الفهرس 
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Abstract
Tuberculosis remains one of the deadliest diseases in the world.
More than 2 billion people (about one-third of the world population) are
estimated to be infected with Mycobacterium tuberculosis. According to
the World Health Organization (WHO), in 2010, 8.8 million individuals
became ill with TB every year, out of which 3 million annual deaths are
due to tuberculosis.
Although, many new diagnostic tools have been developed
recently, for the diagnosis of pulmonary TB, their use is limited to
developed countries because of their cost and technical requirements.
Detection of AFB is still the initial step in the diagnosis of pulmonary
TB, and isolation of M. tuberculosis remains the gold standard in its
diagnosis.
Current diagnosis of pulmonary TB relies on clinical presentation,
supported by laboratory investigations particularly direct smear and
culture method. Direct smear is very fast and cheap method but it is lack
of sensitivity (40-60%), since it relies a lot on the quality of samples and
requires experience technologies to identify the acid fast bacilli. Culture
method is more sensitive but requires longer incubation times. Thus, the
development of a simple, cheap, fast and reliable antibody or antigen
detection assay might be of great benefit for early disease detection and
disease control.
Lipoarabinomannan (LAM) is a lipopolysaccharide which
constitutes one of the dominant antigens of the mycobacterial cell wall.
The particular characteristics of this antigen, which presents repetitions of
D-arabinofuranose residuals, induce strong and extremely pure immune
reactions.
The present study was done to assess the value of serum
lipoarabinomannan in diagnosis of pulmonary tuberculosis. The study
was settled on two groups, the control group which contained 20 normal
persons and the case group which contained 40 patients diagnosed as
having pulmonary tuberculosis whom were diagnosed by spontaneous
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sputum smear(27/40), induced sputum smear(7/40), one of the negative
sputum smear was positive in culturing it on LJ media. 5/40 whom were
negative sputum smear underwent bronchoalveolar lavage 4 of them were
positive by smearing the BAL with ZN stain and one was positive by
culturing on LJ media for mycobacterium tuberculosis. After that culture
have been done to all patients and was positive in all.
All subjects were underwent:
1- Detailed history taking;
Personal history, Patient’s complaints, Present history, Past history
of chest diseases or other diseases, Family history: history of contact to
TB patient, travelling .
2- Clinical examination:
A thorough general and local chest examination were done.
3- Ivestigations:
• Full routine laboratory investigations
• Measure of oxygen saturation (Arterial Blood Gas)
• Electrocardiogram (ECG)
• Roentgenographic examinations.
• Tuberculin skin testing.
• Sputum smears examination: (spontaneous -self inducedsputum
or induced sputum) and BAL were examined for the
presence of acid-fast bacilli (AFB) by Ziehl Nelsen stain and
cultured on Löwenstein–Jensen (LJ) medium
• Lipoarabinomanann LAM ELISA test: LAM was measured
in serum samples of the patients and control groups using
ELISA kit.
The results were statistically analyzes and Case/Control Groups
were well matched across demographic characteristics and showed the
expected significant differences in the ESR, TST, smear and culture
positivity (independent variables).
While Group comparison for key outcome (dependant variablesqualitative
and quantitative serum LAM levels) revealed statistically
significant difference between cases (PTB) and control group.
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The present study revealed that the cutoff point of serum
LAM(0.375) with area under the curve of (0.819) the sensitivity,
specificity, PPV, NPV, and accuracy were 90%, 100%, 100%, 83.3% and
93.3% respectively. And the combination of serum LAM testing and
sputum smear identified 95% of confirmed TB cases.
In the present work febrile illness, hemoptysis, immune competent
state, tuberculin skin test (TST), smear and culture positivity, extensive
radiological lesions and raised ESR were a significant predictors that
associated with positive qualitative serum LAM(P<0.05 ).
The present study revealed that patients with advanced age
(>60year old) , febrile illness, hemoptysis, extensive radiological lesions,
raised ESR, and TST, smear and culture positivity had higher significant
quantitative serum LAM levels than those of contrary group.
The LAM test was noted as simple reliable test for diagnosis of
pulmonary tuberculosis.