Leeches are segmented worms that are used in medicinal leech therapy. The European medicinal leech, Hirudo medicinalis, is commonly used. It secretes substances like hirudin that prevent clotting and have anti-inflammatory effects. Leech therapy involves applying leeches to remove congested blood and can help with reattachment of tissue flaps. It has historically been used to treat conditions like joint pain but is still studied for modern uses such as complications from meningitis. Chemical advances like the anticoagulant bivalirudin aim to replicate the effects of hirudin but with fewer side effects than leeches.

1. BY: DEEPAK PATEL

2. 
WHAT IS A LEECH
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TYPES OF LEECHES
BIOLOGICAL SPECIES USED – MEDICINAL LEECH
HABITAT
ANATOMY OF THE LEECH
ADMINISTRATION OF LEECH THERAPY
 Pre Procedure
 Procedure
 Post Procedure

APPLICATIONS
 Historical applications
 Modern uses of leech therapy
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COMPLICATIONS
ADVANCEMENTS
 MECHANICAL LEECH
 CHEMICAL ADVANCEMENTS (BIVALIRUDIN)

3. 
Leeches are
 annelids or segmented worms,
 closely related to the earthworms, are
anatomically and behaviourally more specialized.

4. EUHIRUDINE
-with both anterior and posterior
suckers
Rhynchobdellae
-these are jawless armed with muscular
straw like probiscus and a retractable
sheath
Arhynchobdellae
- These lack a probiscus and which may or
may not have jaws armed with teeth
Gnathobdelae
Glossiphoniidae
-European Medicinal
Leech ( Hirudo
Medicinalis)
Piscicolidae
Pharyngobdellae

5. The medicinal leech or
Hirudo medicinalis is used
therapeutically.
 DESCRIPTION –

 Fully mature adults can be
up to 20cm in length
 are green, brown or
greenish brown
 darker tone on the dorsal
side and a lighter ventral
side
 the dorsal side also has a
thin red stripe.

6. 
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The preferred habitat for this species is
muddy freshwater pools and ditches with
plentiful weed growth.
Most leeches are freshwater animals, but
many terrestrial and marine species occur.

8. 

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PRE PROCEDURE
PROCEDURE
POST PROCEDURE

9. Educate the patient
Obtain informed patient consent
Place order for sterile leeches
Specify how many leeches are required
Specify localized area to be treated & frequency of application
Order baseline haemoglobin & haematocrit
Fax order to pharmacy

10. Physician initiates application of leech to determine desired site of application
Remove leech with a non-toothed forceps
Place in a cup or a syringe with the plunger removed
Clean the site of application &localize the area of application with barrier of gauze dampened
with sterile water
Hold the leech in the cup & steer towards area to be treated

11. After leech detaches drop it in a cup containing 70% alcohol
Never place used leech with unused leech
Place in bags and dispose
Encourage each bite to bleed gently removing locally forming clots
Once sufficient amount of blood is removed, wipe the wound with antiseptic
and cover till bleeding stops

12. 
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Historical applications
Modern uses of leech therapy
 Plastic / Reconstructive Surgery
 Meningococcal purpura fulminans
 Osteoarthiritis

13. 1800’s – High
Demand
129-199 AD
- Galen
200 BC –
Nicader
of
Colophain
End of 19th
Century – Use
began
declining, Ho
wever, in
1884 Haycraft
isolated
Hirudin
1955 –
Hirudin was
finally
isolated and
characterised
.

14. 
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Used to relieve venous congestion
Thus leeches are used to prevent pooling of
blood.
The leech sucks the blood thereby increasing
perfusion of the tissue and maintains tissue
viability until neovascularization occurs.

15. 
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Application of medical leech reportedly
increases blood flow within congested tissue
via active feeding and indirectly by passive
bleeding from the leech bite after
detachment.
Active & Passive bleeding are both facilitated
by the actions of different salivary secretions
of the leech such as hirudin – an
anticoagulant.

16. 24 hours
postoperative
48 hours
postoperative
6 days
postoperative
72 hours
postoperative
2 months
postoperative

17. 
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The most important constituent – hirudin
Other substances which have anaesthetic
action, vasodilator, anti-inflammatory and
analgesic action

18. 
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What is Meningococcal purpura fulminans?
What happens in Meningococcal purpura
fulminans?
How do leeches help in treatment of this
condition?

19. 
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The saliva of the leeches contain a large number of
substances which are found to have antiinflammatory and analgesic properties which have
still not been properly characterized.
It was suspected that the anti-inflammatory and
analgesic agents in leech saliva could be used for the
symptomatic treatment of osteoarthritis.
Currently this hypothesis is being tested.
They have found that there was a rapid pain relieving
effect from the leeches, without any complications.
However, since the treatment is unusual, they could
not compare with any placebo.

20. Aeromonas veronii and
other species of
Aeromonas.
Transfusion of blood may
be required.

21. 

Mechanical Leech
Chemical Advancements (Bivalirudin)

22. A DEVICE TO AUGMENT
BLOOD REMOVAL
AFTER PASSIVE BLEEDING

24. 
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Semisynthetic derivative of Hirudin.
It consists of 20 amino acids formed from
residues 53 to 64 of hirudin with addition of a
sulphated tyrosine at position 63.
Peptide Sequence of Bivalirudin

25. Bivalirudin consists of 3 domains
1) The –COOH terminal domain
2) The –NH2 terminal domain
3) The linker tetraglycine chain

Peptide Sequence of Bivalirudin

26. ACTIVE SITE
EXOSITE 2
EXOSITE 1

28. 
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Bivalirudin inhibits clot bound thrombin as
well as circulating thrombin.
Unfractionated Heparin binds to plasma
protein and therefore is unpredictable.
Low Molecular Weight Heparin binds
comparatively lesser to plasma proteins but
many other disadvantages compared to
Bivalirudin.

29. 
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Hirudin is a 65 amino acid peptide and due to
its larger size may induce immunogenic
reactions (However none are reported as yet)
Plasma half life of Hirudin is 2- 3 hours as
compared to Bivalirudin (30 minutes).
Bivalirudin has 1000 times lower affinity for
thrombin as compared to Hirudin and
therefore is a reversible inhibitor of thrombin.

30. 


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Percutaneous Coronary
Intervention
(Angioplasty)
Acute Coronary
Syndromes
Heparin Induced
Thrombocytopenia
Vascular Brachytherapy
Percutaneous
Peripheral Intervention.

33. 
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Trease & Evans ( Ed.) Pg. 443
Wikipedia –http://en.wikipedia.org/wiki/Leech
MARK D. WELLS, ET. AL. THE MEDICAL LEECH: AN OLD TREATMENT
REVISITED, MICROSURGERY 14:183-186 1993.
A. Eldor, M. Orevi, M. Rigbi The role of the leech in medical therapeutics, Blood Reviews (1996)
10,201-209.
James J. Nawarskas et. al. Bivalirudin A New Approach to Anticoagulation, Heart Disease 2001;3:131–
137
Nicolas W. Shammas, Bivalirudin: Pharmacology and Clinical Applications, Cardiovascular Drug Reviews
Vol. 23, No. 4, pp. 345–360.
Ricky Dippenaar et. al. Meningococcal purpura fulminans treated with medicinal leeches. Pediatric
Care Med 2006 Vol. 7, No. 5 Pg- 476-478.
Claire L. Haycox, MD, PhD. et al. Indications and complications of medicinal leech therapy, Journal of the
American Academy of Dermatology Volume 33. Number 6, Pg. 1053-1055.
Andreas Michalsen et. al. Leech therapy for symptomatic treatment of knee osteoarthritis: Results and
implications of a pilot study Alternative Therapies in Health and Medicine. Aliso Viejo: Sep/Oct 2002. Vol.
8, Iss. 5; pg. 84, 5 pgs.
Nadine P. Connor, et. al. Augmented blood removal after medicinal leech feeding in congested tissue
flaps. Journal of Rehabilitation Research and Development. Vol. 39 No. 4, July/August 2002 Pages 505512
Australian Museum Online –
 http://www.amonline.net.au/factsheets/leeches.html