DISCUSSION
We report two observations of disseminated TB with digestive damage
revealed following an inappropriate prescription of corticosteroid
therapy in the context of inflammatory ileo-colitis. In Madagascar, it
is still very difficult to differentiate intestinal tuberculosis from
Crohn’s disease due to lack of technical facilities and insufficient
resources of patients. We retain that intestinal tuberculosis should be
systematically mentioned first in endemic countries in the event of
inflammatory ileo-colitis. Prescribing immunosuppressants is dangerous
in this situation, and should only be prescribed after formal
elimination of tuberculosis.
ITB is an extra-pulmonary form of tuberculosis, secondary to
hematogenous dissemination, or by local extension following peritoneal
involvement or endogenously from swallowed bacilliferous sputum in
patients with active pulmonary forms.1, 8, 9 Its
frequency is estimated at 3 to 5%.1, 2 Abdominal
tuberculosis mainly affects young adults with a peak frequency between
21 and 45 years. The predominance of women has been observed in
countries endemic to TB. Tuberculous involvement mainly concerns the
ileum, the ileocecal junction and then the colon.1,
8-10 CD remains a very rare disease in Africa, especially in
sub-Saharan Africa.3, 4 In order of frequency, ITB
should be mentioned before CD in an endemic TB zone in the event of
inflammatory ileo-colitis.3
Confusion between ITB and CD poses a real diagnostic problem and a very
high diagnostic error rate ranging from 50 to 70%, causing inadequate
prescription of corticosteroid therapy. This similarity concerns all
aspects of these diseases, clinico-radiological, endoscopic and even
histopathological.1, 2, 3 Clinical, radiological and
endoscopic criteria have been established by certain authors but they
are disappointing.1, 3 The presence of ascites remains
more frequent in the course of TB and has been judged as a more specific
clinical criterion in favor of the latter.11
Endoscopic differentiation in colonoscopy between ITB and CD is
difficult since both diseases can present with mucosal ulcers, apthous
ulcers and pseudo-polyps.12, 13 In the literature,
caseous necrosis and the presence of acid-alcohol-resistant bacilli to
Ziehl and Nielsen staining allow a definite diagnosis of TB to be
established, but are seen in 22% and 26-36%
respectively.1, 8, 14, 15 Therefore, currently
available diagnostic confirmation methods have limitations. In our
observations, the absence of ascites, gigantocellular granuloma, caseous
necrosis during biopsy with absence of acid-fast bacilli at the start
misled us and prompted us to erroneously prescribe corticosteroid
therapy. This inadequate prescription of corticosteroid therapy led to
an explosion of TB symptoms. Demory et al had reported a
deceptive case of ITB mimicking CD, leading to inappropriate
prescription of corticosteroid therapy, favoring tuberculous explosion
with tight stenosis of terminal ileum.7 Gargouri etal reported a similar situation where corticosteroid therapy
exacerbated TB disease.6 In our observations,
corticosteroid therapy led to an explosion and dissemination of TB and
allowed us to correct our initial diagnosis. Therefore, it is imperative
to differentiate these two diseases since the immunosuppressants often
used in CD, can lead to an explosion of TB symptoms or even
complications which can be fatal.1, 5, 6, 7Tuberculous ileo-colitis should be ruled out before initiating
corticosteroid therapy to avoid possible tuberculous
complications.1, 6, 7 In our observations,
corticosteroid therapy aroused initially inactive pulmonary TB, with
secondary appearance of a typical pulmonary radiological image and a
positive bascilloscopy. In the literature, this pulmonary involvement
can be seen in 9.87% to 30% of cases of ITB.8-10 The
response to TB treatment confirms diagnosis if in
doubt.6-8 Some authors have even proposed a
therapeutic algorithm for inflammatory ileo-colitis, to make our daily
exercise more practical (Figure 5).3
The management of ITB must be medical and conservative as far as
possible, because of the clinical decline of patients (anemia,
malnutrition and immunosuppression).16 The TB
treatment recommended by the majority of guideline in adults is a daily
treatment in two phases spread over two months of initial quadruple
therapy (Isoniazid, Rifampicin, Pyrazinamide and Ethambutol) followed by
4 to 7 months of dual therapy (Isoniazid and Rifampicin) in
maintenance.1, 16-18 The effectiveness of medical
treatment is judged on the disappearance of fever, ascites and weight
gain in 4-6 weeks.16-19 Surgery should be reserved for
complicated forms.20 Our two patients had received a
6-months medical treatment with satisfactory outcome and were declared
cured at the end of treatment.