Persistent Infection by a Mycobacterium tuberculosis Strain That Was Theorized To Have Advantageous Properties, as It Was Responsible for a Massive Outbreak.
The strains involved in tuberculosis outbreaks are considered highly virulent and transmissible. We analyzed the case of a patient in Madrid, Spain, who was persistently infected over an 8-year period by the same Beijing Mycobacterium tuberculosis strain. The strain was responsible for a severe outbreak on Gran Canaria Island. The case provides us with a unique opportunity to challenge our assumptions about M. tuberculosis Beijing strains. No clinical/radiological findings consistent with a virulent strain were documented, and the in vitro growth rate of the strain in macrophages was only moderate. No secondary cases stemming from this prolonged active case were detected in the host population. The strain did not acquire resistance mutations, despite constant treatment interruptions, and it remained extremely stable, as demonstrated by the lack of single-nucleotide-polymorphism (SNP)-based differences between the sequential isolates. Our data suggest that the general assumption about M. tuberculosis Beijing strains having advantageous properties (in terms of virulence, transmissibility, and the tendency to acquire mutations and resistance) is not always accurate.
Servicio Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias, Spain.
Laura
L
Pérez-Lago
Servicio Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias, Spain CEI Campus Moncloa, UCM-UPM, Madrid, Spain.
Yurena
Y
Navarro
Servicio Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.
Pedro
P
Montilla
Genomics and Health Unit, FISABIO Public Health, Valencia, Spain CIBER Salud Pública, Spain.
Iñaki
I
Comas
Servicio Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias, Spain.
Marta
M
Herranz
Department of Immunology, Hospital Universitario Son Espases, Palma de Mallorca, Spain Research Institute of Health Sciences, Instituto de Investigación Sanitaria de Palma (IdISPa), Palma de Mallorca, Spain.
Carlos
C
Rodríguez-Gallego
Servicio Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias, Spain.
María Jesús
MJ
Ruiz Serrano
Servicio Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias, Spain Departamento de Medicina, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain.
Emilio
E
Bouza
Servicio Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain CIBER Enfermedades Respiratorias, Spain CEI Campus Moncloa, UCM-UPM, Madrid, Spain dgviedma2@gmail.com.
Darío
D
García de Viedma
D001483:Base Sequence; D003141:Communicable Diseases / Q000453:epidemiology* / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D016680:Genome, Bacterial / Q000235:genetics; D005838:Genotype; D006801:Humans; D008264:Macrophages / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000145:classification / Q000302:isolation & purification / Q000472:pathogenicity*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D017422:Sequence Analysis, DNA; D013030:Spain / Q000453:epidemiology; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000382:microbiology; D014774:Virulence / Q000235:genetics
D004269:DNA, Bacterial