Related Experiment Video
Updated: Feb 14, 2026

The MODS method for diagnosis of tuberculosis and multidrug resistant tuberculosis
Published on: August 11, 2008
Prevalence and risk factors of drug-resistant extrapulmonary tuberculosis
Viboon Boonsarngsuk1, Khattiya Mangkang1, Pitak Santanirand2
1Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Background:
Physicians are usually aware of the occurrence of drug-resistant (DR) pulmonary tuberculosis (PTB), but lack concern about DR-extrapulmonary TB (EPTB). Data regarding the prevalence and risk factors of DR-EPTB remain limited.
Objectives:
To determine the prevalence and risk factors of DR-EPTB.
Methods:
A retrospective study was performed in patients who had culture-proven Mycobacterium tuberculosis (MTB) from various specimens between January 2013 and December 2015. Patients were classified into three groups: PTB, EPTB and concomitant PTB and EPTB (PTB + EPTB). Clinical data, chest radiographic extent of disease and patterns of DR were collected.
Results:
There were 1014 culture-proven MTB specimens (716 pulmonary specimens and 298 extrapulmonary specimens) from 986 patients (648 PTB, 218 EPTB and 120 PTB + EPTB). The prevalences of isoniazid-, rifampicin- and multidrug-resistant EPTB were 7.8%, .5% and .5%, respectively, which were lower than those of PTB. When PTB and EPTB coexisted, a higher rate of DR-TB was observed than for PTB alone. Of 338 EPTB patients, the extent of radiographic disease was associated with isoniazid-, rifampicin- and multidrug-resistant TB. Previous history of TB and use of steroids/immunosuppressive drugs were also associated with rifampicin- and multidrug-resistant TB in multivariate analysis.
Conclusions:
The prevalence of DR-EPTB was high in patients who had concomitant PTB. Although the prevalences of rifampicin- and multidrug-resistant TB were low in isolated EPTB, the prevalence of isoniazid-resistant TB remained high. Therefore, drug susceptibility testing should be performed in EPTB patients, especially those who carry the aforementioned risk factors.
More Related Videos
Related Concept Videos
Drug Toxicity: Risk factors
Factors Affecting the Risk of Infection
The integrity and count of the white blood cells help the body resist pathogens and fight infection. When impaired, it reduces the body's resistance to pathogens. The acidic pH levels of the gastrointestinal, genitourinary tracts, and skin...
Prevalence and Incidence
Prevalence indicates the proportion of individuals in a population who have a specific disease or health...
Factors Affecting Protein-Drug Binding: Drug-Related Factors
One crucial factor in drug-protein binding is the drug's lipophilicity or its affinity for fat. More lipophilic drugs tend to have higher binding extents. For example, highly lipophilic drugs like cloxacillin exhibit substantial protein binding, with as much as 95% of the drug binding to proteins. In...
Factors Affecting Drug Distribution: Miscellaneous Factors
Age plays a significant role due to differences in body composition among different age groups. Infants, for instance, have a higher proportion of total body water and lower albumin levels, a protein that binds drugs in the bloodstream. This unique composition in infants enhances the...
Factors Affecting Protein-Drug Binding: Patient-Related Factors
Age stands as a key determinant in protein-drug binding. Neonates, characterized by low albumin content, experience heightened concentrations of unbound drugs such as phenytoin and...

