Pre-Multidrug-Resistant Mycobacterium tuberculosis Beijing Strain Associated with Disseminated Tuberculosis in a Pet Dog

Abstract

Resistance to isoniazid, ethambutol, and streptomycin was detected in a Mycobacterium tuberculosis strain, belonging to the Beijing family lineage, isolated from two nodule exudates of a Yorkshire terrier with generalized tuberculosis. This report alerts medical practitioners to the risk of dissemination of pre-multidrug-resistant tuberculosis (preMDR-TB) through exposure to M. tuberculosis -shedding pets.

Intracardiac tuberculomas caused by Mycobacterium tuberculosis in a dog

“…Certainly, our patient has suffered from M. tuberculosis infection for over one year as the tuberculoma was first seen in echocardiography almost 12 months before euthanasia. Nevertheless, TB in companion animals is regarded as such a rare condition in Poland that it is very likely to remain misdiagnosed or undetected [ 9 , 10 ]. This happened also in our patient in which TB remained undiagnosed ante mortem despite several visits to different veterinarians over a period of virtually one year.…”

“…Lack of proper ante mortem diagnosis could be partially attributed to an atypical location of the main tuberculous lesions. Typically, TB in dogs affects lungs and regional lymph nodes, however, lesions have been described also in other organs including the central nervous system, spleen, omentum, pancreas, liver, kidneys, testis, pericardium and diaphragm [ 9 , 10 , 16 – 21 ]. So far the only heart abnormalities described in canine TB were grayish-white, circumscribed lesions in the pericarium and serous pericardial fluid [ 9 ].…”

“…Though epidemiological data on canine TB are generally lacking [ 2 ] in many well-developed countries including Poland TB in humans and animals is considered an extremely rare condition and it is seldom numbered among differential diagnoses by veterinarians even if clinical presentation should raise suspicion of this disease. Therefore, TB cases tend to remain misdiagnosed or undetected and medical practitioners are at risk of exposure of pre-multidrug-resistant tuberculosis [ 8 – 10 ]. This report describes an unusual form of M. tuberculosis infection in a dog where massive intracardiac tuberculomas were the main manifestation.…”

Rapid identification of veterinary-relevant Mycobacterium tuberculosis complex species using 16S rDNA, IS6110 and Regions of Difference-targeted dual-labelled hydrolysis probes

“…The remaining isolates belonged to the M. avium complex or to other environmental nontuberculous mycobacteria. No other MTC species were ever isolated in our lab, with the exception of a few M. tuberculosis isolates collected from zoo captive mandrills and a dog (Amado et al, 2006;Botelho et al, 2014). Although a rare event, infection with M. tuberculosis mostly occurs in animals living in close contact with humans, such as pets, pigs, cattle and captive animals (Michel et al, 2003;Mikota et al, 2001;Mohamed et al, 2009;Schmidt et al, 2008;Berg et al, 2009;Chen et al, 2009;Erwin et al, 2004), and reference veterinary diagnostic laboratories should be aware for these infections as they raise important public health concerns.…”

Standing of nucleic acid testing strategies in veterinary diagnosis laboratories to uncover Mycobacterium tuberculosis complex members

“…Tuberculosis is caused by members of the Mycobacterium tuberculosis complex (MTC), a group of closely-related species including: M. tuberculosis (the predominant cause of human tuberculosis); “ M. canettii ” (a very rare MTC biotype); M. africanum (mainly associated to human tuberculosis in Africa); M. pinnipedii (the cause of endemic tuberculosis in several seal species); M. microti (with bank voles and other small rodents as natural hosts, rarely identified from other mammals); M. mungi (associated to tuberculosis in banded mongooses in Botswana); M. orygis (a recently described and less known rare species, with oryxes, waterbucks, and gazelles as potential hosts in Africa, and bovines and rhesus monkeys in South Asia); and M. bovis and M. caprae (the worldwide predominant cause of bovine and goat tuberculosis, respectively, but also causing disease in a wide range of domestic and wild animals, including humans) (Huard et al, 2006 ; Smith et al, 2009 ; Alexander et al, 2010 ; van Ingen et al, 2012 ; Broughan et al, 2013 ; Rodriguez-Campos et al, 2014 ). Although a rare event, infection with M. tuberculosis may occur in animals living in close contact with humans, such as pets, pigs, cattle and captive animals (Erwin et al, 2004 ; Amado et al, 2006 ; Schmidt et al, 2008 ; Mohamed et al, 2009 ; Botelho et al, 2014 ; Rodriguez-Campos et al, 2014 ). Although the differences in their epidemiology, namely geographic distribution and host preferences, virulence traits and antimicrobial susceptibility patterns (Brosch et al, 2000 ), MTC species share more than 99.9% genomic sequence homology, with very low levels of genetic diversity at the nucleotide level, and present identical 16S ribosomal gene sequences (Sreevatsan et al, 1997 ; Mostowy et al, 2005 ).…”