Value of 18F-FDG PET/CT in diagnosing chronic Q fever in patients with central vascular disease.

BACKGROUND: The aim of this study is to describe the value of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) in diagnosing chronic Q fever in patients with central vascular disease and the added value of 18F-FDG PET/CT in the diagnostic combination strategy as described in the Dutch consensus guideline for diagnosing chronic Q fever. METHODS: 18F-FDG PET/CT was performed in patients with an abdominal aortic aneurysm or aorto-iliac reconstruction and chronic Q fever, diagnosed by serology and positive PCR for Coxiella burnetii DNA in blood and/or tissue (PCR-positive study group). Patients with an abdominal aortic aneurysm or aorto-iliac reconstruction without clinical and serological findings indicating Q fever infection served as a control group. Patients with a serological profile of chronic Q fever and a negative PCR in blood were included in additional analyses (PCR-negative study group). RESULTS: Thirteen patients were evaluated in the PCR-positive study group and 22 patients in the control group. 18F-FDG PET/CT indicated vascular infection in 6/13 patients in the PCR-positive study group and 2/22 patients in the control group. 18F-FDG PET/CT demonstrated a sensitivity of 46% (95% CI: 23-71%), specificity of 91% (95% CI: 71-99%), positive predictive value of 75% (95% CI:41-93%) and negative predictive value of 74% (95% CI: 55-87%). In the PCR-negative study group, 18F-FDG PET/CT was positive in 10/20 patients (50%). CONCLUSION: The combination of 18F-FDG PET/CT, as an imaging tool for identifying a focus of infection, and Q fever serology is a valid diagnostic strategy for diagnosing chronic Q fever in patients with central vascular disease.

Vascular chronic Q fever: quality of life.

The aim of this study was to evaluate the quality of life in patients with vascular chronic Q fever at time of diagnosis and during follow-up. Based upon the SF-36 questionnaire, the mean physical and mental health of each patient were assessed at 3-month intervals for up to 18 months. A total of 26 patients were included in the study. At time of diagnosis, the mean physical health and mental health score was 50·6 [95% confidence interval (CI) 46·7-54·4] and 44·6 (95% CI 41·6-47·5), respectively. During treatment, the mean physical health score declined significantly by 1·7 points each 3 months (P < 0·001) to 40·8 (95% CI 34·4-45·1). The mean mental health score significantly and steadily increased towards 51·2 (95% CI 46·9-54·3) during follow-up (P = 0·026). A total of 23% of patients were cured after 18 months of follow-up. In conclusion, quality of life at time of diagnosis for patients with vascular chronic Q fever is lower compared to a similar group of patients, matched for age and gender, with an aortic abdominal aneurysmal disease, and physical health decreases further after starting treatment. Considering the low percentage of cure, the current treatment of vascular chronic Q fever patients may require a separate strategy from that of endocarditis in order to increase survival.

Serological follow-up in patients with aorto-iliac disease and evidence of Q fever infection.

The aim of this study was to provide data on the risk of developing chronic Q fever in patients with aorto-iliac disease and evidence of previous Q fever infection. Patients with an aortic and/or iliac aneurysm or aorto-iliac reconstruction (aorto-iliac disease) and evidence of previous Q fever infection were included. The presence of phase I and II Coxiella burnetii IgG antibodies was assessed periodically using immunofluorescence assay. A total of 111 patients with aorto-iliac disease were divided into three groups, based upon the serological profile [mean follow-up: 16 ± 9 months (mean ± standard deviation)]. Group 1 consisted of 30 patients with a serological trace of C. burnetii infection (negative IgG phase I, IgG phase II titer of 1:32). Of these, 36.7% converted to serological profile matching past resolved Q fever. Group 2 included 49 patients with negative IgG phase I titer and IgG phase II titer ≥1:64. No patients developed chronic Q fever, but 14.3% converted to a positive IgG phase I titer. Group 3 consisted of 32 patients with positive IgG phase I and positive IgG phase II titers, of which 9.4% developed chronic Q fever (significantly different from group 2, p = 0.039). The IgG phase I titer increased in 28.1% of patients (from 1:64 to 1:4,096). The risk of developing chronic Q fever in patients with aorto-iliac disease and previous Q fever infection with a positive IgG phase I titer was 9.4%. The IgG phase I titer increases or becomes positive in a substantial number of patients. A standardized serological follow-up is proposed.

Screening for Coxiella burnetii seroprevalence in chronic Q fever high-risk groups reveals the magnitude of the Dutch Q fever outbreak.

The Netherlands experienced an unprecedented outbreak of Q fever between 2007 and 2010. The Jeroen Bosch Hospital (JBH) in 's-Hertogenbosch is located in the centre of the epidemic area. Based on Q fever screening programmes, seroprevalence of IgG phase II antibodies to Coxiella burnetii in the JBH catchment area was 10·7% [785 tested, 84 seropositive, 95% confidence interval (CI) 8·5-12·9]. Seroprevalence appeared not to be influenced by age, gender or area of residence. Extrapolating these data, an estimated 40 600 persons (95% CI 32 200-48 900) in the JBH catchment area have been infected by C. burnetii and are, therefore, potentially at risk for chronic Q fever. This figure by far exceeds the nationwide number of notified symptomatic acute Q fever patients and illustrates the magnitude of the Dutch Q fever outbreak. Clinicians in epidemic Q fever areas should be alert for chronic Q fever, even if no acute Q fever is reported.

Timing of cholecystectomy after mild biliary pancreatitis.

BACKGROUND: The aim of the study was to evaluate recurrent biliary events as a consequence of delay in cholecystectomy following mild biliary pancreatitis. METHODS: Between 2004 and 2007, patients with acute pancreatitis were registered prospectively in 15 Dutch hospitals. Patients with mild biliary pancreatitis were candidates for cholecystectomy. Recurrent biliary events requiring admission before and after cholecystectomy, and after endoscopic sphincterotomy (ES), were evaluated. RESULTS: Of 308 patients with mild biliary pancreatitis, 267 were candidates for cholecystectomy. Eighteen patients underwent cholecystectomy during the initial admission, leaving 249 potential candidates for cholecystectomy after discharge. Cholecystectomy was performed after a median of 6 weeks in 188 patients (75·5 per cent). Before cholecystectomy, 34 patients (13·7 per cent) were readmitted for biliary events, including 24 with recurrent biliary pancreatitis. ES was performed in 108 patients during the initial admission. Eight (7·4 per cent) of these patients suffered from biliary events after ES and before cholecystectomy, compared with 26 (18·4 per cent) of 141 patients who did not have ES (risk ratio 0·51, 95 per cent confidence interval 0·27 to 0·94; P = 0·015). Following cholecystectomy, eight (3·9 per cent) of 206 patients developed biliary events after a median of 31 weeks. Only 142 (53·2 per cent) of 267 patients were treated in accordance with the Dutch guideline, which recommends cholecystectomy or ES during the index admission or within 3 weeks thereafter. CONCLUSION: A delay in cholecystectomy after mild biliary pancreatitis carries a substantial risk of recurrent biliary events. ES reduces the risk of recurrent pancreatitis but not of other biliary events.