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Atypical organisms affecting the respiratory tract and their sequelae – a series of case studies

Van Woerden, Hugo 2012. Atypical organisms affecting the respiratory tract and their sequelae – a series of case studies. PhD Thesis, Cardiff University.
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The respiratory tract is exposed to a wide range of environmental constituents including potentially infective agents. This thesis presents two series of papers concerning two atypical organisms and their sequelae or potential sequelae – Coxiella burnetii, which causes Q fever, and flagellated protozoa, which is associated with respiratory symptoms and asthma. The first series of papers examine a Q fever outbreak and its sequelae. They describe one of the largest Q fever outbreaks in the UK and demonstrate the benefit of facsimile cascade in supporting case searching in such an outbreak. Chronic fatigue (Chalder Fatigue scores) and depression (PHQ-9 scores) were raised in post Q fever patients six years later (p<0.05 in both cases). Concordance regarding serological status across three international reference laboratories was as low as 35%, indicating a major problem with international standardisation in this area. Unpublished supplementary clinical and serological findings are also presented to inform future outbreak investigation. The second series of papers examine the role of flagellated protozoa in respiratory disease. Flagellated protozoa were shown to be present in a case series of inpatients. In a subsequent community-based case control study, protozoa were present in 67% (20/30) of induced sputum samples taken from asthmatics and 31% (4/13) of samples from non-atopic controls (p=0.046). In another study of inpatients, 67% of those who were on oral steroids had protozoa in their sputum, compared to 35% of those not on oral steroids. In this study, 45% of smokers/ex-smokers had protozoa in their sputum compared to 30% of non-smokers. Unpublished data using molecular techniques to identify eukaryotes in sputum is also presented. The findings provide a basis for a RCT of antibiotics in patients with post Q fever chronic fatigue and a trial of anti-protozoal agents to eradicate flagellated protozoa in patients with asthma.

Item Type: Thesis (PhD)
Status: Unpublished
Schools: Medicine
Subjects: R Medicine > R Medicine (General)
Date of First Compliant Deposit: 30 March 2016
Last Modified: 19 Mar 2016 23:07

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