Anatomy, Physiology & Pathology – Assignment 8.1
Pathologies of the Lymphatic System
Hodgkin Disease & non-Hodgkin Lymphoma
Hodgkin lymphoma and non-Hodgkin lymphoma are two forms of cancer. Each year on average 1,850 people are diagnosed with Hodgkin lymphoma, more common in young adults and adults over 70 whilst on average 11,500 people are diagnosed with non-Hodgkin’s lymphoma this condition usually occurs in children, teenagers and young adults. The difference between Hodgkin and non-Hodgkin lymphoma is the differences seen under the micro-scope that differentiates them, Hodgkin contain Reed Sternberg cells whereas non-Hodgkin don’t contain these cells, from this diagnosis they will then be treated differently.
Causes
The exact reason to the cause of Hodgkin and non-Hodgkin lymphoma is not fully understood, what medics do know is that a change in the workings of the DNA of the white blood cell known as B lymphocytes. In normal circumstances the cells receive information, when to grow and multiply, but changes to the DNA can cause these instructions to fail and the cell will uncontrollably multiply and cancer can develop. As the cells multiply and more abnormal cells are produced they group together to form a lump referred to as a tumour. What medics haven’t fully understood is what makes these changes to the DNA happen.
It usually occurs in one or more of the lymph nodes and can occur in more than one area of the body most common in the lymph nodes in the neck, from this area it can spread through the lymphatic system to lymph glands within other areas of the body, it can then spread further to the:
• Spleen
• Liver
• Lungs
• Bone marrow
• Skin (Bupa.co.uk)
In some instances Non-Hodgkin lymphoma initially develops in an organ or elsewhere within the body outside of the lymphatic system.
There are a number of various types of non-Hodgkin lymphoma and are divided up into B-cell lymphomas and T-cell lymphomas depending on which cell they develop within.
B-cell lymphomas – B-cell lymphomas are more prevalent than T-cell lymphomas. It develops when the body produces abnormal B-cell lymphocytes. The more common are:
• Diffuse large B-cell lymphomas
• Follicular lymphomas
The less common are:
• Burkitt Lymphoma
• Extranodal marinal zone B-cell – MALT
• Lymphaplasmacytic lymphoma
• Mantle cell lymphoma
• Mediastinal large B-cell lymphoma
• Nodal marginal zone B-cell lymphoma
• Small lymphocytic lymphoma
• Thyroid lymphoma
T-cell lymphomas – T-cell lymphomas aren’t prevalent. It develops when the body produces abnormal white blood cells known as T-lymphocytes. The various strains are:
• Peripheral T-cell Lymphoma
• Skin (cutaneous) lymphomas
• Anaplastic large cell lymphoma
• T-cell lymphoblastic lymphoma
There are different types of Hodgkin lymphomas, the most common known as classical types are detailed below:
• Nodular sclerosing
• Mixed cellularity
• Lymphocyte-depleted
• Lymphocyte-rich
• Nodular lymphocyte-predominant type – this is a rare strain with only 5% of all Hodgkin lymphomas being diagnosed as this type.
It is understood that lymphoma is not an inherited disease and isn’t contagious. There are certain factors that increase the chance of developing lymphoma but these factors cannot be the initial cause of the disease. The factors include:
Complications with the immune system
• Following an organ transplant and taking medication to prevent rejection.
• Having HIV, as this weakens the immune system.
• Autoimmune disorders, such as sjogren syndrome, which can over stimulate the immune system and lead to certain types of lymphoma.
Certain infections such as:
• Epstein-Barr virus – this causes glandular fever which is linked to certain types of lymphoma.
• Helicobacter pylori – a bacteria that causes inflammation and ulcers in the stomach which can cause gastric MALT lymphoma
Close relatives (siblings or parents – the risk of developing lymphoma is ever so slightly higher. As lymphomas are not common the chance is still low as there are no specific genes for lymphoma that can be inherited.
Older Generation – More prevalent in the older generation due to the bodily functions naturally slowing down and there being more changes within the body for it to deal with.
The multi-hit theory and lymphoma – all the above factors only occur in a few diagnosis of lymphoma within the UK, it is uncommon for a person to have one or more of the above risks to develop lymphoma.
It is believed that quite a few changes have occurred to the genes before lymphoma has developed, doctors refer to this has the ‘multi-hit theory’.
Signs & Symptoms
The most common symptom of Hodgkin’s lymphoma is a swelling caused by a build-up of lymphocytes (white blood cells) congregating within a lymph node/glands. The swelling usually occurs in the neck, armpit or groin.
Other symptoms include:
• Night sweats
• Unintentional weight loss
• A high temperature (fever)
• A persistent cough or feeling of breathlessness
• Persistent itching of the skin all over the body (NHS.Choices.net)
Depending on where in the body the swollen lymph glands are located will determine the other symptoms. “For example if the abdomen is affected you may have abdominal pain or indigestion”.
(NHS.Choice.net)
Occasionally, people may have abnormal cells within their bone marrow during the diagnosis process which may cause them to develop:
• Persistent tiredness and fatigue
• An increased risk of infections
• Excessive bleeding – such as nose bleeds, heavy periods and spots of blood under the skin
(NHS.Choice.net)
Some people may experience pain in their lymph glands during consumption of alcohol this is normally associated with Hodgkin lymphoma.
Cellulitis
Cellulitis is an infection of the skin that can affect the underlying layers of the skin and the tissue beneath. It can develop suddenly and is non-contagious.
Causes
Cellulitis is an infection of the skin’s layers of tissue, as a result of the skins surface being damaged and open to the outside elements, this provides a weak point in the skin’s defences for bacteria to attack the underlying tissue. The break to the skin’s surface only needs to be tiny, it may even be unseen, for bacteria to enter. There are numerous types of bacteria but the most common are staph (Staphylococcus aureus) then strep (Group A Streptococcus).
The cause of the break to the skin defences may be:
• Cut or graze
• Burn
• Animal, human or insect bite
• Puncture wound
• Venous leg ulcer
• Skin conditions such as atopic eczema or athlete’s foot (NHS.Choice.net)
It may be a result of contaminated water entering an open wound to the skin. In some cases cellulitis can develop when there has been no break in the skin’s defences.
Certain health conditions can increase a person’s risk of developing the condition:
Diabetes – If diabetes isn’t managed properly it can prevent the immune system working efficiently. Also poorly managed diabetes can affect the efficiency of the circulation system which can lead to the development of ulcers, these provide entry points for bacteria.
Weakened Immune System – HIV and Aids can weaken a person’s immune system which makes it more difficult to respond to infections.
Certain medications can also weaken the immune system such as; chemotherapy for treating cancer, immunosuppressants which prevent people who have organ transplants rejecting the organ, pro-longed use of corticosteroids tablets and creams which are anti-inflammatory medication.
Symptoms
Cellulitis causes the skin to become inflamed and a rash will develop which is; red, tender, swollen, warm and painful.
Other systems can develop before or in conjunction with the rash and include:
• Nausea
• Shivering
• Chills
• A general sense of feeling unwell
Rheumatoid Arthritis
Rheumatoid arthritis is a condition that affects joints and surrounding tissue, they can become inflamed swollen, stiff and painful.
Cause
Rheumatoid arthritis is caused by the body’s immune system attacking its joints and surrounding tissue. In normal circumstances antibodies are released to fight infection and bacteria but instead attack the surrounding tissue of the joints. This leads to the joint and surrounding tissue becoming inflamed and painful, this results in chemicals being released that thickens the joint tissue and cause damage around the joint including:
• Bones
• Cartilage
• Tendons
• Ligaments
Over time if the condition is left untreated the damage caused by the chemicals will weaken the joint until it’s completely destroyed.
It’s not fully understood what causes the immune system to attack itself but a there are a number of reasons that can increase the chance:
Inherited – there are some links that rheumatoid arthritis can be common in some families, but it is believed that it is low risk of inheriting the condition as genes are only slightly linked to the condition.
Hormones – rheumatoid arthritis is more prevalent in women than men, this may be due to the hormone, oestrogen, as women naturally have higher levels than men. Research isn’t conclusive on this.
Smoking – this can increase the risk of developing rheumatoid arthritis as some research has suggested.
Symptoms
The symptoms are different for each person they may develop quickly over days or gradually over a number of weeks, they may be intermittent and flare-ups may occur.
Normally it affects the joints in hands and feet but it can affect joints anywhere within the body. It usually affects joints that are on the same side of the body and at the same time.
Symptoms can include:
Pain – this is normally a throbbing and aching pain, more acute in the morning and after resting.
Stiffness – it can cause the joints to feel stiff which means the joint cannot be bent easily and limited movement can be experienced within the joint. Again this is more acute in the morning or after resting.
Swelling, warmth and redness – as the linings of the joint become inflamed this can cause the joint to become swollen leading to warmth building within the joint which will be tender when touched.
As well as experiencing the above with the affected joints some people may experience other symptoms:
• Tiredness and a lack of energy
• A high temperature
• Sweating
• A poor appetite
• Weight loss