cervical lymphadenitis painless asymptomatic no dissemination IGRA test usually negative
No consensus on treatment (excision, drugs, watch and wait)
RF largely unknown
no human to human transmission
What is the lymph node that drains the thorax, GIT and GU tract and what happens if its enlarged?
supraclavicular
- normally not palpable
over 50% are malignant
- hodgkin’s lymphoma, NHL, bronchial cancer, breast cancer
What is virchow’s node?
left supraclavicular - more frequently malignant than the right, frequently signifies an inoperable malignancy of the git
What is likely if the infraclavicular node is enlarged?
very rare, highly suspicious of hodgkin’s lymphoma
What are some potential diagnoses if the mediastinal LN is enlarged and what can it lead to?
sarcoidosis (rarely massive)
lymphoma (usually massive)]
TB
Can result in superior vena cava syndrome
