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Research Article

Meta Analysis of the Leech as a Live Foreign Body: Detection, Precaution and Treatment

Pakistan Journal of Biological Sciences: Volume 12 (24): 1556-1563, 2009

N. Saki, F. Rahim, S. Nikaghlagh and G. Saki

Abstract

Foreign body in the esophagus is a common emergency presentation. Foreign body aspirations comprise the majority of accidental deaths in childhood. Conventional x-ray imaging is usually obtained to aid the diagnosis during the initial evaluation. The decision for surgical intervention is usually based on a suspicious history, physical examination and radiologic findings. Rigid bronchoscopy is very effective procedure for inhaled foreign body removal with fewer complications. Proper use of diagnostic techniques provides a high degree of success and the treatment modality to be used depending on the type of the foreign body is mostly satisfactory. Live foreign body is a rare entity but common emergency presentation. The approach towards a patient with leech infestation comprises a thorough history and systematic examination followed by relevant investigations. However, there is considerable debate over the most appropriate treatment option for such patients. A living foreign body, or parasite, in the oro-or naso-pharynx is rare in Western countries, but in other parts of the world is a fairly common cause of problems. In the past 10 years 28 cases of foreign bodies due to infestation with leeches were treated in our departments. In all patients, 2-70 years old, the complaint was of recurrent episodes of epistaxis, blood-spitting, odynophagia, dysphagia, dyspnea and hemoptysis several days before admission. Examination showed a green-brown mass protruding from different naso- and oro-pharengeal areas, which is in every case, was a blood-engorged leech. Treatment consisted of removing the leech by applying a forceps to the middle of the leech's body and giving a quick pull. Bleeding ceased immediately after removal of the leech. This review aims to develop a comprehensive approach towards patients presenting with foreign body ingestion by developing clinical practice guidelines. These guidelines address not only the initial evaluation of the patient but also the various management alternatives and their advantages, limitations and applicability in various scenarios, based upon a review of the literature.

How to cite this article:

N. Saki, F. Rahim, S. Nikaghlagh and G. Saki, 2009. Meta Analysis of the Leech as a Live Foreign Body: Detection, Precaution and Treatment. Pakistan Journal of Biological Sciences, 12: 1556-1563.

DOI: 10.3923/pjbs.2009.1556.1563

URL: https://scialert.net/abstract/?doi=pjbs.2009.1556.1563

INTRODUCTION

Foreign body in the esophagus is a common emergency presentation. Foreign body aspirations comprise the majority of accidental deaths in childhood (Nikaghlagh and Saki, 2003; Saki et al., 2007). Conventional x-ray imaging is usually obtained to aid the diagnosis during the initial evaluation. The decision for surgical intervention is usually based on a suspicious history, physical examination and radiologic findings (Saki et al., 2008). Rigid bronchoscopy is very effective procedure for inhaled foreign body removal with fewer complications. Proper use of diagnostic techniques provides a high degree of success, and the treatment modality to be used depending on the type of the foreign body is mostly satisfactory (Saki et al., 2009).

Leeches are segmented worms and closely related to earthworms, that have been known as an ecto-parasitism to humans for thousands of years (Uygur et al., 2003). They are blood-sucking hermaphroditic parasites that attach themselves to vertebrate hosts, bite through the skin and suck out a quantity of blood. When leeches feed, they secrete an anticoagulant, which helps them obtain a full meal of blood (Guerrant et al., 2005). However, some cases of endo-partasitism are also seen particularly in rural population. In addition to the classic picture of leeches as an external parasite, these organisms can also reach internal body organs and cavities, including the upper respiratory, esophagus and gastro-intestinal tract (Bergua et al., 1993; Kaygusuz et al., 2001; Ghazzawi et al., 2005). Infestation usually occurs by drinking infested water from quite streams, pools and springs.

Serious complications are expected like dyspnoea, hemoptysis or hematemesis (Bilgen et al., 2002). Reports site of internal infestation include the post-nasal space, nose, larynx, oro-pharynx, vagina, bladder, rectum and hypopharynx (Khan et al., 2004; Labadi and Jamal, 1997; Mohammad et al., 2002; Pandy et al., 2000; Fooanant et al., 2006; Ghimire and Acharya, 2008; Paul and Islam, 2005). Leeches vary in shape from elongated and cylindrical to broad or ovoid. They may be black, brightly colored, or mottled; they have muscular suckers at both their anterior and posterior ends (Stickland, 2000). Their length varies from 5 mm to 45 cm (Guerrant et al., 2005). Many different types of leeches occur worldwide. By attaching to mucous membranes and feeding inside these spaces, leeches cause the clinical syndrome known as internal hirudiniasis.

For over 2000 years, leeches were applied for many disorders as an adjunct to blood letting. In Europe the peak of their use falls between 1830 and 1850, but subsequent shortages led to a decline in their use. Today there is a real clinical application in that they are of great value to plastic surgeons when venous congestion of skin and muscle flaps is a problem (Wells et al., 1993). Medical use of leeches also includes treatment of black eyes and hirudin is used in the treatment of inflammation of the middle ear (Seleznev et al., 1992). Hirudin is also being developed for experimental use as a systemic anticoagulant and may prove useful in in vitro blood sampling.

MATERIALS AND METHODS

Data collection: The literature was primarily searched through some databases: (PUBMED, OVID, EBSCO, WILEY, SCOPUS, COCHRANE. and PROQUEST) using a number of reported cases worldwide. The terms leech, hirudiniasis and foreign body were utilized in the search, to obtain the list of relevant articles. Most of the results came from PubMed (64 articles), while Wiley produced 5 results and the Cochrane database did not reveal any results of significant relevance (Table 1). The articles with relevant and significant findings were then adapted and used in writing this review. The aim of this review was report the leech infestation in past 10 years who were treated in our departments as we as discuss internal hirudiniasis and related differential diagnoses and review medical literature related to this condition.

Pathophysiology: The effects of leech infestation are dependent on the site of lodgment, degree and duration of obstruction. Upper airway involvement varies from complete obstruction with hypoxia and cardio-respiratory compromise to partial obstruction with coughing, wheezing, drooling, stridor and respiratory distress. This pathological condition is extremely rare in urban areas, but endemic in rural regions; and it may have serious, even lethal complications. Leeches generally live in fresh water lakes, ponds or rivers. Much different type of leeches occurs worldwide. Those that attack man divided into two classes: land leeches and aquatic leeches (Guerrant et al., 2005). Land or terrestrial leeches commonly live in tropical rain frost, where they may be found on stones and leaves (Bilgen et al., 2002). Aquatic leeches live exclusively in fresh water. Infesting people drunk from these streams. Leech infestation commonly occurs in low socioeconomic class, particularly in people mostly use cupped palm of their hand to drink water directly from ponds and marshes. Land leeches have powerful jaws that can penetrate the skin in order to attach themselves anywhere on the external surface of the body. They are in contrast to aquatic leeches, which have weak jaws and require soft tissue, such as the mucous membrane of the upper aero-digestive tract, to feed on. Aquatic leeches are rare foreign bodies in the upper respiratory tract (White, 2003).

Diagnosis approach towards patients: Leech has been found in the nose, nasopharynx and oral cavity. The most common mode of presentation is nasal infestation causing intermittent epistaxis and nasal obstruction (Bergua et al., 1993). Fatal dyspnoea, haemoptysis or haematemesis can occur due to endoparasitic infestation (Khan et al., 2004; Iraqi and Squali, 1999). The leeches have been taken with contaminated drinking water and colonized at upper respiratory tract causing difficulty in breathing, respiratory stridor and blood stained saliva (Ghazzawi et al., 2005; Mohammad et al., 2002). Hoarseness of voices, pain and sensation of foreign body in the throat is also possible with leech infestation in the larynx (Mohammad et al., 2002). A leech in the oral cavity usually presents with spitting of blood and a feeling of foreign body as that of present case. Examination under anaesthesia (direct laryngoscopy and pharyngoscopy) is essential and performed as an emergency for diagnosis and removal of the leech.

When a leech is present in the nasal cavity or nasopharynx, patients may present with epistaxis, nasal obstruction and the sensation of a moving foreign body in the nasal cavity. When it is in the oral cavity patients present with spitting blood and the feeling of a foreign body. The presence of a leech in the larynx gives rise to airway obstruction and a change in the voice (Mohammad et al., 2002; Cundall et al., 1986). The diagnosis of a leech as a foreign body may be confirmed after extraction and identification of its species. Therefore, otolaryngologists should pay special attention to patients who have these presenting symptoms and who have a history of recent contact with fresh water lakes or streams (Uygur et al., 2003). The possibility of leech endoparasitism should not be overlooked in patients, especially children, presenting with epistaxis and a history of recent immersion in freshwater lakes or streams in areas where aquatic leeches are commonly found. Diagnosis is easy when a leech is in the nasal cavity. However, when it is lodged in the nasopharynx, examination of the patient under general anesthesia may be required, especially in small children (Bilgen et al., 2002).


Table 1:

Characteristics of included available literatures including technique and patient groups



Fig. 1:

The age distribution in leech infested patients

We retrospectively reviewed 10 years of experience in which 1923 patients (936 adults and 986 children) had undergo foreign body extraction from upper airway, larynx, pharynx and upper end of esophagus, at Imam Khomaini and Apadand Hospitals between January 1999 and October 2008. Out of 1923, only 28 cases (25 adults and 8 children; 11 female and 23 males), with mean age of 26.63 year diagnosed as leech infestation. Sign and symptoms were in decreasing order dysphagia, cough, dyspnoea, hemoptysis and hematemesis. Radiography was done in two projections to neck and thorax just before arrival to the operation room to confirm the site of attachment (Table 2). All patients underwent leech extraction within 4-8 h of admission. All procedures were approved by international guidelines, the Institute Research Ethics and Use Committee of Ahwaz Jondishapour University of Medical Sciences (AJUMS). The age distribution among study group has shown in Fig. 1. On physical examination a black objects were seen in the site of infestation of all patients. The site of infestation was different among all cases.


Fig. 2:

(a) Engorged leech in oropharynx, b removed leech, (b) Live leech in right sided palate

Safe removal approach and management: Techniques for the removal of nasal leeches vary from using forceps for immediate extraction to the use of various substances to tranquilize the leech or relieve pain as the parasite is being removed (Fig. 2a, b) (Kruger et al., 2004; Razi, 2007; Satyawati et al., 2002; Butt et al., 2006; Ağin et al., 2008; García et al., 2002; Tseng and Ho, 2002; Chow et al., 2005; Golz et al., 1989). Removal of leeches from the larynx can be performed by direct laryngoscope, with the patient under general or topical/ local anesthesia. If a leech is in the nares or upper pharynx, it can be detached by applying 30% cocaine, 1:10,000 adrenalin, or dimethyl phthalate to it.


Table 2:

Data about all 28 patients with their symptoms and duration of existence

Another method is irrigation with strong saline, vinegar, turpentine, or alcohol. It is difficult to grasp a leech with forceps because it has a soft and slippery skin, which ruptures easily (Pandy et al., 2000). Firm traction should not be used when pulling a leech off because parts of its mouth may remain behind, leading to continuation of bleeding and secondary infection (Uygur et al., 2003).

Site of infestation: Reported sites of internal infestation include the nose, nasopharynx, larynx, vagina, urethra and bladder, gastrointestinal tract and rectum (Table 3) (Katbab et al., 2006; Shirzadeh, 2005; Alcelik et al., 1997; Aali, 2002; Aribarg and Phupong, 1999; Saha et al., 2005; Uygur et al., 2003). The clinical picture is protean and depends mostly on the exact site of involvement. The nose has been reported to be the most common site of involvement and epistaxis is the most common sign encountered. Laryngeal and hypopharyneal infestation may manifest as an emergency with signs of acute airway obstruction. Anemia, which may be severe and even life-threatening, is a common finding.

The strong attachment of the leech to the mucus membrane combined with its soft and slippery body make it difficult for the medical practitioner to get a good hold of the leech and remove it with force. If the leech is in the nares or upper pharynx, it can be paralyzed with cocaine and extracted directly. A hypertonic sodium chloride solution or lidocaine can also be administered; the former causes the leach to release its hold and the latter paralyses it (Ardehali et al., 2006). Direct laryngoscopy under general anesthesia is essential for both diagnosis and removal of the leech (Bergua et al., 1993). In adults a rapid and careful surgical intervention under local anesthesia may be successful.

After the patient was given a local anesthetic, the object was removed using alligator forceps and a rigid endoscope. Removal was done by applying a forceps to the middle of the leech's body and giving a quick pull (Fig. 3a, b).


Table 3:

Characteristics of included available literatures including site of infestation and worldwide reported cases

Fig. 3:

(a) Applied forceps and leech between the forceps; (b) The leech seen in Fig. 2a: it was 3-5 cm long and dark greenish in color (closer view of the parasite)

DISCUSSION

A leech is rare foreign body in the upper respiratory tract. Leeches generally live in brooks, streams or lakes. When water is drunk from these areas the leeches can infest the human body; they can then be located anywhere in the upper respiratory tract from the nose to the larynx, adhering to the mucus. They may enter the body via the excretory openings of individuals who drink or bathe in infested waters (Makiya et al., 1988; Raza et al., 2006; Gupta, 1980). The nose has been reported to be the most common site of involvement and epistaxis is the most common sign encountered (Al-Hadrani et al., 2000). The presentations of pharyngeal hirudiniasis are sore throat, hematemesis and hemoptysis, sense of having a foreign body, dysphagia and melena. Laryngeal and hypo-pharyngeal infestation may manifest as an emergency with signs of acute airway obstruction (Demiroren and Caliskan, 2003). Anemia, which may be severe and even life-threatening, is a common finding (Litch and Bishop, 2000).

Our patient experienced passive flow of fresh blood into the oral cavity (without a history of vigorous coughing, epistaxis or gastrointestinal symptoms). Painless loss of blood into the oral-nasal cavities of our patients was the result of local analgesic substances secreted by the parasite and its site of attachment at the posterior oropharynx. The strong attachment of the leech to the mucus membrane combined with its soft and slippery body make it difficult for the medical practitioner to get a good hold of the leech and remove it with force. If the leech is in the nares or upper pharynx, it can be paralyzed with cocaine and extracted directly. A hypertonic sodium chloride solution or lidocaine can also be administered; the former causes the leach to release its hold and the latter paralyses it (Ardehali et al., 2006). The leech can then be removed easily. Leech-induced infection is a documented complication of both skin infestation and the therapeutic application of these organisms (Montazeri et al., 2009). However, to the best of our knowledge, there is no report of such infectious complications following internal infestations in the medical literature. Spain was the only European country for which we found cases (four) of this condition reported in the medical literature. Considering this vast geographical distribution and the low socioeconomic status and relatively low sanitation and healthcare services of most of the countries reporting leech infection, the rarity of the condition seems to be a reflection of under diagnosis rather than a true low prevalence. This report highlights the importance of considering leech infestation and other types of parasitic pharyngitis as possible etiologies in pediatric patients presenting with hemoptysis, sore throat and anemia, especially in areas of poor sanitation.

CONCLUSION

Leech infestation should be considered in the differential diagnosis particular in leech-endemic areas. Every attempt should be made to locate the source of bleeding and discomfort sense that does not respond to simple compression. Endoscopic evaluation of the aero-esophagus cavity is mandatory in recurrent of complications, particularly when the cause is not obvious.

ACKNOWLEDGMENT

The authors would like to thank the patients and parents for participating in this study. This study (No.ACRC01) was supported by Ahwaz Jondishapour University of Medical Sciences (AJUMS).

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