Leeches, a blood-sucking parasite, are rarely reported in humans and animals as a cause of many problems. Hirudiniasis is not common in animal and humans; however, sporadic reports of leech infestations in humans and animals are available from the Middle East and adjoining countries. In some reports in human beings, leeches as a parasite in the respiratory tract have been reported, and in animals, leeches infesting the nasal cavity were reported in one camel in Iraq (Al-Ani and Al-Shareefi 1995; Cheikh-Rouhou et al. 2000). The first reported infestation in sheep of L. nilotica in Iran was reported by Bahmani et al. (2006), in which six to seven leeches were isolated from the esophagus. The hemathological signs showed normocyctic normochromic anemia that were the same as the presented case. Some reports from Elam province in Iran have shown L. nilotica in sheep, cattle, dog, and donkey, all of which manifested respiratory disorders and anemia (Mehrzad et al. 2007). Mehrzadi et al. (2009) reported an infestation of L. nilotica in herd dog in Shahrekord province in Iran. That particular case showed 3% anemia and local acute infestation. Another report of L. nilotica was from a 4-year-old cow with acute respiratory distress and continuous profuse bleeding from both nostrils. After removing the leeches from the nostrils and maintaining supportive treatment, the animal died after a few hours (Moghaddar 2010). In this case, however, the leeches were removed carefully by using forceps without the prescription of any drugs. After examination, the species of leech was identified as L. nilotica.
Cundall et al. in 1986 reported laryngeal leeches (Myxobdella africana) in six infants with severe anemia, one of whom died due to severe anemia. The strong jaws and muscular suckers at the anterior and posterior ends can suck the blood of hosts, and this can cause anemia. Stickland et al. in 2000 mentioned that leeches could suck the blood of hosts nine times more than the size of their bodies. They secrete an anticoagulant substance containing hirudin, which inhibits the thrombin, factor IXa, and other enzymes (Will 1988). These anticoagulants enable the leech to feed on its host freely. The saliva of leeches contains enzymes and anti-auglutination substances such as hirodine, antielastaze, antitripsine, and antiplasmine, which cause bleeding and anemia (El-Awad and Patil 1990).
Occasionally, for removing the leeches in humans and dogs, a local or systemic anesthesia is used by using lidocaine 1/10,000, cocaine 30%, diethylphtalate, sulfate atropine (0.04 mg/kg), xilazyne HCL, and ketamine HCL. In the present case, however, a gag was used to remove the leech without using any anesthesia (Uygur et al. 2003; Bani Ismail et al. 2007).
Although some of the literature mentioned that after removing the leeches prescribing ferrous sulfate could help to relieve anemia; in this case, no medication was prescribed (Bani Ismail et al. 2007; Haycox et al. 1995).
The majority of inhabitances of leeches are ponds, lakes, and streams (Mohammad et al. 2002). After the intake of contaminated water, the leech is localized in the upper respiratory system or digestive system. These locations are mostly the nose, nasopharynx, oropharynx, epiglottis, larynx, and upper trachea. Investigations revealed that the animal used to drink water from a nearby pond that had rainwater. The owner of the present case was educated not to allow the other animals to drink water from the infested pond.