Study of respiratory symptoms among sputum positive

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Table (33) showed, mean induration oftuberculin test in smear +ve
-»---- 17.5 mm was highly significant than in smear -ve 13.2 mm cases, in this
study +ve tuberculin test in smear -ve cases can be explained as most of
them were BCG vaccinated, or they get infection and diseased.
When clinical symptoms presentation in smear +ve cases were
compared as regard tuberculin test results (tab. 34) no any symptoms was
significantly different, and in agreement with this results Garnal EI Din
(1997) found the same result. Their was non significant association
between tuberculin skin test and smoking among cases with smear +ve or
smear -ve for APB. But tuberculin test positvity was higher in non smoker
79.7% than in smoker 72.2% in smear +ve cases, also Garnal EI Din
(1997) found lower reactivity in smoker than in non smoker and this can be
explained by Sibille and Reynolds (1990) as tobacco smoke could alter
native and acquired resistance to mycobacterial tubercle bacilli, and
exposure to tobacco smoke causes morphological and functional changes in
the alveolus macrophage with multiple defects in macrophage/monocyte
and CD4 lymphocyte immune responses. The smoking recognized as a
toxic factor capable of reducing host defense (Crofton et al., 1992).
In this study their was non significant difference of BCG vaccination
between smear +ve (88.3%) and smear -ve (81.3%) (tab. 36), but
percentage was higher in smear +ve cases than in smear -ve this explained
as BCG has lower degree in protection. Also Altet et al. (1993) concluded
that, the low degree of protection afforded by the BeG vaccination
program, and the known harmful effects it causes, make this method of
little value, and not advisable in tuberculosis programs, also Murhekar et
al. (1995), revealed the similar conclusion that III VIew of the low
protective effectiveness of BeG vaccination against pulmonary
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