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Featured researches published by Stephan P. Keijmel.


BMC Infectious Diseases | 2013

Localizing chronic Q fever: a challenging query

Dennis G. Barten; Corine E. Delsing; Stephan P. Keijmel; Tom Sprong; Janneke Timmermans; Wim J.G. Oyen; Marrigje H. Nabuurs-Franssen; Chantal P. Bleeker-Rovers

BackgroundChronic Q fever usually presents as endocarditis or endovascular infection. We investigated whether 18F-FDG PET/CT and echocardiography were able to detect the localization of infection. Also, the utility of the modified Duke criteria was assessed.MethodsFifty-two patients, who had an IgG titre of ≥ 1024 against C. burnetii phase I ≥ 3 months after primary infection or a positive PCR ≥ 1 month after primary infection, were retrospectively included. Data on serology, the results of all imaging studies, possible risk factors for developing proven chronic Q fever and clinical outcome were recorded.ResultsAccording to the Dutch consensus on Q fever diagnostics, 18 patients had proven chronic Q fever, 14 probable chronic Q fever, and 20 possible chronic Q fever. Of the patients with proven chronic Q fever, 22% were diagnosed with endocarditis, 17% with an infected vascular prosthesis, and 39% with a mycotic aneurysm. 56% of patients with proven chronic Q fever did not recall an episode of acute Q fever. Ten out of 13 18F-FDG PET/CT-scans in patients with proven chronic Q fever localized the infection. TTE and TEE were helpful in only 6% and 50% of patients, respectively.ConclusionsIf chronic Q fever is diagnosed, 18F-FDG PET/CT is a helpful imaging technique for localization of vascular infections due to chronic Q fever. Patients with proven chronic Q fever were diagnosed significantly more often with mycotic aneurysms than in previous case series. Definite endocarditis due to chronic Q fever was less frequently diagnosed in the current study. Chronic Q fever often occurs in patients without a known episode of acute Q fever, so clinical suspicion should remain high, especially in endemic regions.


BMC Infectious Diseases | 2013

The Qure study: Q fever fatigue syndrome – response to treatment; a randomized placebo-controlled trial

Stephan P. Keijmel; Corine E. Delsing; Tom Sprong; Gijs Bleijenberg; Jos W. M. van der Meer; Hans Knoop; Chantal P. Bleeker-Rovers

BackgroundQ fever is a zoonosis that is present in many countries. Q fever fatigue syndrome (QFS) is one of the most frequent sequelae after an acute Q fever infection. QFS is characterized by persistent fatigue following an acute Q fever infection, leading to substantial morbidity and a high socio-economic burden. The occurrence of QFS is well-documented, and has been described in many countries over the past decades. However, a treatment with proven efficacy is not available. Only a few uncontrolled studies have tested the efficacy of treatment with antibiotics on QFS. These studies suggest a positive effect of long-term treatment with a tetracycline on performance state; however, no randomized controlled trials have been performed. Cognitive behavioral therapy (CBT) has been proven to be an effective treatment modality for chronic fatigue in other diseases, but has not yet been tested in QFS. Therefore, we designed a trial to assess the efficacy of long-term treatment with the tetracycline doxycycline and CBT in patients with QFS.Methods/designA randomized placebo-controlled trial will be conducted. One-hundred-eighty adult patients diagnosed with QFS will be recruited and randomized between one of three groups: CBT, long-term doxycycline or placebo. First, participants will be randomized between CBT and medication (ratio 1:2). A second double-blinded randomization between doxycycline and placebo (ratio 1:1) will be performed in the medication condition. Each group will be treated for six months. Outcome measures will be assessed at baseline and post intervention. The primary outcome measure is fatigue severity. Secondary outcome measures are functional impairment, level of psychological distress, and Coxiella burnetii PCR and serology.DiscussionThe Qure study is the first randomized placebo-controlled trial, which evaluates the efficacy of long-term doxycycline and of cognitive behavioral therapy in patients with QFS. The results of this study will provide knowledge about evidence-based treatment options for adult patients with QFS.Trial registrationClinicalTrials.gov: http://NCT01318356, and Netherlands Trial Register: NTR2797


Emerging Infectious Diseases | 2015

Differentiation of Acute Q Fever from Other Infections in Patients Presenting to Hospitals, the Netherlands(1)

Stephan P. Keijmel; Elmer Krijger; Corine E. Delsing; Tom Sprong; Marrigje H. Nabuurs-Franssen; Chantal P. Bleeker-Rovers

Distinguishing acute Q fever from respiratory infections, fever, or hepatitis requires serologic testing or PCR.


Clinical Infectious Diseases | 2017

Effectiveness of Long-term Doxycycline Treatment and Cognitive-Behavioral Therapy on Fatigue Severity in Patients with Q Fever Fatigue Syndrome (Qure Study): A Randomized Controlled Trial

Stephan P. Keijmel; Corine E. Delsing; Gijs Bleijenberg; Jos W. M. van der Meer; Rogier Donders; Monique Leclercq; Linda M. Kampschreur; Michel van den Berg; Tom Sprong; Marrigje H. Nabuurs-Franssen; Hans Knoop; Chantal P. Bleeker-Rovers

Background Approximately 20% of patients with acute Q fever will develop chronic fatigue, referred to as Q fever fatigue syndrome (QFS). The objective of this randomized controlled clinical trial was to assess the efficacy of either long-term treatment with doxycycline or cognitive-behavioral therapy (CBT) in reducing fatigue severity in patients with QFS. Methods Adult patients were included who met the QFS criteria according to the Dutch guideline: a new onset of severe fatigue lasting ≥6 months with significant disabilities, related to an acute Q fever infection, without other somatic or psychiatric comorbidity explaining the fatigue. Using block randomization, patients were randomized between oral study medication and CBT (2:1) for 24 weeks. Second, a double-blind randomization between doxycycline (200 mg/day, once daily) and placebo was performed in the medication group. Primary outcome was fatigue severity at end of treatment (EOT; week 26), assessed with the Checklist Individual Strength subscale Fatigue Severity. Results Of 155 patients randomized, 154 were included in the intention-to-treat analysis (doxycycline, 52; placebo, 52; CBT, 50). At EOT, fatigue severity was similar between doxycycline (40.8 [95% confidence interval {CI}, 37.3-44.3]) and placebo (37.8 [95% CI, 34.3-41.2]; difference, doxycycline vs placebo, -3.0 [97.5% CI, -8.7 to 2.6]; P = .45). Fatigue severity was significantly lower after CBT (31.6 [95% CI, 28.0-35.1]) than after placebo (difference, CBT vs placebo, 6.2 [97.5% CI, .5-11.9]; P = .03). Conclusions CBT is effective in reducing fatigue severity in QFS patients. Long-term treatment with doxycycline does not reduce fatigue severity in QFS patients compared to placebo. Clinical Trials Registration NCT01318356.


PLOS ONE | 2016

Fatigue following Acute Q-Fever: A Systematic Literature Review

Gabriëlla Morroy; Stephan P. Keijmel; Corine E. Delsing; Gijs Bleijenberg; Miranda W. Langendam; Aura Timen; Chantal P. Bleeker-Rovers

Background Long-term fatigue with detrimental effects on daily functioning often occurs following acute Q-fever. Following the 2007–2010 Q-fever outbreak in the Netherlands with over 4000 notified cases, the emphasis on long-term consequences of Q-fever increased. The aim of this study was to provide an overview of all relevant available literature, and to identify knowledge gaps regarding the definition, diagnosis, background, description, aetiology, prevention, therapy, and prognosis, of fatigue following acute Q-fever. Design A systematic review was conducted through searching Pubmed, Embase, and PsycInfo for relevant literature up to 26th May 2015. References of included articles were hand searched for additional documents, and included articles were quality assessed. Results Fifty-seven articles were included and four documents classified as grey literature. The quality of most studies was low. The studies suggest that although most patients recover from fatigue within 6–12 months after acute Q-fever, approximately 20% remain chronically fatigued. Several names are used indicating fatigue following acute Q-fever, of which Q-fever fatigue syndrome (QFS) is most customary. Although QFS is described to occur frequently in many countries, a uniform definition is lacking. The studies report major health and work-related consequences, and is frequently accompanied by nonspecific complaints. There is no consensus with regard to aetiology, prevention, treatment, and prognosis. Conclusions Long-term fatigue following acute Q-fever, generally referred to as QFS, has major health-related consequences. However, information on aetiology, prevention, treatment, and prognosis of QFS is underrepresented in the international literature. In order to facilitate comparison of findings, and as platform for future studies, a uniform definition and diagnostic work-up and uniform measurement tools for QFS are proposed.


Journal of Psychosomatic Research | 2015

A comparison of patients with Q fever fatigue syndrome and patients with chronic fatigue syndrome with a focus on inflammatory markers and possible fatigue perpetuating cognitions and behaviour

Stephan P. Keijmel; Johanna Saxe; Jos W. M. van der Meer; Stephanie Nikolaus; Mihai G. Netea; Gijs Bleijenberg; Chantal P. Bleeker-Rovers; Hans Knoop

OBJECTIVE Comparison of Q fever fatigue syndrome (QFS) and chronic fatigue syndrome (CFS) patients, with a focus on markers of inflammation and fatigue-related cognitive-behavioural variables. METHODS Data from two independent prospective studies on QFS (n=117) and CFS (n=173), respectively, were pooled and analyzed. RESULTS QFS patients were less often female, had a higher BMI, and had less often received treatment for depression before the onset of symptoms. After controlling for symptom duration and correcting for differences in diagnostic criteria for QFS and CFS with respect to the level of impairment and the presence of additional symptoms, differences in the proportion of females and BMI remained significant. After correction, QFS patients were also significantly older. In all analyses QFS patients were as fatigued and distressed as CFS patients, but reported less additional symptoms. QFS patients had stronger somatic attributions, and higher levels of physical activity. No differences were found with regard to inflammatory markers and in other fatigue-related cognitive-behavioural variables. The relationship between cognitive-behavioural variables and fatigue, previously established in CFS, could not be confirmed in QFS patients with the exception of the negative relationship between physical activity and fatigue. CONCLUSION Differences and similarities between QFS and CFS patients were found. Although the relationship between perpetuating factors and fatigue previously established in CFS could not be confirmed in QFS patients, the considerable overlap in fatigue-related cognitive-behavioural variables and the relationship found between physical activity and fatigue may suggest that behavioural interventions could reduce fatigue severity in QFS patients.


Journal of Infection | 2016

Altered interferon-γ response in patients with Q-fever fatigue syndrome.

Stephan P. Keijmel; Ruud P. H. Raijmakers; Chantal P. Bleeker-Rovers; Jos W. M. van der Meer; Mihai G. Netea; Teske Schoffelen; Marcel van Deuren

OBJECTIVES Whether immunological mechanisms underlie Q-fever fatigue syndrome (QFS) remains unclear. For acute Q-fever, the antigen-specific interferon-γ (IFNγ) response may be a useful tool for diagnosis, and the IFNγ/interleukin(IL)-2 production ratio may be a marker for chronic Q-fever and treatment monitoring. Here we explored the specific IFNγ production and IFNγ/IL-2 ratio in QFS patients. METHODS IFNγ and IL-2 production were tested in ex-vivo stimulated whole blood of QFS patients (n = 20), and compared to those previously determined in seropositive controls (n = 135), and chronic Q-fever patients (n = 28). Also, the correlation between patient characteristics and IFNγ, IL-2, and IFNγ/IL-2 ratio was determined. RESULTS QFS patients were younger (p < 0.001), but gender distribution was similar to seropositive controls and chronic Q-fever patients. Coxiella burnetii Nine Mile stimulation revealed a higher IFNγ production in QFS (median 319.5 pg/ml) than in seropositive controls (120 pg/ml, p < 0.01), but comparable to chronic Q-fever (2846 pg/ml). The IFNγ/IL-2 ratio was similar to that in seropositive controls, but lower than in chronic Q-fever patients (p < 0.01). Symptom duration was positively correlated with IL-2 production, and negatively correlated with the IFNγ/IL-2 ratio. CONCLUSIONS These results point to an altered cell-mediated immunity in QFS, and suggest a different immune response than in chronic Q-fever.


Infection | 2016

A fatal case of disseminated chronic Q fever: a case report and brief review of the literature

Stephan P. Keijmel; Ruud P. H. Raijmakers; Teske Schoffelen; Maria Carolina Wilhelmina Salet; Chantal P. Bleeker-Rovers

BackgroundChronic Q fever is a rare infection, which mainly manifests as endocarditis, infection of vascular prostheses or aortic aneurysms. We present the case of a 74-year-old immunocompromised man with a haematologically disseminated Coxiella burnetii infection, which has never been reported before.Case report He was diagnosed with a chronic Q fever infection of an aneurysm with an endovascular prosthesis in 2015, but he died despite optimal treatment. Autopsy revealed a disseminated C. burnetii infection, confirmed by a positive PCR on samples from several organs. Retrospectively, he already had complaints and signs of inflammation since 2012, for which he had already been admitted in February 2014. At that time, Q fever diagnostics using PCR, complement fixation assay, and enzyme-linked immunosorbent assay on serum were all negative. In retrospect however, retesting available samples from February 2014 using immunofluorescence assay (IFA) already revealed serology compatible with chronic Q fever.Conclusion Clinicians should be aware of this silent killer, especially in case of risk factors, and perform an appropriate diagnostic work-up for Q fever including IFA serology and PCR.


European Journal of Internal Medicine | 2018

Autoimmunity and B-cell dyscrasia in acute and chronic Q fever: A review of the literature

Anne F.M. Jansen; Ruud P. H. Raijmakers; Stephan P. Keijmel; Renate G. van der Molen; Gerald Vervoort; Jos W. M. van der Meer; Marcel van Deuren; Chantal P. Bleeker-Rovers

Q fever infection can lead to chronic Q fever, a potentially lethal disease occurring in 1-5% of patients infected with Coxiella burnetii, characterized by the persistence of this intracellular bacterium. It usually presents as endocarditis, infected vascular aneurysms, or infected vascular prostheses. This systematic review of the literature discusses the various autoimmune syndromes and B-cell dyscrasias in acute and chronic Q fever patients, that may interfere with or impede recognition and diagnosis of Q fever. Reportedly, high concentrations of anti-cardiolipin antibodies may be found in acute Q fever patients, while specifically cardiac muscle antibodies have been reported during chronic Q fever. Systemic lupus erythematosus and antiphospholipid syndrome are the most frequently reported autoimmune syndromes, followed by neuromuscular disorders and vasculitis. B-cell dyscrasia, mostly cryoglobulinaemia, is predominantly described in chronic Q fever patients with endocarditis. We conclude that immunological (epi)phenomena are not rare during Q fever and may obscure the infectious etiology of the disease.


Netherlands Journal of Medicine | 2015

Cutaneous hyperpigmentation induced by doxycycline: a case series

Stephan P. Keijmel; M.E.E. van Kasteren; W.A.M. Blokx; J.W.M. van der Meer; M.M. van Rossum; Chantal P. Bleeker-Rovers

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Corine E. Delsing

Radboud University Nijmegen Medical Centre

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Gijs Bleijenberg

Radboud University Nijmegen

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Hans Knoop

University of Amsterdam

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Tom Sprong

Radboud University Nijmegen

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Gabriëlla Morroy

Radboud University Nijmegen Medical Centre

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Mihai G. Netea

Radboud University Nijmegen

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