Abstracts
Problems of TB management in London.
Effective TB management in London has been compromised by the failure to match
increasing notifications with increases in nursing and medical resources.
The consequent need to prioritise activity has lead to compromises in services
provision. In one high prevalence borough nurses have had to abandon new
entrant screening to focus on patient support and contact screening.
Consultant clinic appointments must also be rationed in order to maintain
a fast referral system for new patients.
Case management problems are further compounded by the socio-economic problems
associated with patients living in inner city boroughs.
Vitamin D deficiency and Vitamin D receptor polymorphisms
as risk factors
for TB among Gujarati Indians.
The notification rate of TB amongst Gujarati Asians in
Harrowis as high as
809/100000 amongst those who arrived in the UK within the
last 5 years;
this suggests that their is an acquired immunodeficiency
associated with
immigration. In our study of 103 untreated Gujarati TB
patients and 116
Gujarati household contacts, serum
25-hydroxycholecalciferol (25-OH Vit D)
was low in all subjects. Vit D deficiency was associated
with active TB (OR
2.91, 95% CL 1.3-6.5, p= 0.008), and an undetectable 25-OH
Vit D (< 7
nmol/l) level carried a higher risk (OR 9.88, 95% CL
1.3-76.2, p = 0.009).
Although there was no independent association between Vit D
receptor
genotype and TB, the combination of genotype TT/Tt and
25-OH Vit D
deficiency was associated with disease (O.R 2.8, 95% C.L.
1.2-6.5) and the
presence of genotype ff or an undetectable 25-OH VitD level
was strongly
associated with disease (O.R 5.1, 95% C.L. 1.4-18.4).
These findings indicate that Vitamin D deficiency may
account for some of
the increased risk of TB in immigrants; if so, it would be
easily
preventable.
Dr. John Moore-Gillon
TB in London
There are more cases of TB in London than any other European city. Cases
of TB in London have risen by over 80% in the past 15 years. They now make
up 40% of all cases of TB in England and Wales and 50% of drug-resistant cases.
Management of TB in London is complicated by a number of factors:
Over 90 different countries of birth are reported by London TB cases in 1998,
and in some parts of the capital almost 10% of the population are asylum
seekers/refugees. Two-thirds of the most socially deprived boroughs in the
country are in London.
TB services in London are currently undergoing re-organisation, but without any
additional resources. In the absence of significant investments in TB
control there can be little optimism about reversing the rising trend of
tuberculosis.
Tuberculosis
in the United Kingdom
The
epidemiology of tuberculosis in the UK has changed considerably in the last two
decades. Having
been largely a disease occurring among older people in the indigenous white
population reflecting infection acquired many years previously, it has become a
disease of younger people in minority populations reflecting more recent
transmission. Since
the late 1980’s reported case numbers of tuberculosis have increased steadily
with substantial increases in urban areas such as London.
The emergence of co-infection with HIV and the occurrence of drug
resistance (including multidrug resistance and outbreaks) have contributed to
the changing epidemiology.
Re-emergence of Mycobacterium bovis
infection in cattle has also led to increased concern.
Control methods, and surveillance, need to be continuously reviewed to
keep up with the changing face of tuberculosis today.
News from the Genome
The genera mycobacteria includes two important human
pathogens
Mycobacterium tuberculosis and Mycobacterium lepra.
The former is
reputed to have the highest annual global mortality of all
pathogens.
Their slow growth, virulence for humans and particular
physiology
makes these organisms extremely difficult to work with.
However the
rapid
development of mycobacterial genomics following the
completion of the
Mycobacterium tuberculosis genome sequence provides the
basis for a
powerful new approach for the understanding of these
organisms. Five
further genome sequencing projects of closely related
mycobacterial
species with differing host range, virulence for humans and
physiology
are underway. A comparative genomic analysis of these
species has the
potential to define the genetic basis of these phenotypes
which will
be invaluable for the development of urgently needed new
vaccines and
drugs. An overview of the current state of
mycobacterial comparative
genomics will be given.
Thirty Years in Tuberculosis: -
The 30 year period, 1970-2000, commenced with the
introduction of
rifampicin but is ending with the highest ever prevalence
of tuberculosis.
We need the humility to admit that we, the biomedical
community, have failed
and our priority is to ask how we can rectify the failure.
I will suggest
that our way forward is to open the doors of our subject to
workers across a
very broad range of disciplines and to abandon the
reductionist biomedical
model for an holistic one that embraces all disciplines
from molecular
genetics to human rights activism. The foundation of TB
Focus and TB Alert
is a significant step in this direction.
'State of the Union' assessment.
Problems in TB Control
Pros National Treatment Guidelines
National Control & Prevention in update
Audit being done. >85% treated by Chest Physicians
Enhanced Surveillance started
Continuous drug resistance monitoring (mycobnet)
Rejoined IUATLD
Cons Lack of TB nurse provision in high incidence
areas (JTC Audit)
No outcome data for country
Poor system for New immigrant/refugee screening
Shortages of BCG, tuberculin, isoniazid
Funding/provision for MDR-TB