London, May 2 : Health experts have warned that a changing population structure and ongoing migration have increased cases of drug resistant tuberculosis in the UK.
The study showed that the incidence of tuberculosis in England, Wales and Northern Ireland has been on the rise with more than 8000 cases reported in 2006.
Besides this, resistance to antituberculosis drugs has been increasing globally, reports BMJ.
Experts said that of growing concern is the rising transmission of drug resistant tuberculosis among difficult to treat, marginalized groups in urban areas such as London, and the problems this could create for tuberculosis control.
Dr Michelle Kruijshaar and her research team presented the latest trends in resistance to antituberculosis drugs between 1998 and 2005 using data from the National Surveillance System, involving 28 620 confirmed cases of tuberculosis.
By and large, the study showed that the proportion of cases resistant to any first line drug had increased from 5.6 percent to 7.9 percent.
Researchers found an increasing proportion of isoniazid resistance and small increases in rifampicin resistance and multidrug resistance.
Most importantly, the researchers found that outside London there was a major rise in resistance to isoniazid.
They suggest that the findings reflect that the increasing numbers of patients with tuberculosis are not born in the UK.
In fact, analyses showed an increase in the number of cases in people from Sub-Saharan Africa and the Indian subcontinent that could be related.
In London, the increase in isoniazid resistance has been associated with an ongoing outbreak from 1999 that has involved over 300 cases to date.
This outbreak has been linked to imprisonment and drug misuse and includes mainly the UK born population.
The researchers support the importance of recognising symptoms early in this group.
They also found that the proportion of multidrug resistance showed a small increase, with the levels seen in the UK similar to those in other Western European countries, and suggest that most multidrug resistance cases occur due to problems with patient management rather than as a result of transmission within the UK.
The researchers concluded that their findings highlight the importance of early case detection by clinicians, rapid testing of susceptibility to drugs, additional support services to ensure that patients complete treatment, as well as continuous surveillance, and more help with tuberculosis control in countries with high incidence.