[HTML][HTML] Exogenous reinfection as a cause of recurrent tuberculosis after curative treatment

A van Rie, R Warren, M Richardson… - … England Journal of …, 1999 - Mass Medical Soc
A van Rie, R Warren, M Richardson, TC Victor, RP Gie, DA Enarson, N Beyers…
New England Journal of Medicine, 1999Mass Medical Soc
Background For decades it has been assumed that postprimary tuberculosis is usually
caused by reactivation of endogenous infection rather than by a new, exogenous infection.
Methods We performed DNA fingerprinting with restriction-fragment–length polymorphism
analysis on pairs of isolates of Mycobacterium tuberculosis from 16 compliant patients who
had a relapse of pulmonary tuberculosis after curative treatment of postprimary tuberculosis.
The patients lived in areas of South Africa where tuberculosis is endemic. Medical records …
Background
For decades it has been assumed that postprimary tuberculosis is usually caused by reactivation of endogenous infection rather than by a new, exogenous infection.
Methods
We performed DNA fingerprinting with restriction-fragment–length polymorphism analysis on pairs of isolates of Mycobacterium tuberculosis from 16 compliant patients who had a relapse of pulmonary tuberculosis after curative treatment of postprimary tuberculosis. The patients lived in areas of South Africa where tuberculosis is endemic. Medical records were reviewed for clinical data.
Results
For 12 of the 16 patients, the restriction-fragment–length polymorphism banding patterns for the isolates obtained after the relapse were different from those for the isolates from the initial tuberculous disease. This finding indicates that reinfection was the cause of the recurrence of tuberculosis after curative treatment. Two patients had reinfections with a multidrug-resistant strain. All 15 patients who were tested for the human immunodeficiency virus were seronegative.
Conclusions
Exogenous reinfection appears to be a major cause of postprimary tuberculosis after a previous cure in an area with a high incidence of this disease. This finding emphasizes the importance of achieving cures and of preventing anyone with infectious tuberculosis from exposing others to the disease.
The New England Journal Of Medicine