Mycobacterium tuberculosis Genotypes in patients developing pulmonary tuberculosis related acute respiratory distress syndrome
Abstract
Background: Acute Respiratory Distress Syndrome is an uncommon but frequently fatal presentation of pulmonary TB. We attempted to identify whether a specific M. tuberculosis genotype occurs more commonly in patients who develop ARDS.
Methods: An observational study carried out at the Aga Khan University Hospital, Karachi, Pakistan enrolled all ARDS patients with tuberculosis. MTB isolates were spoligotyped for strain identification.
Results: 725 patients were admitted with pulmonary tuberculosis during the study period. Only 2.5% (18 patients) developed ARDS. Inpatient mortality rate was 58% (7 patients). Genotypes of M. tuberculosis isolates were predominantly CAS I (58.3%) and Unique strains (25%). Beijing and CAS subfamilies were less common; with each genotype identified in 8.3% patients respectively. All except one of the isolated strains were sensitive to usual first line anti-tubercular drugs.
Conclusion: Our results indicate that the CAS1 strains are the most common genotypic strains causing severe respiratory disease in patients with ARDS.
DOI: http://dx.doi.org/10.4038/sljcc.v2i1.2370
Sri Lanka Journal of Critical Care Vol.2(1) 2011 20-24
Acute
Respiratory
Distress
Syndrome
is
an
uncommon
but
frequently
fatal
presentation
of
pulmonary
TB.
We
attempted
to
identify
whether
a
specific
M.
tuberculosis
genotype
occurs
more
commonly
in
patients
who
develop
ARDS.
Methods:
An
observational
study
carried
out
at
the
Aga
Khan
University
Hospital,
Karachi,
Pakistan
enrolled
all
ARDS
patients
with
tuberculosis.
MTB
isolates
were
spoligotyped
for
strain
identification.
Results:
725
patients
were
admitted
with
pulmonary
tuberculosis
during
the
study
period.
Only
2.5%
(18
patients)
developed
ARDS.
Inpatient
mortality
rate
was
58%
(7
patients).
Genotypes
of
M.
tuberculosis
isolates
were
predominantly
CAS
I
(58.3%)
and
Unique
strains
(25%).
Beijing
and
CAS
subfamilies
were
less
common;
with
each
genotype
identified
in
8.3%
patients
respectively.
All
except
one
of
the
isolated
strains
were
sensitive
to
usual
first
line
anti-tubercular
drugs.
Conclusion:
Our
results
indicate
that
the
CAS1
strains
are
the
most
common
genotypic
strains
causing
severe
respiratory
disease
in
patients
with
ARDS.
© 2011 Nawal Salahuddin, Mahnaz Tanveer, Nisar Rao, Saeed Akram, Zahra Hasan, Rumina Hasan, published by Postgraduate Institute of Medicine - University of Colombo - Sri Lanka
This work is licensed under the Creative Commons License.