An eternal microbe: Brucella DNA load persists for years after clinical cure.
BACKGROUND
Despite the continuing high incidence of brucellosis, vague aspects of pathophysiology, diagnosis, and treatment continue to exist, particularly with regard to the ability of Brucella species to survive inside the host.


METHODS
A quantitative real-time polymerase chain reaction assay was used for monitoring bacterial DNA load in brucellosis-affected patients throughout different disease stages. Three or more specimens per patient were obtained (1 at diagnosis, 1 at the end of treatment, and at least 1 during the follow-up period) from 39 patients with acute brucellosis.


RESULTS
The majority of patients (87% at the end of treatment, 77% at 6 months after treatment completion, and 70% at >2 years after treatment) exhibited persistent detectable microbiological load despite being asymptomatic. The 3 patients who experienced relapse did not exhibit any statistically significant difference in their bacterial load at any stage of disease or during follow-up.


CONCLUSIONS
Brucella melitensis DNA persists despite appropriate treatment and apparent recovery. This finding offers a new insight into the pathophysiology of the disease: B. melitensis is a noneradicable, persisting pathogen.
Vrioni
Georgia
G
Department of Microbiology, Medical School, University of Ioannina, Ioannina, Greece.
Pappas
Georgios
G
Priavali
Efthalia
E
Gartzonika
Constantina
C
Levidiotou
Stamatina
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D017347:Brucella melitensis / Q000235:genetics*; D002006:Brucellosis / Q000188:drug therapy / Q000382:microbiology*; D004269:DNA, Bacterial / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial