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I removed the word "also" from the current last paragraph describing CSF, and added 2 paragraphs in C. pneumniae and asthma, The first paragraph describes some associations and clinical observations. The second paragraph describes some recent treatment tr
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''C. pneumoniae'' has been found in the cerebrospinal fluid of some patients diagnosed with multiple sclerosis.<ref name="pmid10401775">{{cite journal |author=Sriram S, Stratton CW, Yao S, ''et al.'' |title=Chlamydia pneumoniae infection of the central nervous system in multiple sclerosis |journal=Ann. Neurol. |volume=46 |issue=1 |pages=6–14 |year=1999 |pmid=10401775 |doi= 10.1002/1531-8249(199907)46:1<6::AID-ANA4>3.0.CO;2-M|accessdate=}}</ref>
''C. pneumoniae'' has been found in the cerebrospinal fluid of some patients diagnosed with multiple sclerosis.<ref name="pmid10401775">{{cite journal |author=Sriram S, Stratton CW, Yao S, ''et al.'' |title=Chlamydia pneumoniae infection of the central nervous system in multiple sclerosis |journal=Ann. Neurol. |volume=46 |issue=1 |pages=6–14 |year=1999 |pmid=10401775 |doi= 10.1002/1531-8249(199907)46:1<6::AID-ANA4>3.0.CO;2-M|accessdate=}}</ref>


Serological evidence for possible chronic C. pneumoniae infection was first associated with wheezing, asthmatic bronchitis and adult-onset asthma in 1991.<ref name="pmid2056624">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> Subsequent studies of bronchoalveolar lavage fluid from pediatric patients with severe chronic respiratory illnesses including asthma have demonstrated that over half had evidence of C. pneumoniae by direct organism identification.<ref name="pmid11737672">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref><ref name="pmid15735056">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> The only prospective study of new-onset adult asthma carried out in a primary care clinic diagnosed acute C. pneumoniae infection serologically in 5/5 patients with acute wheezing that became chronic and was later diagnosed as asthma, and in another patient who developed chronic bronchitis who had the organism cultured from his sputum 6 months after illness onset.<ref name="pmid9809498">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> These observations suggest that acute C. pneumniae infection is capable of causing protean manifestations of chronic respiratory illness, some of which is diagnosed as asthma.
Serological evidence for possible chronic C. pneumoniae infection was first associated with wheezing, asthmatic bronchitis and adult-onset asthma in 1991.<ref name="pmid2056624">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> Subsequent studies of bronchoalveolar lavage fluid from pediatric patients with severe chronic respiratory illnesses including asthma have demonstrated that over half had evidence of C. pneumoniae by direct organism identification.<ref name="pmid11737672">{{cite journal |author=Schmidt SM, Muller CE, Bruns R, ''et al.'' |title=Bronchial Chlamydia pneumoniae infection, markers of allergic inflammation and lung function in children |journal=Pediatr Allergy Immunol. |volume=12 |issue= |pages=257-265 |year=2001 |pmid=11737672}}</ref><ref name="pmid15735056">{{cite journal |author=Webley WC, Salva PS, Andrzejewski C, ''et al.'' |title=The bronchial lavage of pediatric patients with asthma contains infectious Chlamydia |journal=Am J Respir Crit Care Med. |volume=171 |issue= |pages=1083-1088 |year=2005 |pmid=15735056}}</ref> The only prospective study of new-onset adult asthma carried out in a primary care clinic diagnosed acute C. pneumoniae infection serologically in 5/5 patients with acute wheezing that became chronic and that was later diagnosed as asthma, and in another patient who developed new-onset chronic bronchitis who had the organism cultured from his sputum 6 months after illness onset.<ref name="pmid9809498">{{cite journal |author=Hahn DL, McDonald R |title=Can acute Chlamydia pneumoniae infection initiate chronic asthma? |journal=Ann Allergy Asthma Immunol. |volume=81 |issue= |pages=339-344 |year=1998 |pmid=9809498}}</ref> These observations suggest that acute C. pneumoniae infection is capable of causing protean manifestations of chronic respiratory illness, some of which is diagnosed as asthma.


That these associations are clinically relevant in the primary care setting is suggested by the results of two observational trials<ref name="pmid7561707">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref><ref name="pmid22545149">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> and two randomized controlled trials<ref name="pmid16871333">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref><ref name="pmid22773713">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> of azithromycin treatment for asthma. One of these RCTs<ref name="pmid22773713">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> and another macrolide trial<ref name="pmid9809498">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> suggest that the treatment effect may be greatest in patients with severe, refractory asthma. These clinical results correlate with epidemiological evidence that C. pneumoniae is positively associated with asthma severity<ref name="pmid9809498">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> and laboratory evidence that C. pneumoniae infection creates steroid-resistance.<ref name="pmid16393329">{{cite journal |author=Hahn DL, Dodge R, Golubjatnikov R |title=Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma |journal=JAMA. |volume=266 |issue= |pages=225-230 |year=1991 |pmid=2056624}}</ref> Currently available asthma guidelines do not address this evidence.
That these associations are clinically relevant in the primary care setting is suggested by the results of two observational trials<ref name="pmid7561707">{{cite journal |author=Hahn DL |title=Treatment of Chlamydia pneumoniae infection in adult asthma: a before-after trial |journal=J Fam Pract. |volume=41 |issue= |pages=345-351 |year=1995 |pmid=7561707}}</ref><ref name="pmid22545149">{{cite journal |author=Hahn DL, Schure A, Patel K, ''et al.'' |title=Chlamydia pneumoniae-specific IgE is prevalent in asthma and is associated with disease severity |journal=PLoS ONE. |volume=7 |issue= |pages=e35945 |year=2012 |pmid=22545149}}</ref> and two randomized controlled trials<ref name="pmid16871333">{{cite journal |author=Hahn DL, Plane MB, Mahdi OS, ''et al.'' |title=Secondary outcomes of a pilot randomized trial of azithromycin treatment for asthma |journal=PLoS Clin Trials. |volume=1 |issue= |pages=e11 |year=2006 |pmid=16871333}}</ref><ref name="pmid22773713">{{cite journal |author=Hahn DL, Grasmick M, Hetzel S, ''et al.'' |title=Azithromycin for bronchial asthma in adults: An effectiveness trial |journal=J Am Bd Fam Med. |volume=25 |issue= |pages=442-459 |year=2012 |pmid=22773713}}</ref> of azithromycin treatment for asthma. One of these RCTs<ref name="pmid22773713">{{cite journal |author=Hahn DL, Grasmick M, Hetzel S, ''et al.'' |title=Azithromycin for bronchial asthma in adults: An effectiveness trial |journal=J Am Bd Fam Med. |volume=25 |issue= |pages=442-459 |year=2012 |pmid=22773713}}</ref> and another macrolide trial<ref name="pmid17947611">{{cite journal |author=Simpson JL, Powell H, Boyle MJ, ''et al.'' |title=Clarithromycin targets neutrophilic airway inflammation in refractory asthma |journal=Am J Respir Crit Care Med. |volume=177 |issue= |pages=148-155 |year=2008 |pmid=17947611}}</ref> suggest that the treatment effect may be greatest in patients with severe, refractory asthma. These clinical results correlate with epidemiological evidence that C. pneumoniae is positively associated with asthma severity<ref name="pmid11874160">{{cite journal |author=von Hertzen L, Vasankari T, Liippo K, ''et al.'' |title=Chlamydia pneumoniae and severity of asthma |journal=Scand J Infect Dis. |volume=34 |issue= |pages=22-27 |year=2002 |pmid=11874160}}</ref> and laboratory evidence that C. pneumoniae infection creates steroid-resistance.<ref name="pmid16393329">{{cite journal |author=Cho YS, Kim TB, Lee TH, ''et al.'' |title=Chlamydia pneumoniae infection enhances cellular proliferation and reduces steroid responsiveness of human peripheral blood mononuclear cells via a tumor necrosis factor-alpha-dependent pathway |journal=Clinical & Experimental Allergy. |volume=35 |issue= |pages=1625-1631 |year=2005 |pmid=16393329}}</ref> Currently available asthma guidelines do not address this evidence.
== References ==
== References ==
{{reflist|2}}
{{reflist|2}}

Revision as of 23:29, 26 August 2012

Chlamydia pneumoniae
Scientific classification
Kingdom:
Bacteria
Phylum:
Chlamydiae
Order:
Chlamydiales
Family:
Chlamydiaceae
Genus:
Chlamydophila
Species:
C. pneumoniae

Chlamydophila pneumoniae is a species of Chlamydophila, an obligate intracellular bacterium[1] that infects humans and is a major cause of pneumonia. It was known as the Taiwan acute respiratory agent (TWAR) from the names of the two original isolates - Taiwan (TW-183) and an acute respiratory isolate designated AR-39.[2] Until recently, it was known as Chlamydia pneumoniae, and that name is used as an alternate in some sources.[3] In some cases, to avoid confusion, both names are given.[4]

C. pneumoniae has a complex life cycle and must infect another cell to reproduce; thus, it is classified as an obligate intracellular pathogen. The full genome sequence for C. pneumoniae was published in 1999. It also infects and causes disease in koalas, emerald tree boas (Corallus caninus), iguanas, chameleons, frogs, and turtles.

The first known case of infection with C. pneumoniae was a case of sinusitis in Taiwan. This atypical bacterium commonly causes pharyngitis, bronchitis and atypical pneumonia,[5] mainly in elderly and debilitated patients, but in healthy adults, also.[6]

Micrograph ofChlamydophila (Chlamydia) pneumoniae in an epithelial cell in acute bronchitis: 1 - infected epitheliocyte, 2 - uninfected epitheliocytes, 3 - chlamydial inclusion bodies in cell, 4 - cell nuclei


Life cycle and method of infection

Life cycle of Chlamydophila pneumoniae

Chlamydophila pneumoniae is a small bacterium (0.2 to 1 μm) that undergoes several transformations during its life cycle. It exists as an elementary body (EB) between hosts. The EB is not biologically active, but is resistant to environmental stresses and can survive outside a host for a limited time. The EB travels from an infected person to the lungs of an uninfected person in small droplets and is responsible for infection. Once in the lungs, the EB is taken up by cells in a pouch called an endosome by a process called phagocytosis. However, the EB is not destroyed by fusion with lysosomes, as is typical for phagocytosed material. Instead, it transforms into a reticulate body and begins to replicate within the endosome. The reticulate bodies must use some of the host's cellular metabolism to complete its replication. The reticulate bodies then convert back to elementary bodies and are released back into the lung, often after causing the death of the host cell. The EBs are thereafter able to infect new cells, either in the same organism or in a new host. Thus, the life cycle of C. pneumoniae is divided between the elementary body, which is able to infect new hosts but can not replicate, and the reticulate body, which replicates but is not able to cause new infection.

Diseases

C. pneumoniae is a common cause of pneumonia around the world; it is typically acquired by otherwise healthy people and is a form of community-acquired pneumonia. Because its treatment and diagnosis are different from historically recognized causes, such as Streptococcus pneumoniae, pneumonia caused by C. pneumoniae is categorized as an "atypical pneumonia" .[7].

In addition to pneumonia, C. pneumoniae less commonly causes several other illnesses. Among these are meningoencephalitis (infection and inflammation of the brain and meninges), arthritis, myocarditis (inflammation of the heart), and Guillain-Barré syndrome.[who?][citation needed]

Multiple studies have evaluated prior C. pneumoniae infection and a possible connection to lung cancer. One meta-analysis of serological data comparing prior C. pneumoniae infection in patients with and without lung cancer found results suggesting prior infection was associated with a slightly increased risk of developing lung cancer.[8]

In research into the association between C. pneumoniae infection and atherosclerosis and coronary artery disease, serological testing, direct pathologic analysis of plaques and in vitro testing suggest chronic infection with C. pneumoniae may be a risk factor for development of atherosclerotic plaques. C. pneumoniae infection increases adherence of macrophages to endothelial cells in vitro and aortas ex vivo.[9] However, the current data do not define how often C. pneumoniae is found in atherosclerotic or normal vascular tissue, nor does it allow for determining whether C. pneumoniae infection has a causative effect on atheroma formation or is merely an "innocent passenger" in these plaques. The largest trials that studied the use of antibiotics as a prevention for diseases associated with atherosclerosis, such as heart attacks and strokes, did not show any significant difference between antibiotics and placebo.[10]

C. pneumoniae has been found in the cerebrospinal fluid of some patients diagnosed with multiple sclerosis.[11]

Serological evidence for possible chronic C. pneumoniae infection was first associated with wheezing, asthmatic bronchitis and adult-onset asthma in 1991.[12] Subsequent studies of bronchoalveolar lavage fluid from pediatric patients with severe chronic respiratory illnesses including asthma have demonstrated that over half had evidence of C. pneumoniae by direct organism identification.[13][14] The only prospective study of new-onset adult asthma carried out in a primary care clinic diagnosed acute C. pneumoniae infection serologically in 5/5 patients with acute wheezing that became chronic and that was later diagnosed as asthma, and in another patient who developed new-onset chronic bronchitis who had the organism cultured from his sputum 6 months after illness onset.[15] These observations suggest that acute C. pneumoniae infection is capable of causing protean manifestations of chronic respiratory illness, some of which is diagnosed as asthma.

That these associations are clinically relevant in the primary care setting is suggested by the results of two observational trials[16][17] and two randomized controlled trials[18][19] of azithromycin treatment for asthma. One of these RCTs[19] and another macrolide trial[20] suggest that the treatment effect may be greatest in patients with severe, refractory asthma. These clinical results correlate with epidemiological evidence that C. pneumoniae is positively associated with asthma severity[21] and laboratory evidence that C. pneumoniae infection creates steroid-resistance.[22] Currently available asthma guidelines do not address this evidence.

References

  1. ^ Chlamydophila+pneumoniae at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
  2. ^ http://pathmicro.med.sc.edu/mayer/chlamyd.htm
  3. ^ "www.ncbi.nlm.nih.gov". Retrieved 2009-01-27.
  4. ^ Appelt DM, Roupas MR, Way DS; et al. (2008). "Inhibition of apoptosis in neuronal cells infected with Chlamydophila (Chlamydia) pneumoniae". BMC Neurosci. 9: 13. doi:10.1186/1471-2202-9-13. PMC 2266938. PMID 18218130. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link) CS1 maint: unflagged free DOI (link)
  5. ^ Lang, B. R., Chlamydia pneumonia as a differential diagnosis? Follow-up to a case report on progressive pneumonitis in an adolescent, Patient Care, Sept. 15, 1991
  6. ^ Little, Linda, Elusive pneumonia strain frustrates many clinicians, Medical Tribune, p. 6, September 19, 1991
  7. ^ Pignanelli S, Shurdhi A, Delucca F; et al. (2009). "Simultaneous use of direct and indirect diagnostic techniques in atypical respiratory infections from Chlamydophila pneumoniae and Mycoplasma pneumoniae". J Clin Lab Anal. 23 (4): 206–9. PMID 19623657. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  8. ^ Zhan P, Suo LJ, Qian Q; et al. (2011). "Chlamydia pneumoniae infection and lung cancer risk: A meta-analysis". Eur. J. Cancer. 47 (5): 742–7. doi:10.1016/j.ejca.2010.11.003. PMID 21194924. {{cite journal}}: Explicit use of et al. in: |author= (help); Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  9. ^ Takaoka N, Campbell LA, Lee A, Rosenfeld ME, Kuo CC (2008). "Chlamydia pneumoniae infection increases adherence of mouse macrophages to mouse endothelial cells in vitro and to aortas ex vivo". Infect Immun. 76 (2): 510–4. doi:10.1128/IAI.01267-07. PMID 18070891. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  10. ^ Mussa FF, Chai H, Wang X, Yao Q, Lumsden AB, Chen C (2006). "Chlamydia pneumoniae and vascular disease: an update". J. Vasc. Surg. 43 (6): 1301–7. doi:10.1016/j.jvs.2006.02.050. PMID 16765261. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  11. ^ Sriram S, Stratton CW, Yao S; et al. (1999). "Chlamydia pneumoniae infection of the central nervous system in multiple sclerosis". Ann. Neurol. 46 (1): 6–14. doi:10.1002/1531-8249(199907)46:1<6::AID-ANA4>3.0.CO;2-M. PMID 10401775. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  12. ^ Hahn DL, Dodge R, Golubjatnikov R (1991). "Association of Chlamydia pneumoniae (strain TWAR) infection with wheezing, asthmatic bronchitis and adult-onset asthma". JAMA. 266: 225–230. PMID 2056624.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  13. ^ Schmidt SM, Muller CE, Bruns R; et al. (2001). "Bronchial Chlamydia pneumoniae infection, markers of allergic inflammation and lung function in children". Pediatr Allergy Immunol. 12: 257–265. PMID 11737672. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  14. ^ Webley WC, Salva PS, Andrzejewski C; et al. (2005). "The bronchial lavage of pediatric patients with asthma contains infectious Chlamydia". Am J Respir Crit Care Med. 171: 1083–1088. PMID 15735056. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  15. ^ Hahn DL, McDonald R (1998). "Can acute Chlamydia pneumoniae infection initiate chronic asthma?". Ann Allergy Asthma Immunol. 81: 339–344. PMID 9809498.
  16. ^ Hahn DL (1995). "Treatment of Chlamydia pneumoniae infection in adult asthma: a before-after trial". J Fam Pract. 41: 345–351. PMID 7561707.
  17. ^ Hahn DL, Schure A, Patel K; et al. (2012). "Chlamydia pneumoniae-specific IgE is prevalent in asthma and is associated with disease severity". PLoS ONE. 7: e35945. PMID 22545149. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  18. ^ Hahn DL, Plane MB, Mahdi OS; et al. (2006). "Secondary outcomes of a pilot randomized trial of azithromycin treatment for asthma". PLoS Clin Trials. 1: e11. PMID 16871333. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  19. ^ a b Hahn DL, Grasmick M, Hetzel S; et al. (2012). "Azithromycin for bronchial asthma in adults: An effectiveness trial". J Am Bd Fam Med. 25: 442–459. PMID 22773713. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  20. ^ Simpson JL, Powell H, Boyle MJ; et al. (2008). "Clarithromycin targets neutrophilic airway inflammation in refractory asthma". Am J Respir Crit Care Med. 177: 148–155. PMID 17947611. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  21. ^ von Hertzen L, Vasankari T, Liippo K; et al. (2002). "Chlamydia pneumoniae and severity of asthma". Scand J Infect Dis. 34: 22–27. PMID 11874160. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  22. ^ Cho YS, Kim TB, Lee TH; et al. (2005). "Chlamydia pneumoniae infection enhances cellular proliferation and reduces steroid responsiveness of human peripheral blood mononuclear cells via a tumor necrosis factor-alpha-dependent pathway". Clinical & Experimental Allergy. 35: 1625–1631. PMID 16393329. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=Chlamydia_pneumoniae&oldid=509330873"