What is Lymph System? – Written by Dr harold Gunatillake-FRCS, MBBS, FICS, FIACS, AM(Sing)-Health writer
Just like there are arteries and veins to circulate blood carrying nutrients, other metabolites and waste material to and from the tissues and organs there is another system called the lymph system which is filled with watery milkish fluid called lymph carrying nutrients and waste material between the body tissues and the bloodstream? You could compare the two transport systems like the road and railway systems, respectively. The lymph system is composed of very tiny thread-like meshwork of vessels under the skin (subcutaneously) and deep in relation to the blood vessels, mainly accompanying the veins.
Like the railway system there are stations joining this system called nodes, commonly found in the neck, armpit and the groin. These nodes are bean shaped organs and are part of your body’s defensive barrier – the immune system. There are several hundreds of these glands in the body. The lymph carries bacteria and cancer cells into these nodes where white blood cells attack and kill them. These glands enlarge in the process and become palpable. Even after the infection is controlled and or cancer cells killed and prevented from further travel, they can remain enlarged for many years. We call them shotty glands which you can feel by rolling your fingers over the gland.
In the upper neck behind the angle of the jaw there are a few glands labelled as tonsillar glands. These regional glands enlarge when there is an infection of the tonsils. The tonsils could enlarge and become cherry-like and may need removal for the tonsillar gland to subside.
When you have a foot infection like in-between toes, or nail-bed, the groin glands get activated and large and tender- goes into defensive mode to kill any germs that ascend through the lymph vessels in the lower extremities.
There are lymph systems in your spleen, tonsils, adenoids (back of the nasal cavity), and thymus (gland behind the upper sternum (breast bone). These organs fight bacteria and viruses that cause infection or any illness. The thymus gland makes defensive white blood cells to kill germs when you are young and shrinks off as you age and is replaced by fat tissue.
The spleen though defensive organs like the appendix can burst and may require removal. Spleen enlarges as a defensive organ in Malaria and certain kinds of leukaemia. You tend to get infections without you spleen and yearly vaccinations are given to prevent certain bacterial infections.
When your doctor feels the sides of your neck, he or she is checking your lymph glands to see if they are swollen and tender to the touch. Swollen glands are triggered by bacteria and viruses like the common cold virus, and they resolve when the infection clears.
Lymphoma
The white blood cells have a life span- they die and new cells grow. In the tumour lymphoma quite prevalent these days the white blood cells in the glands do not die, but grow and further multiply. With time they lose their defensive function. It is a type of blood cancer that occurs in the white cells and the glands may develop in many parts of the body, including lymph nodes, spleen, bone marrow and other organs. You may have heard Hodgkin’s disease which is one type of lymphoma.
Lymphedema
In Sri Lanka this was prevalent in the past when filarial mosquito was not eradicated. The legs swell, and sometimes the scrotum, too due to blockage of the lymphatic threads in the lower limb, and lymph fluid retention and tissue swelling occurs to cause the oedema. Part of the swelling is due to the reactionary fibrous tissue.
Lymphedema occurs in the upper extremities after radical breast surgery for cancer. When arm-pit lymph glands are damaged or removed in the radical procedure there is blockage of the flow of lymph mainly from the arm. There is no cure to remedy the swelling.
Lymphadenopathy
This is a term doctor’s use when the lymph nodes are abnormal in size, number or consistency and is often used as a synonym for swollen or enlarged glands. Common causes of lymphadenopathy are infection, autoimmune disease or malignancy.
Most times doctors need to do further investigations to find out the cause of the lymphadenopathy.
Acute lymphangitis
When lymphatic vessels get inflamed due to a virus or bacterial invasion through a skin cut or wound you could see red streaks going from the wound towards the nearest lymph glands, very prominent on white skins. This could be accompanied with fever, chills and general sense of illness. You need to see your doctor to check out the cause and treatment.
Lymphatic stasis
This is a situation where the lymphatic flow is reduced due to immobility being seated for long hours on a plane trip. Frequent movements of the ankles in a rotatory manner, sometimes demonstrated on the screen, helps to pump the lymphatic fluid, or regular walks on the isle would do.
Infective mononucleosis
This is caused by Epstein-Barr virus spread through usually the saliva. This affects mostly children, and may not produce any symptoms. In young adults the disease results in fever, sore throat, and enlarged lymph flands in the neck. Most people get better in tow to four weeks, however the tiredness may last for months. In a small percentage of cases the spleen can enlarge and rupture in this disease and needs emergency removal.
The bottom line is if you feel any enlarged glands in your neck arm-pit or groins or red streaks or patches on your limbs see your doctor for a check-up.
