Introduction
Leeches are also known as hirudinea. They are a class of worms that are segmented in nature and are closely associated with aquatic earthworms. The aquatic earthworms are closely related to staying mainly in freshwater. Some of the species of aquatic earthworms can be found in marine waters and also terrestrial places. In the wilderness, getting exposed to leeches is usually seen. They get attached to the bare skin and also sometimes pass through the orifice of the body and may attach themselves internally, too. This state where the leech is attached to the body internally and externally is called hirudiniasis. They are soft but muscular creatures. Their body is flat from one upper end to the other. They can suck from both ends of their body, which is anterior and posterior. The state of attachment known as hirudiniasis may lead to serious morbidity and mortality rarely. Leech envenomation can cause many serious conditions.
What Is a Leech?
The leech is an organism belonging to the annelida phylum and hirudinea class. Almost 600 to 700 species have been studied so far. They are segmented worms that resemble and are similar to the aquatic earthworms. Most of them can be found in fresh waters, but some of them can also be seen in marine and terrestrial environments. The infestation of the leeches generally occurs through unclean or infested water or landmass. They get attached to the surface of the skin, and that is why they come under the characteristics of ectoparasites. Ectoparasites are the kind of parasites that stay on the surface of the host’s body. These types of parasites can cause a skin lesion that is visible to the naked eye. The lesions can be very itchy and may cause discomfort, annoyance, and irritation to the host. They are observed to be hyperendemic in poor, underdeveloped countries and areas.
In rare cases, human endoparasites were also detected. Human endoparasites are the group amongst the family of parasites that stay inside the host’s body and are the pioneer of many diseases, and they cause a condition called mucosal hirudiniasis. Leeches are a variety of organisms that reproduce sexually and are known as hermaphroditic creatures. It is stated that the leeches do not undergo metamorphosis as they get older, and the juvenile leeches can be differentiated from the adults through their size. Some leeches are medicinal and can be used in treating various health conditions.
What Is Leech Envenomation?
Leech envenomation is known as leech bite in a simpler term. The saliva of a leech consists of various substances like hirudin (which is a potential antithrombotic agent), calin (which aggregates the platelets), hyaluronidase, and histamine (a vasodilator). The hirudin is such a component of the leech saliva that it takes a lot of time to wear off. The fibrinogen gets converted into fibrin clots through the process of thrombin-catalyzed conversion, and the effect of it stays for 10 to 20 minutes. The attachment sites of the leech bleed even after they are detached from the surface. Leech envenomation may generally be caused by coming in contact with leech ingested or contaminated water. The leech has an anterior mouth and a posterior mouth. It has sharp teeth-like structures in the anterior mouth that help suck the blood out of the host. As the leech releases anesthetic, it numbs the place of the bite, which makes the recognition of the bite difficult or impossible.
How Is Leech Envenomation Diagnosed?
While diagnosing the leech envenomation, a proper and detailed history should be taken and studied. The suspected person should be asked about any visit near a freshwater body or any exposure to contaminated terrestrial or marine environments.
- The leeches, most of the time, bite and attach externally, but if they get attached to the interior part of the body, the person may suffer from various symptoms such as hematemesis (blood-containing vomiting), epistaxis (bleeding from the nose), hemoptysis (coughing blood), otorrhagia (bleeding from ear), and bleeding from the rectum.
- In the external leech bites, the patient presents with bleeding without pain, bruised surface, itchy lesions, burning sensation, irritation, and redness on the surface of the skin.
- If the leech has entered via the nasal route and infested there, then there can be multiple or recurrent occurrences of epistaxis.In such cases, examination only with anterior rhinoscopy is not sufficient, and examination via endoscope is mandatory.
- If there is rectal leech infestation, then a rectal examination is done with the use of a proctoscope, and if there are symptoms of vaginal leech infestation, then a speculum examination is necessary.
Depending on the seriousness and other factors like age, the examination can be carried out under anesthesia.
What Is the Treatment and Management of Leech Envenomation?
The first step that should be taken in the treatment of leech envenomation includes the detachment or removal of the leech or leeches, controlling the loss of blood, and preventing the host from blood-borne pathogens. To remove the leech from the surface of the skin, various substances are used, such as lidocaine, topical anesthesia, saline, alcohol, turpentine, and heat. The most prominent and effective media was salt water. It helped in the fast removal of the leech from the surface of the skin. Very cautiously, the leech has to be removed to prevent the teeth or the jaw of the leech from staying back at the site of the attachment as it may increase infection or blood loss. After the removal of the leech, the wound should be properly cleaned, and the bleeding should be brought under control and stopped. Topical antibiotic agents such as betadine or any medium containing an alcohol base can also be used to clean the wound.
A pressure at the site of the wound should be created to obtain hemostasis. The pressure can be applied through the bandage or any hemostatic agents. Hemostasis after a leech bite can also be achieved by suturing the wounds, tampons, cauterization, etc. An acid named tranexamic has been used to obtain hemostasis. Prophylactic antibiotics can be prescribed after the exposure of the host to the leeches.
What Is Medicinal Leech Therapy?
Some complementary medicinal methods have a profound and longer history. Nowadays, modern medicos are focussing on the application of complementary medicinal methods in the modern medicinal era. Medicinal leech therapy (MLT) is a technique of olden times, which is studied by various people to know about the medicinal properties of leeches. It is also known as hirudotherapy. It was studied to understand its healing effects in diseases such as inflammatory diseases, post-surgery, etc. Leeches secrete and produce many bioactive substances such as platelet inhibitory factor, antistasin, eglins, hirudin, etc., and they also show other functions such as anti-inflammatory, analgesic, anti-coagulant, antimicrobial effects, etc. This medicinal leech treatment is pocket-friendly and affordable. It is not an alternative way to treat various diseases, but it can be used as a complementary choice, and it comes under multidisciplinary types of treatments.
The leeches are of various types and species, and before using them in medicinal therapy, they should be thoroughly studied. In this medicinal leech therapy, one or many leeches are attached to the skin where the problem exists, and through the medicinal contents of their saliva, the problem is treated. Leech therapy has been used since olden times and has been tested in the times of modern medical times as well. They are used in reconstructive, plastic, and some of the other surgical applications. This therapy is applied in patients with cardiovascular diseases, diabetes mellitus, etc. Not all the species of the leech family are used as medicine, but some of them, like hirudo medicinalis, hirudo quinquestriatus, etc., are used for their medicinal effects.
Conclusion
There are various situations in which leech envenomation can be used. People who benefit from it include those who risk limb amputation because of the side effects of diabetes, those who are diagnosed with heart diseases, and those who will be taking cosmetic surgery. This therapy has also been recommended to treat varicose veins and blood clots. People suffering from anemia, blood-related conditions, or compromised arteries cannot take this treatment. Patients below the age of 18 years old and pregnant women are also suggested to avoid it.
