The lymphatic system consists of lymph vessels, lymph nodes, and lymph that work together to transport fluid and defend the body against disease. Lymph is a fluid containing white blood cells that flows through lymph vessels and lymph nodes, where the nodes filter out pathogens and foreign materials. The lymph eventually drains into the bloodstream via two main ducts. Disorders can occur if the lymphatic system becomes blocked or infected, impairing its ability to circulate lymph and mount an immune response.

1. LYMPHATIC SYSTEM
Presented by:
Mr.Vijayreddy Vandali
M.Sc(N),PGDHA,PGCDE.
ASSOCIATE PROF CUM VICE-PRINCIPAL
SCHOOL OF NURSING, P P SAVANI UNIVERSITY,
SURAT, GUJARAT, INDIA.

2. IMPORTANT TERMS
• Lymph - a fluid that contains white blood
cells that defend against germs
• Lymph vessels - vessels that carry lymph
throughout your body. They are different
from blood vessels.
• Lymph nodes - glands found throughout the
lymph vessels. Along with your spleen, these
nodes are where white blood cells fight
infection.

3. LYMPHATIC SYSTEM
• Protects body against foreign material
• Assists in circulation of body fluids between cells
and bloodstream
• Transports dietary fats

4. LYMPHATIC SYSTEM
(cont.)• Consists of:
- Lymph
- Network of vessels
- Lymph nodes and nodules
- Tonsils
- Spleen
- Thymus gland
- Bone marrow

7. LYMPH (lymph = clear fluid)
• Derived from tissue fluid
• Contains more white blood cells than plasma
• Enters node through afferent lymphatic vessels
• Flows through node in one direction

10. LYMPH (CONT.)
• flows through sinuses in lymph node cortex and then
into the medulla
• exits the lymph node through efferent lymphatic
vessels
• must be returned to blood stream to maintain blood
volume and pressure

13. LYMPH CAPILLARIES
• Microscopic closed-ended vessels
• Located next to blood capillaries in tissue spaces
• Larger diameter than blood capillaries
• Are very permeable and collect tissue fluid and
proteins
• Lymph capillaries merge to form larger lymph
vessels

14. LYMPH VESSELS
• Resemble veins but have thinner walls and more
valves
• Ends of endothelial cells overlap
- Act as one-way valves allowing interstitial fluid to
flow in but not out
• Attached to surrounding tissue by anchoring
filaments

16. LYMPH VESSELS (cont.)
• No pump for lymph
• Lymph is kept moving by:
- Constriction of vessels
- Skeletal muscle pump
- Respiratory pump
• At intervals along vessels lymph flows into lymph nodes
• Lymphatic vessels unite to form lymph trunks

17. LYMPH TRUNKS
• formed by lymphatic vessels uniting
• large tubes
• empty their lymph into lymphatic ducts

18. LYMPHATIC DUCTS
• Lymph empties into two conducting ducts:
- the thoracic duct (left lymphatic duct)
- the right lymphatic duct
Lymph from these ducts enters the blood stream via
the left subclavian vein and the right subclavian vein

20. Thoracic Duct
(left lymphatic duct)
• about 15-18 inches (38-45 cm) in length
• begins as a dilation called the cisterna chyli
• main collecting duct of lymphatic system
• receives lymph from lower body and upper left
quadrant
• empties into the left subclavian vein

21. CISTERNA CHYLI
• large lymph vessel
• formed by the union of lymph vessels from lower
body
• located anterior to the second lumbar vertebra
• continues superiorly as thoracic duct

22. RIGHT LYMPHATIC DUCT
• about 0.5 inches (1.5 cm) in length
• receives lymph from upper right quadrant
• empties into the right subclavian vein

23. LYMPH NODES
• oval or bean-shaped
• masses of lymphatic tissue
• aid in defense and white blood cell formation
• located along length of lymphatic vessels
• scattered throughout the body usually in clusters

26. LYMPH NODES (cont.)
• covered by a capsule
• contain capsular extensions called trabeculae (form partitions
within node)
• internal to capsule are reticular fibers and fibroblasts
- form framework of a lymph node
• Two main regions of a lymph node:
- cortex
- medulla

27. CORTEX
• outer region directly beneath the capsule
• contains densely packed lymphocytes arranged in
masses called follicles
- outer rim of follicle contains T cells, macrophages,
and follicular dendritic cells (aid in T cell activation)

28. MEDULLA
• inner region
• lymphocytes are arranged in strands called medullary
cords
- contain macrophages and plasma cells

29. BIOLOGICAL FILTRATION
• as lymph passes through a node bacteria and other
foreign materials are trapped by reticular fibers within
the node
- bacteria are then phagocytized by macrophages

30. BIOLOGICAL FILTRATION
(cont.)
• plasma cells produce antibodies to antigens in the
lymph
• antibodies, lymphocytes, and monocytes are
eventually returned to the blood via subclavian veins

31. MAJOR LYMPH NODES
• cervical
• axillary
• inguinal
• mesenteric

33. CERVICAL
• located in neck area
• filter lymph from head and neck

34. AXILLARY
• located in armpits
• filter lymph from hand, arm, breast

35. INGUINAL
• located in groin area
• filter lymph from lower extremities and external
genital organs

36. MESENTERIC
• located in abdominal peritoneum
• aid in infection control after abdominal surgery
• filter lymph from abdominal cavity

37. METASTASIS
• process by which bacteria or body cells are spread from one
body part to another through lymphatic or circulatory
systems
• cancer cells migrate to nearby nodes, eg. breast cancer to
axillary nodes - chemotherapy is necessary once metastasis
occurs

38. DIFFUSE LYMPHATIC TISSUE
• not enclosed by a capsule
• consists of reticular connective tissue that contains
lymphatic nodules
• Found in:
- small amounts in almost every organ, especially
mucous membranes that line tracts of body

39. ISOLATED LYMPHATIC NODULES
(B CELLS)
• oval-shaped concentrations of lymphatic tissue
• most are solitary, small, and discrete
• Scattered in lamina propria of mucous
membranes of:
- gastrointestinal tract
- respiratory airways
- urinary and reproductive tract

40. ISOLATED LYMPHATIC NODULES
(B CELLS) (cont.)
• when activated by antigens they differentiate into
plasma cells and produce antibodies against specific
antigens
• plasma cells secrete IgA antibodies
- provide protection against bacterial and viral
infections in lumen of tracts

41. ISOLATED LYMPHATIC NODULES
(B CELLS) (cont.)
• located in mucus membranes of gastrointestinal tract
• Examples:
- tonsils
- ileum of small intestine (Peyer’s patches)
- appendix

42. TONSILS
• Aggregations of large lymphatic nodules
• Embedded in mucous membrane
• Located beneath epithelium of pharynx and oral cavities
• Protect nasal and oral cavities
• Three types:
- Nasopharyngeal tonsils
- Palatine tonsils
- Lingual tonsils

44. NASOPHARYNGEAL TONSILS
• Commonly called adenoids
• Located:
- Behind nose
- On roof of posterior wall of pharynx
- Posterior opening of nasal cavity

45. PALATINE TONSILS
• Usually referred to as the “tonsils”
• Location:
- Back of mouth
- Lateral walls of pharynx
• Most commonly removed - tonsillectomy

46. LINGUAL TONSILS
• Base of tongue
• First line of defense from exterior

47. SPLEEN
• Largest lymphatic organ
• Located in upper left abdominal quadrant
• Between fundus of stomach and diaphragm
• 5-6 inches long, 2-3 inches wide
• Resembles a large lymph node
• Filters blood

49. STRUCTURE OF SPLEEN
• Capsule
- covering of dense connective tissue
• Hilum
- depression on medial surface
- nerves and arteries enter spleen, veins and
lymphatic vessel exit

50. STRUCTURE OF SPLEEN
(cont.)
• Trabeculae
- extensions of capsule, form partitions within the
spleen
• Pulp
- tissue inside
- divided into red and white

51. WHITE PULP
• consists of lymphatic tissue
• mostly lymphocytes arranged around central arteries

52. RED PULP
• Consists of:
- venous sinuses filled with blood
- cords of splenic tissue
consists of red blood cells, macrophages,
lymphocytes, plasma cells, and granulocytes

53. FUNCTIONS OF SPLEEN
• Phagocytosis of bacteria and worn out or damaged red blood cells
and platelets
• Stores and releases blood in times of demand, e.g., hemorrhage
• Functions in immunity as a site of B cell proliferation into plasma
cells
• Does not filter lymph because it has no afferent lymphatic vessels
or lymph sinuses

55. THYMUS GLAND
• two-lobed organ
• located in upper part of chest along trachea
• inferior to thyroid gland, posterior to sternum
• largest and most active during prenatal period and
infancy
• after puberty it decreases in size

57. THYMUS GLAND (cont.)
• composed of lymphatic tissue
• subdivided into lobules
• immature T cells originating in the bone marrow
migrate to thymus via blood
• in thymus, cells develop into mature T cells for
release into circulation
• thymic hormones aid in maturation of T cells

58. THYMUS GLAND (cont.)
• mature T cells travel to lymph nodes, spleen, and
diffuse lymphatic tissues where they reside
• responsible for cell-mediated immune responses

59. REMOVAL OF THYMUS
(THYMECTOMY)
• can be removed but decreased T-cell production
results
• possible acute susceptibility to infection

60. REMOVAL OF SPLEEN
(SPLENECTOMY)
• can be removed
• other organs, e.g. the liver and bone marrow can
compensate for it
• increased susceptibility to disease may result

61. DISORDERS OF LYMPHATIC
SYSTEM
• The lymphatic system may not carry out its function
adequately due to
• Blockage (obstruction): Obstruction in the
lymphatic system leads to an accumulation of fluid (
lymphedema). Obstruction may result from scar
tissue that develops when the lymph vessels or nodes
are damaged or removed during surgery, by radiation
therapy, by injury, or in tropical countries, by
infection with a threadworm (filariasis) that blocks
the lymphatic ducts.

65. CONTD..
• Infection: Infection may cause
swollen lymph nodes because the lymph
nodes are inflamed. Sometimes the lymph
nodes themselves may become infected (
lymphadenitis) by organisms that spread
through the lymphatic system from the
original site of infection.

67. Granulomatous lymphadenitis

68. CONTD…
• Cancer: Tumors may block the lymphatic
ducts or may travel (metastasize) to lymph
nodes near a tumor, interfering with flow of
lymphatic fluid through the node. Rarely, a
tumor (lymphangiosarcoma) may develop in
the lymphatic system.

70. THANK YOU