Leeches – allies of medicine

These wormy creatures have proven useful in treating certain health conditions and leech farms are being set up in the peninsula and other countries in the region to tap their potential as medical tools for healing

FEEDING TIME: Leeches feeding from a patient’s hand.

MENTION leeches and most people will recoil in horror. These wriggly and slimy cousins of the earthworms not only bite but also suck blood!

The fear of these wormy ‘draculas’ is rooted in the belief — rightly or wrongly — that they can crawl into unlikely places like the nostrils and ears, and cause pain and blood loss. Moreover, their feeding habits cannot be said to inspire confidence — attaching themselves to other animals and even humans and sucking their blood.

But with new discoveries and awareness of the wonders of Mother Nature’s creations and in a back-to-nature approach, scientists, researchers, and professionals are looking at leeches in a new way and even putting their blood-sucking ‘technique’ to good use.

Despite their dreadful reputation, leeches are now recognised to be medically useful to humans and leech farms are being set up in the peninsula and other countries.

To know more about the potential and use of leech therapy in Sarawak, thesundaypost talked to a local doctor and a local academic.

According to Kuching Specialist Hospital consultant anaesthetist, Dr Khairul Faizi Annuar, medical schools in the country do not teach the use of leeches but may touch on by-products like hidurin and related compounds.

He said in local surgery, the drug heparin and other newer generation and more costly drugs were used as anti-coagulants.

“But the leech bite has a local effect (confined to a specific region) compared to a conventional injection of anti-coagulant drug which may lead to bleeding in other parts of the body.

“Other interesting compounds in leeches include pain killers … so leech bites are not necessarily painful.

“Also, unlike mosquito bites, there is no swelling. This shows the presence of anti-inflammatory compounds in leech bites which have minimal side effects compared to the steroids commonly used.”

Dr Khairul agreed the use of leeches for certain medical treatments would be good if it was effective in healing and reducing costs.

He reckoned the use of leech therapy may be cheaper than modern drugs which usually involved costly R&D and clinical tests before being approved by the US Food and Drug Administration (FDA).

“In fact, the FDA has approved an application from French firm Ricarimpex SAS to market leeches for medicinal purposes. Leeches are now considered to be medical tools for healing skin grafts or restoring circulation.

“As for the use of leeches in local surgeries, it’s still not yet recognised because hospital staff may not be comfortable in handling leeches,” Dr Khairul said.

“The guts of leeches contain bacteria which produce antibacteria that kill other bacteria — there may be a risk of infection from leech bites, so we must use medical-grade leeches free of parasitic organisms, clean, sterile and treated properly to prevent contamination,” he added.

Universiti Malaysia Sarawak (Unimas) senior lecturer cum physiologist Dr Noorzaid Muhamad believed the use of leeches in medicine should be explored.

He pointed out that Malaysia should not just depend on foreign countries to do research on leeches since there were already local species rich in hirudin and other useful compounds.

“We should use our own resources to do R&D on leeches in our country but there is little or no research in local universities on leech therapy due to lack of market demand — unlike HIV and bird flu which have created an urgent need for R&D and hence, more money is poured into their research.”

Dr Noorzaid said for leech therapy R&D, he might focus on gout because it was easier to measure and see the results, adding:

“We can analyse the blood from leech bites to trace the major compounds being sucked by it.”

He explained that leech saliva involved in gout treatment may contain compounds that improve blood circulation and reduce swelling, and the uric acid crystals clogging the system and causing inflammation (pain), were probably dissolved and sucked out by the leech.

“Gout would be a clear indicator of the efficacy of leech therapy — from pain to no pain situation — in comparison with arthritis that is more difficult to test.”

Dr Noorzaid believed leeches were not used in local hospitals because of the fear of contamination with microbes or pathogens.

However, in modern times, leeches have found new fame in microsurgery where doctors need the leech’s precision in draining congested blood from wounds.

Plastic surgeons are especially happy to use leeches in the treatment of difficult grafts and reconstructive surgery. Leeches are used to help restore blood circulation to grafted tissues or re-attached fingers and toes.

For example, micro-surgeons in a Boston hospital used leeches to save a five-year-old boy’s ear bitten off by a dog. The leech removed congested blood to allow normal circulation to return to the tissues, thus preventing gangrene.

‘Medical leeches’ are also used in plastic surgery for improving brain circulation and curing infertility.

thesundaypost also spoke to a traditional Chinese medicine (TCM) physician and visited TCM shops in Kuching to find out how the species of leech called sui che in Mandarin is used in traditional medicine locally.

In TCM, leeches are used in dried forms, usually imported from the provinces of Shandong or Jiangxi in China, and the species used is Hirudo nipponica Whitman.

“Dried leeches are considered poisonous like any other drugs, and should only be used with proper prescription,” said Chinese physician Hung Sung Huo of Piles & Laser Acupuncture Centre and Male Physiotherapy Centre.

“The bitter drug is mixed with other herbs, boiled with water, and used for urinary bladder or liver treatment, or for blood circulation in women but it should not be taken by pregnant women,” he added.

In TCM, the drug is considered neutral — neither hot nor cold, and is not suitable for vegetarians since it is of animal origin.

“Live leeches may be used in some of China’s hospitals today, especially for surgeries,” added Hung, secretary of Kuching Life Care Society.

According to Poh Sen Foh medicine shop in Padungan, not all Chinese medicine shops sell dried leeches whose uses are considered rare here.

To find medicinal dried leeches, one would have better luck checking out the Chinese medicine shops along Jalan Carpenter and Jalan Cina.

A shop assistant in Teck Nyen Medical Hall Jalan Carpenter said their customers were mainly Malays who used dried leeches as a libido booster for men. The price is about RM8 per ounce which may have 10 or more dried leeches drained of blood, flat, black on top and brown underneath, and measuring about half-inch by two inches in size.

“The dried leech product from China contains protein components used for liver or urinary bladder and blood circulation purposes,” said Sim Hui Meng, an assistant of TCM shop Buan Choon Tng at Jalan Cina.

She said the medicinal dried leech was usually mixed with other herbs and not used on its own.

“Our customers are mainly Chinese who come with a physician’s prescription — some come from places like Hong Kong or China,” she noted.

This TCM shop has been around for over 100 years and passed down over three generations with many regular customers knowing the shop by name.

Sim observed that the use of medicinal leech was common in West Malaysia but rare in Sarawak.

Today, doctors in Europe and America use leeches to treat many types of ailments like abscesses, glaucoma and painful joints, and to heal venous diseases.

Hundreds of thousands of leeches are sold in America to hospitals, clinics and individuals. But the European market is much bigger — millions of leeches are sold there every year.

Leeches can be ‘milked’ for their secretions without harming them and research is continuing into the possibility of synthetically engineering leech saliva.

The natural compounds may be complex and far too numerous to be economically synthesised for mass production.

The other alternative is to let Mother Nature do her job of manufacturing the complex mix of useful compounds through the breeding of leeches and harvesting them for use in therapies.

Currently, there is a lack in the use of leeches and leech therapy in Sarawak, according to Awang Mohd of a local company called Keringkam Emas Sdn Bhd and he aims to correct the situation.