of people with multidrug-resistant tuberculosis (MDR-TB) in the UK are not
completing the recommended course of treatment, data published in the 3 October
edition of Eurosurveillance shows. Treatment
was completed by 71% of patients in 24 months or more, which was below both the
World Health Organization (WHO) and UK targets (75 and 85%, respectively).
“It is important
to continue to monitor treatment outcomes of MDR-TB patients to improve
treatment management policy,” write the authors.
Therapy with a
fluoroquinolone or bacteriostatic drug was associated with better treatment
MDR-TB is defined
as resistance to the key first-line drugs isoniazid and rifampicin. It is a
global health problem and represents a significant threat to efforts to control
the spread of TB.
The annual number
of confirmed cases of MDR-TB in the UK has increased in recent years from 28
cases in 2000 to 58 cases in 2009. During this time there were also eight
confirmed cases of extensively drug-resistant TB (XDR-TB), infections involving
resistance to important second-line drugs.
issued in 2008 recommend that MDR-TB should be treated with a combination of
ethambutol and pyrazinamide, an injectable agent, a fluoroquinolone, and if
necessary, a bacteriostatic drug. The
treatment should last for at least 20 months and be administered by directly observed
There is no recent
UK guidance for the management of MDR-TB. The NICE (National Institute of
Health and Care Excellence) guidelines issued in 2011 did not
cover MDR-TB, instead suggesting that doctors should consult clinicians with
specialism in this area.
It is also currently
unclear how many people with MDR-TB complete the recommended 24 months of
therefore used information gathered via enhanced surveillance to determine the
number and proportion of MDR-TB patients diagnosed between 2004 and 2007 who
completed the recommended course of therapy. They also examined the factors
associated with a successful treatment outcome, loss to follow-up and death.
There were 204
culture-confirmed cases of MDR-TB during the period of analysis. Just over half
the patients lived in London and were male. Most were aged between 15 and 44
years (83%) and were born outside the UK (85%). Only 30% had a previous TB
diagnosis and less than a fifth had a social risk factor for TB (homelessness,
injecting drug use or a history of imprisonment). Just over a quarter had a
co-morbidity. The most common co-morbidity was HIV (16%).
resistance to a median of four drugs. A high proportion of people had
resistance to one (42%) or two or more (24%) second-line drugs.
duration of treatment for people completing therapy was 19 months and
increased from 18 to 23 months between 2003 and 2007.
The most commonly
used drugs were pyrazinamide, moxifloxacin and ethambutol. A median of four
effective drugs were used in the initial regimen, but approximately a fifth of
patients were treated with fewer than four effective agents.
Just over half of
patients (54%) changed at least one drug in their initial regimen at some
point. The most common reasons were side-effects or intolerance.
Only 40% of all
patients and 53% of individuals with known social risk factors were treated
using DOT. The main reasons for not using this strategy were lack of
indicators for poor adherence (40%), treatment as an inpatient (26%) or using
a pillbox as an alternative (11%).
Overall, 71% of
patients successfully completed therapy at month 24 or later.
rate met the EU target of 70% but was still below the WHO target of 75% and the
UK Chief Medical Officer’s action plan goal of 85%,” comment the investigators.
Of the patients
with unsuccessful outcomes, 7% stopped their treatment, 6% died with TB listed
as the cause of death or a factor contributing to mortality, 8% were lost to
follow-up, 3% completed treatment within twelve months and 1% completed
treatment but then relapsed. One person died of a cause unrelated to TB and
nine people left the UK, mainly to resource-poor countries.
demographic factors associated with unsuccessful outcomes included being non-UK
born (p = 0.026), poor treatment adherence (p = 0.019) and a co-morbidity (p =
0.001) such as HIV (p = 0.048).
for these factors, treatment with a fluoroquinolone (OR = 3.09; 95% CI,
1.21-7.88, p < 0.05) or bacteriostatic drug (OR = 4.23; 95% CI, 1.60-11.18,
p < 0.05) were independently associated with successful treatment outcomes.
future MDR-TB population remains similar to our study population, we recommend
that a bacteriostatic drug should be considered an important part of all MDR-TB
treatment regimens in the UK,” write the authors. They stress the importance of
expert analysis of drug sensitivity tests and recommend that efforts should be
made to ensure the continuity of care for patients transferring out of the UK.