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PubMed1992

The use of leeches for treatment of venous congestion of the nipple following breast surgery.

The medicinal leech, Hirudo medicinalis, played a central role in the evolution of medieval and folk medicine. Today, for the first time in history, the leech actually has a real and valuable purpose in medicine as a useful adjunct for the plastic surgeon: It provides relief of venous congestion. For over 2000 years, leeches were needlessly applied for a multitude of maladies as an adjunct to blood-letting. Their use in Europe peaked between 1830 and 1850, however, shortages led to a subsequent decline in leech application. Today there is a real clinical use for leeches which had led to a resurgence in their use in plastic surgery. Plastic surgeons use leeches in microsurgery to salvage congested flaps, whose viability is uncertain due to venous congestion. We present our experience with two patients where leeches were used to treat isolated venous engorgement of the nipple following breast surgery. Leech therapy is painless, well tolerated, and does not result in significant scarring. Prompt initiation of treatment is mandatory and produces dramatic resolution of venous congestion.

Adult↗
PubMed1994

Experiments on the possible role of leeches as vectors of animal and human pathogens: a light and electron microscopy study.

The presence and survival of pathogens inside the gut of leeches were studied by means of light and electron microscopy. In African leeches from Cameroon, blood was serologically positive for human immunodeficiency virus (HIV) and hepatitis B; blood of Hirudo medicinalis bought in German pharmacies contained up to 11 different species of bacteria. In experiments done at low (3 degrees C) and high (22 degrees, 32 degrees C) temperatures, it was shown that ingested red and white blood cells survive for long periods. The time was prolonged to at least 6 months in cases in which the leeches were stored at 3 degrees C. The same effect occurred with pathogens. Bacteriophages (viruses of bacteria) and bacteria persisted in large numbers for at least 6 months in the gut of experimentally infected leeches. Protozoan parasites such as Toxoplasma gondii, Trypanosoma brucei brucei, or Plasmodium berghei were even capable of reproducing inside the gut of the leech. In the case of Plasmodium parasites, this proceeded at low (3 degrees C) and high (22 degrees C) temperatures until all erythrocytes were used up. These parasites survived as long as the erythrocytes and lymphocytes were of good shape, i.e., around 5-6 weeks p.i. Single stages survived longer, especially at low temperatures. However, electron microscopy studies gave no hint of penetration of such pathogens into the unicellular salivary glands, which would initiate a direct transmission. Such transmission, however, is possible--many fish leeches directly transmit several blood parasites--when the leeches are squeezed during skin attachment or when they are manipulated by dropping salt solution on their backs while they are sucking. Consequently, the leech is a potential vector of many pathogens, especially in regions with an endemic spread of human and/or animal pathogens.

Animals↗
PubMed1986

Severe anaemia and death due to the pharyngeal leech Myxobdella africana.

Six cases of pharyngeal leech (identified as Myxobdella africana) are reported from a highland area of North Kenya. Three patients were severely anaemic and one died. There have been sporadic reports of leech infestation of man in East and Central Africa but these reports lack correct identification of the leech. This paper includes a detailed account of the systematics of the leech and of its habitat. The leeches were ingested accidentally by drinking water from two infested water sources. The major symptoms were a feeling of something in the throat, epistaxis and haemoptysis. On examination, pharyngeal blood was a consistent feature although the leech was rarely seen on initial inspection. Examination under anaesthesia was usually successful in locating and removing the leech. Prompt blood transfusion was life-saving in two cases. The water sources were used by both cattle and man; the cattle may also be parasitized by leeches. Methods of improving the water sources were discussed with community leaders.

Adolescent↗
PubMed1993

Bacteriological investigation of the occurrence and antibiotic sensitivities of the gut-flora of the potential southern African medicinal leech, Asiaticobdella buntonensis (Hirudinidae).

The lack of availability of medicinal leeches is a major impediment to the widespread use of leech therapy for treatment of congested flaps and replants in southern Africa. An investigation into the suitability of an alternative leech, the indigenous southern African leech, Asiaticobdella buntonensis, was therefore started. The risk of hospital-acquired infection related to the use of leeches and the antibiotic sensitivities of bacteria isolated from the gastro-intestinal tract of wild-caught leeches were investigated. Eleven bacterial genera were isolated but Aeromonas were most frequently isolated, occurring in 82% of microbiological samples. All were sensitive to cefotaxime and amikacin. The gut-flora and their sensitivities to 19 antibiotics were similar to those reported for the traditional medicinal leech, Hirudo medicinalis. These results emphasize the need to anticipate unusual infections when prescribing prophylactic or curative antibiotics in the course of leech therapy.

Aeromonas↗
PubMed2001

Evidence for an endocannabinoid system in the central nervous system of the leech Hirudo medicinalis.

In invertebrates, like Hydra and sea urchins, evidence for a functional cannabinoid system was described. The partial characterization of a putative CB1 cannabinoid receptor in the leech Hirudo medicinalis led us to investigate the presence of a complete endogenous cannabinoid system in this organism. By using gas chromatography-mass spectrometry, we demonstrate the presence of the endocannabinoids anandamide (N-arachidonoylethanolamine, 21.5+/-0.7 pmol/g) and 2-arachidonoyl-glycerol (147.4+/-42.7 pmol/g), and of the biosynthetic precursor of anandamide, N-arachidonylphosphatidyl-ethanolamine (16.5+/-3.3 pmol/g), in the leech central nervous system (CNS). Anandamide-related molecules such as N-palmitoylethanolamine (32.4+/-1.6 pmol/g) and N-linolenoylethanolamine (5.8 pmol/g) were also detected. We also found an anandamide amidase activity in the leech CNS cytosolic fraction with a maximal activity at pH 7 and little sensitivity to typical fatty acid amide hydrolase (FAAH) inhibitors. Using an antiserum directed against the amidase signature sequence, we focused on the identification and the localization of the leech amidase. Firstly, leech nervous system protein extract was subjected to Western blot analysis, which showed three immunoreactive bands at ca. approximately 42, approximately 46 and approximately 66 kDa. The former and latter bands were very faint and were also detected in whole homogenates from the coelenterate Hydra vulgaris, where the presence of CB1-like receptors, endocannabinoids and a FAAH-like activity was reported previously. Secondly, amidase immunocytochemical detection revealed numerous immunoreactive neurons in the CNS of three species of leeches. In addition, we observed that leech amidase-like immunoreactivity matches to a certain extent with CB1-like immunoreactivity. Finally, we also found that stimulation by anandamide of this receptor leads, as in mammals, to inhibition of cAMP formation, although this effect appeared to be occurring through the previously described anandamide-induced and CB1-mediated activation of nitric oxide release. Taken together, these results suggest the existence of a complete and functional cannabinoid system in leeches.

Adenylyl Cyclases↗
PubMed1996

Exploring the use of the medicinal leech: a clinical risk-benefit analysis.

The medicinal leech, Hirudo medicinalis, has been used with increasing frequency for salvage of compromised pedicled flaps and microvascular free-tissue transfers. The data pertaining to 18 cases in which flap salvage with leeches was attempted were reviewed and contrasted with the data from 108 published cases from other centers. A further analysis isolated and examined 19 cases in which infection, secondary to leech utilization, supervened. Results suggested that successful salvage of tissue with leeches occurs in 70 to 80 percent of cases. In contrast, the infection rate of most series is between 7 and 20 percent and, when a clinically significant infection occurs, the flap salvage rate drops to 30 percent or less. In addition to infection, the risks of leech therapy include blood loss, which may require replacement transfusion, loss of leeches into body orifices and spaces, allergic reactions, and adverse psychological responses. Clinical indications and contraindications, and strategies to reduce the risks of leech usage, are discussed. Conclusions are that leeches are best used early, and in accordance with an accepted institutional protocol. For each case, the potential risks and benefits must be rigorously assessed and honestly applied.

Adult↗
PubMed1992

Postprandial Aeromonas hydrophila cultures and antibiotic levels of enteric aspirates from medicinal leeches applied to patients receiving antibiotics.

Increasing use of medicinal leeches has been accompanied by increasing numbers of reports of Aeromonas hydrophila infections after leech application on or near damaged tissue. We examined the enteric contents of postprandial leeches after their application to patients receiving antibiotics. We found measurable levels of antibiotic in the leech enteric contents, and in leeches applied to patients receiving an antibiotic effective against Aeromonas hydrophila, there was a significant decrease in positive Aeromonas enteric cultures. Suppression of leech enteric bacteria by antibiotic administration to the patient may be an effective strategy to prevent invasive infection by Aeromonas hydrophila as well as bacterial colonization of devitalized tissue that could be the source of late infection. Clinical studies will be required to clarify whether suppression of leech enteric flora results in a decrease in infections associated with leech use.

Aeromonas hydrophila↗
PubMed2005

Laboratory and field tests of the effectiveness of the lemon-eucalyptus extract, Citridiol, as a repellent against land leeches of the genus Haemadipsa (Haemadipsidae).

Citridiol is an extract of the leaves of Corymbia citriodora (Myrtaceae), the lemon eucalyptus, and mostly consists of p-menthane-3,8-diol isomers. The effectiveness of this extract as a repellent against land leeches of the genus Haemadipsa (Haemadipsidae), primarily H. sylvestris, was tested in the laboratory and field, in Peninsular Malaysia. The formulation tested, Mosi-guard Natural spray, contained 40% (w/w) Citridiol in a base of ethanol, water and isopropanol. In the laboratory test, specimens of H. sylvestris that were placed within moist, untreated arenas enclosed by treated paper rings made numerous attempts to cross the rings but were prevented or delayed from crossing over, in a dose-dependent manner. Mortality was high among the leeches that attempted to cross over the paper rings that had been sprayed to saturation point but low among the leeches that attempted to cross over paper rings that had only been partially treated, with a droplet-spray. The field study was carried out using indices that were formulated to reflect the severity of leech attack and the degree of repellency. Heavy or moderate spraying of footwear and trouser legs (tucked into socks) not only gave complete protection against bites by H. sylvestris and H. picta but also provided high enough repellency to keep the treated footwear virtually free of leeches. Even a light spray greatly reduced the numbers of leeches on footwear and delayed their progression toward biting the test subjects, although it failed to prevent bites completely. There was no decline in the repellency of the Citridiol when hourly assessments were made over a 6-h test period in the field. The results of the study show that Citridiol is highly repellent as well as toxic to leeches, and can be effectively used to prevent leech bites in the field.

Animals↗
PubMed1988

Ingestive behaviour and physiology of the medicinal leech.

Ingestion lasts 25 min in Hirudo medicinalis and is characterized by pharyngeal peristalsis which fills the crop. This peristalsis has an initial rate of 2.4 Hz which decays smoothly to 1.2 Hz at termination of ingestion. During ingestion, the leech body wall undergoes peristalsis which appears to aid in filling the crop diverticula. Body peristalsis begins at a rate of 10 min-1 and decreases linearly to 2 min-1 at termination. The body also undergoes dorsoventral flexions when blood flow is occluded. Blood meal size increases slightly with leech size: 8.4 g for 1-g leeches and 9.7 g for 2-g leeches. However, relative meal size decreases markedly with increasing animal size; from 8.15 times body mass for 1-g to 4.80 times for 2-g leeches. When intact leeches were exposed to micromolar concentrations of serotonin, there was an increase in the rate of pharyngeal peristalsis and the size of the blood meals. Leeches excrete the plasma from their ingested blood meals. Excretion is activated during ingestion, which increases feeding efficiency by increasing the proportion of blood cells in the ingestate. Excretion continues for 4-6 days following ingestion, removing all the remaining plasma from the ingestate. Leech ingestion comprises stereotyped muscular movements, secretion of saliva and excretion of plasma. A strikingly similar feeding physiology is seen in the blood-sucking insect Rhodnius, and we suggest that efficient sanguivory may require the convergent evolution of similar ingestive mechanisms.

Animals↗
PubMed2005

[Effect of the medicinal leech salivary gland secretion on the state of rat subcutaneous mast cells].

It is firstly showed that the medicinal leech salivary gland secretion (SGS) as a polycomponent system of proteins and low-molecular weight substances, activates rat subcutaneous mast cells in vitro prompting a decrease in the heparin saturation index and increasing some characteristic mast cells morphometric parameters. The same mast cell changes were detected by analysis of some specimens of subcutaneous cellular tissue in the point of skin injured by the leech bite. It is shown that these changes are saved during 3 days. The mechanical injury of rat skin does not effect the mast cells activation. Activation of mast cells by SGS is extended to the distant subcutaneous mast cells. It is expressed in sharp decreasing of heparin saturation index although not statistically positive. The secondary leeching on these distant points provokes reduction of mast cells activation and some decrease of post-leeching blood heparin content: 0.154 +/- 0.03 units/ml (n = 10) as compared with post-leeching blood heparin contents analysed from the wound after the primary leeching (0.160 +/- 0.03 units/ml, n = 10). Proceeding from these findings, participation of heparin secreted from activated mast cells in the support of post-leeching bleeding is suggested, the phenomenon which provides unloading of capillary pool by application of medicinal leeches for treatment many diseases.

Animals↗
PubMed1998

Leech therapy for complicated varicose veins.

Several methods of limb bandaging have been described to reduce the oedema and enhance ulcer healing in complicated varicose veins, with varying success rates. Leech therapy has never before been tried for the same. We evaluated the effectiveness of medicinal leech therapy in producing venous decongestion, reversal of oedema, hyperpigmentation and healing of varicose ulcer(s). Whether the leech selectively sucks venous blood was also investigated. Hirudo medicinalis (medicinal leech) was applied to the area surrounding the varicose ulcer(s) in 20 patients with varicose veins with complications and the patients monitored for ulcer healing, and decrease in hyperpigmentation, oedema and limb girth. The partial pressure of O2 (pO2) of 7 patients' arterial and venous blood was compared to that sucked by the leech. After leech therapy all the ulcers showed healing, while 95 per cent of patients showed a decrease in oedema and limb girth. Seventy five per cent patients demonstrated a decrease in hyperpigmentation. The mean pO2 of blood sucked by the leech was 40.05 +/- 7.24 mmHg, which was similar to the mean pO2 of the patients' venous blood (34.33 +/- 8.4 mmHg). Thus it appears from this study that the medicinal leech sucks venous blood and aids ulcer healing, and can probably therefore be used as an effective adjunct in the management of complicated varicose veins. This however requires further evaluation by controlled trials.

Adolescent↗
PubMed2004

Quantitative characterization and classification of leech behavior.

This paper describes an automatic system for the analysis and classification of leech behavior. Three colored beads were attached to the dorsal side of a free moving or pinned leech, and color CCD camera images were taken of the animal. The leech was restrained to moving in a small tank or petri dish, where the water level can be varied. An automatic system based on color processing tracked the colored beads over time, allowing real-time monitoring of the leech motion for several hours. At the end of each experimental session, six time series (2 for each bead) describing the leech body motion were obtained. A statistical analysis based on the speed and frequency content of bead motion indicated the existence of several stereotypical patterns of motion, corresponding to different leech behaviors. The identified patterns corresponded to swimming, pseudo-swimming, crawling, exploratory behavior, stationary states, abrupt movements, and combinations of these behaviors. The automatic characterization of leech behavior demonstrated here represents an important step toward understanding leech behavior and its properties. This method can be used to characterize the behavior of other invertebrates and also for some small vertebrates.

Animals↗
PubMedDate not supplied

Leech therapy for symptomatic treatment of knee osteoarthritis: results and implications of a pilot study.

CONTEXT: Leech therapy was a mainstay in conventional treatment for pain from antiquity until the mid-19th century. Its use is still widespread in traditional healing procedures in Asia, Africa, and Arabic countries. There is renewed interest in leech therapy in the field of complementary medicine and empirical evidence for specific benefit in knee osteoarthritis. OBJECTIVES: To determine the effect of leech therapy as an adjunctive treatment in painful knee osteoarthritis, to investigate the onset of action, to evaluate patients' acceptance of this treatment, and to investigate the side effects of the procedure. DESIGN: Observational, controlled, nonrandomized pilot-study. SETTING: Subjects were inpatients of an academic teaching hospital of the University of Essen, Department of Internal and Integrative Medicine, Essen, Germany. PATIENTS: 16 inpatients (mean age 69 +/- 9 years) with a confirmed diagnosis of osteoarthritis of the knee joint; 10 patients were treated with leeches and 6 served as controls. INTERVENTION: A single trial of 4 leeches (Hirudo medicinalis) applied topically at painful periarticular sites of the knee joint in the experimental group (n = 10). Both groups received conventional treatment for pain with the exclusion of nonsteroidal anti-inflammatory drugs. MAIN OUTCOME MEASURES: Self-reported general knee pain, assessed by visual analog scale for 10 days daily and in a follow-up after 28 days. Frequency of adverse effects also was recorded. RESULTS: Periarticular application of 4 leeches led to rapid relief of pain with sustained improvement after 4 weeks in the absence of major complications. CONCLUSION: Leech therapy may be an effective treatment for rapid reduction of pain associated with osteoarthritis of the knee. Its efficacy should be tested in larger randomized controlled trials with assessment of expectation bias.

Aged↗
PubMed1998

Cholesterol and its derivatives, are the principal steroids isolated from the leech species Hirudo medicinalis.

Steroids were isolated from the blood-sucking leech species Hirudo medicinalis and their structure was studied with one- and two-dimensional NMR spectroscopy (DQF-COSY and HMQC), GC-MS and ESI-MS spectrometry. Fractionating leech lipid using silicic acid chromatography led to the isolation of cholesterol in an early chloroform-eluted peak. Only minor traces of cholest-4-en-3-one, 4 beta-methylcholesterol, and sitosterol were present. The subsequent acetone-eluted fraction contained steroidtriols that were further purified by preparative TLC; these included cholest-7-ene-3,5,6 triol, cholest-4,7-diene-3,6,15 triol and to a lesser amount, cholestane-3,5,6 triol. A developmental study on cholesterol content in the leech showed that it is also the principal steroid in embryonic and freshly hatched leeches prior to feeding. The abundance of cholesterol, comprising approximately 5% of the total leech lipid, suggests that H. medicinalis, a blood sucking leech, has adapted itself fully to its mammalian host in terms of its steroid content. It remains to be seen whether lipids are directly transferred from the host to the parasite or whether leeches have evolved mechanisms to synthesize their own steroids.

Animals↗
PubMed2004

A simple method for the control of medicinal leeches.

The medicinal leech, Hirudo medicinalis, has been widely used in the salvage of microvascular free flaps. Numerous publications have detailed the biology, use, benefits, and risks of leech therapy. One reported significant risk is the risk of leech movement or migration from the surgical site, possibly into body orifices or even deeper into the wound itself. The authors report a simple method of limiting the movement of medicinal leeches from the surgical site, namely, affixing one end of a surgical suture to the leech and tying the free end to a firm object or dressing. This simple method limits the potential range of movement of the leech and reduces the risk of leech migration to unwanted areas.

Animals↗
PubMed2002

Model for intersegmental coordination of leech swimming: central and sensory mechanisms.

Sensory feedback as well as the coupling signals within the CNS are essential for leeches to produce intersegmental phase relationships in body movements appropriate for swimming behavior. To study the interactions between the central pattern generator (CPG) and peripheral feedback in controlling intersegmental coordination, we have constructed a computational model for the leech swimming system with physiologically realistic parameters. First, the leech swimming CPG is simulated by a chain of phase oscillators coupled by three channels of coordinating signals. The activity phase, the projection direction, and the phase response curve (PRC) of each channel are based on the identified intersegmental interneuron network. Output of this largely constrained model produces stable coordination in the simulated CPG with average phase lags of 8-10 degrees/segment in the period range from 0.5 to 1.5 s, similar to those observed in isolated nerve cords. The model also replicates the experimental finding that shorter chains of leech nerve cords have larger phase lags per segment. Sensory inputs, represented by stretch receptors, were subsequently incorporated into the CPG model. Each stretch receptor with its associated PRC, which was defined to mimic the experimental results of phase-dependent phase shifts of the central oscillator by the ventral stretch receptor, can alter the phase of the local central oscillator. Finally, mechanical interactions between the muscles from neighboring segments were simulated by PRCs linking adjacent stretch receptors. This model shows that interactions between neighboring muscles could globally increase the phase lags to the larger value required for the one-wavelength body form observed in freely swimming leeches. The full model also replicates the experimental observation that leeches with severed nerve cords have larger intersegmental phase lags than intact animals. The similarities between physiological and simulation results demonstrate that we have established a realistic model for the central and peripheral control of intersegmental coordination of leech swimming.

Animals↗
PubMed1999

The medicinal leech in Jewish writings.

Leeches were widely used for healing throughout antiquity and the Middle Ages. The rabbinic responsa literature acknowledges the use of leeching for the prevention and treatment of certain illnesses, and classic Jewish sources including the Bible, Talmud, and Codes of Jewish Law describe leeches and mention their medicinal use. Although the swallowing of a leech is considered dangerous and may lead to abdominal swelling, the Talmud describes an oral concoction containing leeches in wine for patients with enlarged spleens. It is also documented that engorged leeches placed in salt quickly discharge their blood and can be used again. Modern plastic and microsurgery have rediscovered the medicinal leech, Hirudo medicinalis, to reduce venous congestion. Clearly, the value of this annelid worm lies in its secretion of an anticoagulant known as hirudin, which has several advantages over heparin. One cannot help but marvel at the wisdom and ingenuity of our forefathers.

Animals↗
PubMed2004

Salvage of partial facial soft tissue avulsions with medicinal leeches.

BACKGROUND: Medicinal leeches have been demonstrated to be extremely useful and safe in the salvage of venous outflow compromised tissue, particularly in digit replants and various forms of flaps. OBJECTIVE: To demonstrate the utility of medicinal leeches in the salvage of venous outflow-compromised traumatic soft tissue avulsions in key facial structures. METHODS: A retrospective review of 4 cases involving the external ear, nose, lip, and scalp in which apparent venous outflow compromise was present. Medicinal leeches were applied acutely in each of these 4 cases, salvaging each of the partially avulsed soft tissue segments. RESULTS: Complete or near complete salvage of each soft tissue segment after using medicinal leeches. CONCLUSIONS: Although it is unusual for a partial soft tissue avulsion of the face to require medicinal leech therapy, situations may occur in which there is adequate arterial inflow but inadequate venous outflow. In such cases, medicinal leeches may play a very important role in salvaging the soft tissue segment. This is particularly important in vital structures such as the ear, nose, lip, and eyelid in which acute or secondary reconstruction is complex. EBM RATING: C.

Animals↗