This study evaluated the role of atypical pathogens and viruses in acute exacerbations of bronchial asthma (AEBA) in adults and children. The study found that acute infection with Chlamydia pneumoniae or Mycoplasma pneumoniae played an important role in AEBA among adults. However, infection with these atypical pathogens did not contribute to AEBA among children. Additionally, viral infections, such as from influenza, adenovirus, and respiratory syncytial virus, were found to play an important role in AEBA in both adults and children. The study recommends further research to evaluate the therapeutic implications of these findings.

2. The Role of Atypical Pathogens in Acute
Exacerbations of Bronchial Asthma
Gamal Rabie Agmy , MD, FCCP
Professor of Chest Diseases, Assiut University

3. Introduction
Atypical pathogens are recognized as causes of
RTI, but their role in AEBA is not clear. Some
studies found an association between acute
infection with either Mycoplasma pneumoniae
or Chlamydia pneumoniae and AEBA, but
others did not.

4. Introduction
To our knowledge, there was only one study in
which the association between either Coxiella
burnetii or Legionella species and AEBA was
investigated.

5. Aim of Work
The main objective of this study was to evaluate
the rate of acute infections with 4 atypical
organisms
(Mycoplasma
pneumoniae,
Chlamydia pneumoniae, Coxiella burnetii or
Legionella pneumophilla) among adults and
children hospitalized with AEBA compared with
a matched control groups.

6. Aim of Work
Our second aim was to assess the role of acute
viral infections in AEBE in both adults and
children.

7. Patients and Methods
Acute infections with 4 atypical pathogens and
viruses were evaluated in 2 groups of patients
with AEBA, and compared with the
corresponding rate in a matched control group.
The first group of patients included 96 adults
while the second one incorporated 88 children.
Paired sera were tested using microimmunofloresent method to establish the serological
diagnosis.

8. Inclusion Criteria
(1)A past history of typical bronchial asthma;
(2)Reversibility of at least 12% of the FEV1 value with
the patient in stable condition;
(3) No history of smoking
(4) Negation during the hospitalization of causes of
dyspnea other than bronchial asthma;
(5) Ruling out of pneumonia by admission chest X-ray.
(6) No known or suspected immunodeficiency,
hypergammaglobulinaemia, connective tissue disease,
other autoimmune disease ;and positive rheumatoid
factor

9. Patients and Methods
Pneumo-slide (Vircell-slide) was used
for indirect microimmunofluorescent
assay for the simultaneous diagnosis
of the main etiological agents of
AEBA.

10. Table 1: Demographic data of asthmatic patients and
their controls included in this study:
Variable
Asthmatic
adults
Control
adults
Asthmatic
children
Control
children
20–54
39.3 ± 10.5
19–57
37.8 ± 11.7
4–12
8.9 ± 3.6
3–12
9.1± 3.1
64/32
62/34
52/36
47/35
Chronic oral steroid therapy,
%
30
0
15
0
% baseline FEV1 reversibility,
mean ± SD*
20 ±5.3
-
25 ± 4.9
-
ICU admission%
20
0
18
0
Mechanical ventilation %:
Invasive
Non-invasive
8
5
0
0
10
0
0
0
90±6.6
96±2.3
91±5.3
96±1.4
Age: Range
Mean± SD
Male/Female
O2 saturation %,, mean ± SD*

11. Figure 1: Role of Chlamydia in acute exacerbations
of bronchial asthma in adults and children:
25%
20%
Athmatic
15%
Control
10%
5%
0%
Adults
Childern

12. Figure2 :Role of Mycoplasma in acute exacerbations of
bronchial asthma among adults and children:
15%
Athmatic
10%
Control
5%
0%
Adults Childern

13. Figure3 :Role of Legionella pneumophillia& Coxilla Burniti
in acute exacerbations of bronchial asthma among adults
and children:
3%
2%
1%
0%
Athmatic
adults
Control
adults
Legionella
Asthmatic
children
Coxilla
Control
children

14. Table 2:The percentage rate of acute viral infection among
adults with AEBA
Pathogen
Asthma
Control
p Value
Influenza virus type A
18
0
<0.0001
Influenza virus type B
3
0
NS
Parainfluenza virus type 1
5
1
NS
Parainfluenza virus type 2
4
0
NS
Parainfluenza virus type 3
1
0
NS
Adenovirus
11
1
<0.0001
Respiratory syncytial virus
8
0
<0.001
One or more of the above
20
2
<0.0001
Adenovirus& Chlamydia
8
0
<0.001

15. Table 3:The percentage rate of acute viral infection
among children with AEBA
Pathogen
Asthma
Control
p Value
Influenza virus type A
20
3
<0.0001
Influenza virus type B
0
0
NS
Parainfluenza virus type 1
6
2
NS
Parainfluenza virus type 2
0
0
NS
Parainfluenza virus type 3
2
1
NS
Adenovirus
18
1
<0.0001
Respiratory syncytial virus
10
0
<0.001
One or more of the above
14
2
<0.0001

16. Conclusions
1-Acute infection with either Chlamydia
pneumoniae or Mycoplasma pneumoniae has
an important role in acute exacerbations of
bronchial asthma among adults.
2-Acute infection with the 4 atypical pathogens
has no position in acute exacerbations of
bronchial asthma among Children.
3-Viral infections plays an important role in
AEBA in both adults and children.

17. Recommendation
• The therapeutic significance of the
findings of this study need to be
evaluated in future studies designed
specifically to address this issue.