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Trypanosomiasis in Dog; A Case Report

December 2008
Iranian Journal of Arthropod-Borne Diseases 2(2):48-51

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Cornell University

Trypanosoma are extra-erythrocytic, protozoan parasites of domestic and wild animals. It is transmitted by biting flies and a cause of fever, anemia, myocarditis and corneal opacity. In the present study, Trypanosoma infection is reported in a male bull dog of two years age at Lahore, Pakistan. Clinical signs and symptoms of infection are recorded. Confirmation of case was done by microscopic examination of Trypanosoma organism in thick blood smear. Furthermore, their effect on certain hematological parameters was studied and concluded that there was decrease of hemoglobin (Hb) concentration and packed cell volume (PCV) while erythrocytes sedimentation rate (ESR) was increased in the infected dog. The animal was successfully treated with single dose of diminazene diaceturate at the dose rate of 3.5 mg/kg body weight, intramuscularly along with the supportive therapy.

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Iranian J Arthropod-Borne Dis, (2008), 2(2): 48-51 A Rashid et al: Trypanosomiasis in…

Case Report

Trypanosomiasis in Dog; A Case Report

*A Rashid 1, K Rasheed 2, A Hussain 1

1Veterinary Research Institute, Ghazi Road Lahore Cantt, Pakistan

2University of Veterinary & Animal Sciences, Lahore, Pakistan

(Received 19 Nov 2008; accepted 12 May 2009)

Abstract

Trypanosoma are extra-erythrocytic, protozoan parasites of domestic and wild animals. It is transmitted by biting

flies and a cause of fever, anemia, myocarditis and corneal opacity. In the present study, Trypanosoma infection is

reported in a male bull dog of two years age at Lahore, Pakistan. Clinical signs and symptoms of infection are re-

corded. Confirmation of case was done by microscopic examination of Trypanosoma organism in thick blood smear.

Furthermore, their effect on certain hematological parameters was studied and concluded that there was decrease of

hemoglobin (Hb) concentration and packed cell volume (PCV) while erythrocytes sedimentation rate (ESR) was

increased in the infected dog. The animal was successfully treated with single dose of diminazene diaceturate at the

dose rate of 3.5 mg/kg body weight, intramuscularly alongwith the supportive therapy.

Keywords: Trypanosoma, Dog, Pakistan

Introduction

Trypanosomiasis is a hemoprotozoan

disease of domestic and wild animals, spread

by biting tabanid flies. The disease is gener-

ally acute and fatal in canines (Soulsby 1982)

and a cause of fever, anemia, myocarditis and

corneal opacity.

Trypanosomiasis has been reported for

the past 70 yr in a number of populations of

opossums, wood rats, raccoons, armadillos

and coyotes (Olsen et al. 1964, Burkholder et

al. 1980, Grogl et al. 1984, John and Hoppe,

1986, Barr et al. 1991, Telford and Forrester

1991, Karsten et al. 1992).

All species of Trypanosoma, with the

exception of some strains of T. vivax which

produce a hyper acute and acute infection, char-

acterized by high parasitaemia, fever, severe

anemia and hemorrhages on the mucosal and

serosal surfaces (Urquhart et al. 2002).

Trypomastigote form of trypanosoma

enters host cells soon after infection, multi-

plies sub clinically, escapes the immune sys-

tem and spread throughout the body pri-

marily within macrophages. Parasitaemia de-

velops within a few day and peaks 2 to 3

weeks post infection, coinciding with clini-

cal disease (Barr et al. 1991). Anemia is a

cardinal feature of the disease in which red

blood cells are removed from the circulation

by the expelled mononuclear phagocytic sys-

tem. Later, in infection of several months du-

ration, when the parasitaemia become low and

intermittent, anemia may resolve to a variable

degree (Urquhart et al. 2002).

There are a number of effective trypano-

somacidal agents for dogs including suramin,

quinapyramine and diminazene but single dose

of diminazene diaceturate is effective in elimi-

nating the natural trypanosomiasis infection

in canine (Rani and Suresh 2007).

*Corresponding author: A Rashid, Tel: +92 42

9220136, E-mail: dr_asif_rasheed@hotmail.com

Iranian J Arthropod-Borne Dis, (2008), 2(2): 48-51 A Rashid et al: Trypanosomiasis in…

The present report describes a case of

trypanosomiasis in a dog, its effect on some

blood parameters and treatment with dimina-

zene diaceturate.

History of case

A male bull dog of two years age was

brought to a private clinic at Lahore, Paki-

stan with history of anorexia, dullness and

persistent fever for three days. On clinical

examination, there was high rise of rectal

temperature (40.8 oC), pale mucous mem-

brane, bilateral lacrimation and generalized

debility. The dog was tested for the presence

of hemoparasites through blood smears (Coles

1986). For this purpose, hair was clipped from

the outer surface of the pinna of ear near the

margin. The marginal ear vein was pricked

with sharp sterilized needle after disinfection

with methylated spirit. A drop of blood was

place on a clean glass slide and smear was

made and air-dried. The smear was stained

with the Giemsa stain (Coles 1986) and ex-

amined under light microscope by using the

immersion objective. Microscopic examina-

tion revealed the presence of Trypanosoma

organism outside the RBC’s.

Hematological and therapeutical study

After confirmation of Trypanosoma

through blood smear, hematological exami-

nation included hemoglobin estimation (Hb),

packed cell volume (PCV) and erythrocytes

sedimentation rate (ESR) using the methods

as described by Benjamin (1978) was carried

out to check the severity of disease. For this

purpose, ten ml of blood was collected from

cephalic vein in heparinized vacutainer tube

containing anti-coagulant.

Simultaneously, treatment of dog with

trypanosomiasis was carried out with dimina-

zene diaceturate at dose rate of 3.5 mg/kg body

weight intramuscularly along with supportive

therapy including oral preparation of liver

tonic (Hepamerz) and vitamin E for 5 d.

Discussion

Clinical signs and symptoms

There is limited published literature avail-

able regarding the prevalence of trypano-

somiasis in dog in Pakistan. In the present

study, microscopic examination revealed the

presence of Trypanosoma organism outside

the RBC’s (Fig. 1). The reported clinical signs

and symptoms were high rise of temperature

(40.8 oC), pale mucous membrane, bilateral

lacrimation, and generalized debility. These

observations were in agreement with the find-

ings of Rani and Suresh (2007) who reported

T. evensi organism in peripheral blood with

history of in appetence, dullness and persis-

tent fever since five days but the same au-

thors also observed bilateral corneal opacity

which is a characteristic finding in chronic

trypanosomiasis (Thirunavukkarasu et al. 2004).

Hematological and therapeutical study

Hematological examination included Hb,

PCV and ESR were carried out and con-

cluded that there was decrease of Hb and PCV

while ESR was increased in the infected dog

(Fig. 2).

Fig. 1. Blood smear showing abnormalities in

erythrocytes with Trypanosama parasites

Iranian J Arthropod-Borne Dis, (2008), 2(2): 48-51 A Rashid et al: Trypanosomiasis in…

Hb (g/dl) PCV (%) ESR (mm/hours)

Fig. 2. Blood Picture in canine trypanosomiasis

The results of the present study are in

accordance to Kjos et al. (2008) who studied

clinical hematology of canine chages disease

in Texas and reported hypoproteinemia, hy-

poalbuminemia, anemia (decrease packed

cell volume) and thrombocytopenia.

Diminazene diaceturate given IM once

at a dosage of 3.5 mg/kg was effective for try-

panosoma infections in dog and animal showed

good clinical improvement after treatment.

Supportive therapy was continued for 5 d. Si-

milar results were observed by Rani and Suresh

(2007) who treated trypanosomiasis in Pom-

eranian dog with a single dose of diminazene

aceturate.

In conclusion, clinical signs and symp-

toms along with the microscopic examina-

tion of Trypanosoma organism through pe-

ripheral blood smear suggested the case of

trypanosomiasis. However, it was difficult to

distinguish the species of Trypanosoma at cli-

nic so there is need of serological and mo-

lecular tests for the diagnosis of species of

Trypanosoma in Pakistan. Moreover, it was

also concluded that single dose of dimina-

zene diaceturate successfully treated the dog

with trypanosomiasis.

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