A randomised controlled trial testing the efficacy of Fit after COVID, a cognitive behavioural therapy targeting severe post-infectious fatigue following COVID-19 (ReCOVer): study protocol

BACKGROUND

Coronavirus disease 2019 (COVID-19) results in debilitating long-term symptoms, often referred to as Post-Acute Sequelae of SARS-CoV-2 Infection (PASC), in a substantial subgroup of patients. One of the most prevalent symptoms following COVID-19 is severe fatigue. Prompt delivery of cognitive behavioural therapy (CBT), an evidence-based treatment that has shown benefit in reducing severe fatigue in other conditions, may reduce post-COVID-19 fatigue. Based on an existing CBT protocol, a blended intervention of 17 weeks, Fit after COVID, was developed to treat severe fatigue after the acute phase of infection with SARS-CoV-2.

METHOD

The ReCOVer study is a multicentre 2-arm randomised controlled trial (RCT) to test the efficacy of Fit after COVID on severe post-infectious fatigue. Participants are eligible if they report severe fatigue 3 up to and including 12 months following COVID-19. One hundred and fourteen participants will be randomised to either Fit after COVID or care as usual (ratio 1:1). The primary outcome, the fatigue severity subscale of the Checklist Individual Strength (CIS-fatigue), is assessed in both groups before randomisation (T0), directly post CBT or following care as usual (T1), and at follow-up 6 months after the second assessment (T2). In addition, a long-term follow-up (T3), 12 months after the second assessment, is performed in the CBT group only. The primary objective is to investigate whether CBT will lead to a significantly lower mean fatigue severity score measured with the CIS-fatigue across the first two follow-up assessments (T1 and T2) as compared to care as usual. Secondary objectives are to determine the proportion of participants no longer being severely fatigued (operationalised in different ways) at T1 and T2 and to investigate changes in physical and social functioning, in the number and severity of somatic symptoms and in problems concentrating across T1 and T2.

DISCUSSION

This is the first trial testing a cognitive behavioural intervention targeting severe fatigue after COVID-19. If Fit after COVID is effective in reducing fatigue severity following COVID-19, this intervention could contribute to alleviating the long-term health consequences of COVID-19 by relieving one of its most prevalent and distressing long-term symptoms.

TRIAL REGISTRATION

Netherlands Trial Register NL8947 . Registered on 14 October 2020.

Impact of Q-fever fatigue syndrome on patients' work status

Background

Chronic illnesses can increase the risk of unemployment, but evidence on the specific impact of Q-fever fatigue syndrome (QFS) on work is lacking.

Aims

The aim of this study was to describe and quantify the impact of QFS on work.

Methods

Changes in work status from 1 year prior to 4 years after acute Q-fever infection of QFS patients were retrospectively collected with a self-report questionnaire measuring employment status and hours of paid work per week. In addition, information on work ability, job satisfaction and need for recovery after work was collected in 2016. Data were compared to participants from the general population.

Results

The proportion of employed QFS patients from 1 year prior to 4 years after acute infection decreased from 78 to 41%, while remaining relatively constant in the general population (82 to 78%). Working QFS patients showed a decrease in mean hours of paid work from 35 to 22 h per week, which is significantly steeper compared to the general population (31–28 h per week) (P < 0.001). QFS patients showed a significantly lower work ability (P < 0.001), lower job satisfaction (P = 0.006) and greater need for recovery (P < 0.001) compared to the general population.

Conclusions

The number of QFS patients with paid work decreased over the years, while patients who continue to work experience lower work ability, job satisfaction and increased need for recovery. Occupational physicians should be aware of the occurrence and severity of the impact of QFS on work, even after many years.

Single nucleotide polymorphism (SNP) rs3751143 in P2RX7 is associated with therapy failure in chronic Q fever while rs7125062 in MMP1 is associated with fewer complications

OBJECTIVES

Chronic Q fever is a persistent infection with the intracellular bacterium Coxiella burnetii. Development of chronic Q fever is associated with single nucleotide polymorphisms (SNPs) in genes encoding for pattern recognition receptors, for phagolysosomal pathway components and for matrix metalloproteinases (MMPs). We evaluated the association of SNPs in these innate-immunity and MMP genes with clinical outcomes.

METHODS

SNPs were selected from previous association studies and analysed in a cohort of patients with chronic Q fever. The primary outcome was all-cause mortality; secondary outcomes were therapy failure and chronic Q fever-related complications. Subdistribution hazard ratios (SHR) were calculated.

RESULTS

Nineteen SNPs were analysed in 134 patients with proven and 29 with probable chronic Q fever. In multivariable analysis, none of the selected SNPs was associated with all-cause mortality. However, SNP rs3751143 located in P2RX7 appeared to be associated with therapy failure (SHR 2.42; 95% confidence interval, 1.16-5.05; p 0.02), which is in line with other reports, showing that a loss of function of the P2X7 receptor leads to inefficient killing of intracellular organisms. In addition, SNP rs7125062 located in MMP1, involved in the cleavage of extracellular matrix, was associated with fewer chronic Q fever-related complications such as acute aneurysms (SHR 0.49; 95% confidence interval, 0.29-0.83; p 0.008).

CONCLUSIONS

A polymorphism in P2RX7, known to lead to loss of function of the receptor and inefficient killing of intracellular organisms, and a polymorphism in MMP1 were respectively associated with more therapy failures and fewer complications such as acute aneurysms in patients with chronic Q fever.

Surveillance-embedded genomic outbreak resolution of methicillin-susceptible Staphylococcus aureus in a neonatal intensive care unit

We observed an increase in methicillin-susceptible Staphylococcus aureus (MSSA) infections at a Dutch neonatal intensive care unit. Weekly neonatal MSSA carriage surveillance and cross-sectional screenings of health care workers (HCWs) were available for outbreak tracing. Traditional clustering of MSSA isolates by spa typing and Multiple-Locus Variable number tandem repeat Analysis (MLVA) suggested that nosocomial transmission had contributed to the infections. We investigated whether whole-genome sequencing (WGS) of MSSA surveillance would provide additional evidence for transmission. MSSA isolates from neonatal infections, carriage surveillance, and HCWs were subjected to WGS and bioinformatic analysis for identification and localization of high-quality single nucleotide polymorphisms, and in-depth analysis of subsets of isolates. By measuring the genetic diversity in background surveillance, we defined transmission-level relatedness and identified isolates that had been unjustly assigned to clusters based on MLVA, while spa typing was concordant but of insufficient resolution. Detailing particular subsets of isolates provided evidence that HCWs were involved in multiple outbreaks, yet it alleviated concerns about one particular HCW. The improved resolution and accuracy of genomic outbreak analyses substantially altered the view on outbreaks, along with apposite measures. Therefore, inclusion of the circulating background population has the potential to overcome current issues in genomic outbreak inference.

[Revision of guideline on Q fever fatigue syndrome (QFS)]

In 2012 the multidisciplinary guideline Q fever fatigue syndrome was developed for the Netherlands. The availability of new research data and developments and experiences from daily clinical practice made it necessary to revise this guideline. The multidisciplinary working group that has revised the guideline is composed of representatives from all medical professions involved in the care of patients with QFS and representatives of the patients' association. The revised guideline incorporates a number of changes, including refinement of the QFS diagnostic criteria and updates regarding advice on support and reintegration.

The effect of measuring serum doxycycline concentrations on clinical outcomes during treatment of chronic Q fever

Background

First choice treatment for chronic Q fever is doxycycline plus hydroxychloroquine. Serum doxycycline concentration (SDC) >5 μg/mL has been associated with a favourable serological response, but the effect on clinical outcomes is unknown.

Objectives

To assess the effect of measuring SDC during treatment of chronic Q fever on clinical outcomes.

Methods

We performed a retrospective cohort study, to assess the effect of measuring SDC on clinical outcomes in patients treated with doxycycline and hydroxychloroquine for chronic Q fever. Primary outcome was the first disease-related event (new complication or chronic Q fever-related mortality); secondary outcomes were all-cause mortality and PCR-positivity. Multivariable analysis was performed with a Cox proportional hazards model, with shared-frailty terms for different hospitals included.

Results

We included 201 patients (mean age 68 years, 83% male): in 167 patients (83%) SDC was measured, 34 patients (17%) were treated without SDC measurement. First SDC was >5 μg/mL in 106 patients (63%), all with 200 mg doxycycline daily. In patients with SDC measured, dosage was adjusted in 41% (n = 68), concerning an increase in 64 patients. Mean SDC was 4.1 μg/mL before dosage increase, and 5.9 μg/mL afterwards. SDC measurement was associated with a lower risk for disease-related events (HR 0.51, 95% CI 0.26-0.97, P = 0.04), but not with all-cause mortality or PCR-positivity.

Conclusions

SDC measurement decreases the risk for disease-related events, potentially through more optimal dosing or improved compliance. We recommend measurement of SDC and striving for SDC >5 μg/mL and <10 μg/mL during treatment of chronic Q fever.

Chronic Q fever-related complications and mortality: data from a nationwide cohort

OBJECTIVES

Chronic infection with Coxiella burnetii (chronic Q fever) can cause life-threatening conditions such as endocarditis, infected vascular prostheses, and infected arterial aneurysms. We aimed to assess prognosis of chronic Q fever patients in terms of complications and mortality.

METHODS

A large cohort of chronic Q fever patients was assessed to describe complications, overall mortality and chronic Q fever-related mortality. Chronic Q fever-related mortality was expressed as a case fatality rate (number of chronic Q fever-related deaths/number of chronic Q fever patients).

RESULTS

Complications occurred in 166 of 439 (38%) chronic Q fever patients: in 61% of proven (153/249), 15% of probable (11/74), and 2% of possible chronic Q fever patients (2/116). Most frequently observed complications were acute aneurysms (14%), heart failure (13%), and non-cardiac abscesses (10%). Overall mortality was 38% (94/249) for proven chronic Q fever patients (median follow-up 3.6 years) and 22% (16/74) for probable chronic Q fever patients (median follow-up 4.7 years). The case fatality rate was 25% for proven (63/249) chronic Q fever patients and 4% for probable (3/74) chronic Q fever patients. Overall survival was significantly lower in patients with complications, compared to those without complications (p <0.001).

CONCLUSIONS

In chronic Q fever patients, complications occur frequently and contribute to the mortality rate. Patients with proven chronic Q fever have the highest risk of complications and chronic Q fever-related mortality. Prognosis for patients with possible chronic Q fever is favourable in terms of complications and mortality.

Chronic Q fever: patient and treatment-related factors influencing long-term quality of life

BACKGROUND

Chronic Q fever is accompanied by high mortality and morbidity, and requires prolonged antibiotic treatment. Little is known on long-term quality of life (LQOL) in chronic Q fever patients treated with antibiotics.

AIM

To identify patient and treatment-related factors associated with impaired LQOL in chronic Q fever patients treated with antibiotics, and to assess patients' perception on treatment.

DESIGN

Cross-sectional study.

METHODS

LQOL was assessed with a validated questionnaire from the Nijmegen Clinical Screening Instrument. Patients' perception on treatment was measured with three newly developed questions.

RESULTS

We included 64 patients: LQOL was impaired in 55% (n = 35) after a median follow-up of 5 years. Median treatment duration was 27 months. In multivariable analysis, treatment duration was significantly associated with impaired LQOL (OR 1.07; 95%CI 1.02-1.12, P < 0.01 per month increase). Age, gender, number of antibiotic regimens, surgical intervention, complications, diagnostic classification, focus of infection or registration of side effects during treatment were not associated with impaired LQOL. After start of treatment, 17 patients (27%) perceived improvement of their condition. Disadvantages of treatment were experienced on a daily basis by 24 patients (69%) with impaired LQOL and 13 patients (46%) without impaired LQOL (P = 0.04).

CONCLUSIONS

LQOL in chronic Q fever patients treated with antibiotics is impaired in more than half of patients 5 years after diagnosis. Antibiotic treatment duration was the only variable associated with impaired LQOL. The majority of patients experienced disadvantages on a daily basis, highlighting the high burden of disease and treatment.

Referral of patients with fever of unknown origin to an expertise center has high diagnostic and therapeutic value

BACKGROUND

up to 50% of patients with fever of unknown origin (FUO) remain undiagnosed despite extensive evaluation. In expertise centers, at least 25-63% of these patients are referred after evaluation in another hospital. The diagnostic and therapeutic yields of referral to an expertise center are currently unknown.

AIM

To determine the diagnostic and therapeutic yield of referral of patients with fever of unknown origin (FUO) that remain undiagnosed in non-expertise hospitals.

DESIGN

Data on workup, outcome, treatment and prognosis were extracted from medical records of all 236 patients referred to the Radboud university medical center's department of internal medicine because of FUO between January 2005 and June 2014.

RESULTS

A final diagnosis could be made in 110 of 192 tertiary referred FUO patients. The rate of diagnosis did not differ between patients referred for first opinion or after tertiary referral (68.2 vs. 57.3%, P = 0.234). Over half of undiagnosed tertiary referred patients were treated, and fever resolved in half of these patients. Of 96 undiagnosed patients, two died (2.1)% and in both death was considered unrelated to the febrile disease.

CONCLUSION

The diagnostic rate in patients with FUO does not differ between patients that are tertiary referred and patients that have not been previously evaluated in another hospital. With a total diagnostic value of 57.3% and an additional therapeutic yield of 10.9% in undiagnosed patients, tertiary referral should therefore be considered in patients that remain undiagnosed in a non-expertise center.

Involvement of matrix metalloproteinases in chronic Q fever

OBJECTIVES

Chronic Q fever is a persistent infection with the intracellular Gram-negative bacterium Coxiella burnetii, which can lead to complications of infected aneurysms. Matrix metalloproteinases (MMPs) cleave extracellular matrix and are involved in infections as well as aneurysms. We aimed to study the role of MMPs in the pathogenesis of chronic Q fever.

METHODS

We investigated gene expression of MMPs through microarray analysis and MMP production with ELISA in C. burnetii-stimulated peripheral blood mononuclear cells (PBMCs) of patients with chronic Q fever and healthy controls. Twenty single nucleotide polymorphisms (SNPs) of MMP and tissue inhibitor of MMP genes were genotyped in 139 patients with chronic Q fever and 220 controls with similar cardiovascular co-morbidity. Additionally, circulating MMPs levels in patients with chronic Q fever were compared with those in cardiovascular controls with and without a history of past Q fever.

RESULTS

In healthy controls, the MMP pathway involving four genes (MMP1, MMP7, MMP10, MMP19) was significantly up-regulated in C. burnetii-stimulated but not in Escherichia coli lipopolysaccharide -stimulated PBMCs. Coxiella burnetii induced MMP-1 and MMP-9 production in PBMCs of healthy individuals (both p<0.001), individuals with past Q fever (p<0.05, p<0.01, respectively) and of patients with chronic Q fever (both p<0.001). SNPs in MMP7 (rs11568810) (p<0.05) and MMP9 (rs17576) (p<0.05) were more common in patients with chronic Q fever. Circulating MMP-7 serum levels were higher in patients with chronic Q fever (median 33.5 ng/mL, interquartile range 22.3-45.7 ng/mL) than controls (20.6 ng/mL, 15.9-33.8 ng/mL).

CONCLUSION

Coxiella burnetii-induced MMP production may contribute to the development of chronic Q fever.

Intact interferon-γ response against Coxiella burnetii by peripheral blood mononuclear cells in chronic Q fever

OBJECTIVES

Q fever is caused by Coxiella burnetii, an intracellular bacterium that infects phagocytes. The aim of the present study was to investigate whether the C. burnetii-induced IFN-γ response is defective in chronic Q fever patients.

METHODS

IFN-γ was measured in supernatants of C. burnetii-stimulated peripheral blood mononuclear cells (PBMCs) of 17 chronic Q fever patients and 17 healthy individuals. To assess IFN-γ responses, expression profiles of IFN-γ-induced genes in C. burnetii-stimulated PBMCs were studied in six patients and four healthy individuals. Neopterin was measured in PBMC supernatants (of eight patients and four healthy individuals) and in sera (of 21 patients and 11 healthy individuals). In a genetic association study, polymorphisms in genes involved in the Th1-cytokine response were analysed in a cohort of 139 chronic Q fever patients and a cohort of 220 control individuals with previous exposition to C. burnetii.

RESULTS

IFN-γ production by C. burnetii-stimulated PBMCs from chronic Q fever patients was significantly higher than in healthy controls. Many IFN-γ response genes were strongly upregulated in PBMCs of patients. Neopterin levels were significantly higher in PBMC supernatants and sera of patients. The IL12B polymorphisms rs3212227 and rs2853694 were associated with chronic Q fever.

CONCLUSIONS

IFN-γ production, as well as the response to IFN-γ, is intact in chronic Q fever patients, and even higher than in healthy individuals. Polymorphisms in the IL-12p40 gene are associated with chronic Q fever. Thus, a deficiency in IFN-γ responses does not explain the failure to clear the infection. The genetic data suggest, however, that the IL-12/IFN-γ pathway does play a role.

Association of esophageal candidiasis and squamous cell carcinoma

Chronic esophageal candidiasis is an infection that is mostly seen in immunocompromised conditions, among which is chronic mucocutaneous candidiasis (CMC). Recently an association between CMC and esophageal carcinoma has been reported. Here we present two patients with chronic esophageal candidiasis who developed esophageal squamous cell carcinoma and we discuss the etiologic role of Candida-induced nitrosamine production, the loss of STAT1 function and impaired tumor surveillance and T-lymphocyte function in the development of esophageal carcinoma.

Endocarditis: effects of routine echocardiography during Gram-positive bacteraemia

BACKGROUND

Despite firm recommendations to perform echocardiography in high-risk patients with Gram-positive bacteraemia, routine echocardiography is not embedded in daily practice in many settings. The aim of this study was to evaluate whether a regime including routine echocardiography results in better outcome.

METHODS

A total of 115 patients with Gram-positive bacteraemia and at least one risk factor for developing metastatic infection were prospectively included. Routine echocardiography was advocated and facilitated in these patients. Results were compared with a matched historical control group of 230 patients in whom echocardiography was performed at the discretion of the attending physician. Endocarditis was diagnosed according to the Duke criteria.

RESULTS

Echocardiography was performed more often in the study group (82 vs 27%, p.

Q fever in the Netherlands from 2007 to 2010

Since 2007, the Netherlands is faced with the largest outbreak of Q fever ever reported. In the last four years, over 4000 cases have been reported. The course of the epidemic and possible factors associated with this sudden surge in cases of Q fever is described and the preventive measures in the veterinary sector and the outbreak management of this unique epidemic are summarised. Finally, the latest data on clinical presentation and diagnostic and therapeutic dilemmas of Q fever in the Netherlands are reviewed.

Internal medicine residents' knowledge about sepsis: effects of a teaching intervention

The short- and long-term effects of a single teaching intervention for internal medicine residents are not known. Since sepsis is a prevalent and important disease and both therapeutic and diagnostic interventions have been protocolized, we investigated the effects of a sepsis-based single teaching intervention. A prospective before-and-after education study was performed among residents who attended a regional professional training for internal medicine. All residents who participated were invited to complete a questionnaire about the assessment of symptoms and the diagnosis and treatment of sepsis. The questionnaire was filled out before, directly after, and four to six months after the teaching intervention. The overall questionnaire score was expressed on a 0 to 10 scale. A total of 253 questionnaires from 109 training-grade doctors were collected. At baseline, the 'assessment of symptoms of sepsis' score was significantly lower than the 'diagnosis and treatment' score. Following the education session, training-grade doctors' knowledge about sepsis definitions and diagnosis and treatment of sepsis increased from (mean +/- SD ) 6.1 +/- 1.6 to 8.2 +/- 1.2 (p<0.0001. Moreover, four to six months after the teaching intervention, this effect was sustained (p<0.0001 compared with test 1), resulting in a mean score of 7.6 +/- 1.1. Our single teaching intervention resulted in improved and sustained knowledge on the assessment of symptoms, diagnosis and treatment of sepsis.

Pylephlebitis after a duodenal ulcer in a patient with metastasised colon carcinoma treated with chemotherapy and bevacizumab: a case report

Pylephlebitis or septic thrombophlebitis of the portal vein is a rare entity with a high mortality rate. It is often a complication of intra-abdominal infection most commonly caused by diverticulitis and appendicitis. Diagnosis is often delayed since clinical signs and symptoms are nonspecific. Pylephlebitis should be considered in patients with sepsis due to gut-associated organisms without a clear focus of infection. We describe a patient with metastastatic colon carcinoma treated with chemotherapy and bevacizumab who was diagnosed with pylephlebitis after a duodenal ulcer and responded well to antibiotic treatment.

[Diagnostic approach to fever of unknown origin]

Nowadays, fever of unknown origin (FUO) is generally defined as a fever higher than 38-3 degrees C lasting for a period of at least three weeks, in which no definitive diagnosis has been made after a number of obligatory tests. A diagnostic algorithm is proposed in which history taking, physical examination and the obligatory tests are the most important steps in the search for potentially diagnostic clues (PDCs). Next, factitious fever and drug fever should be ruled out. Further diagnostic procedures should be guided by the PDCs. If this does not lead to diagnosis or if there are no useful PDCs, further screening, including 18F-fluorodeoxyglucose positron emission tomography, should be performed. In 30 to 50% of the patients with FUO no diagnosis can be reached. If their clinical condition is stable, waiting to see if new PDCs develop is recommended. Most patients in whom no diagnosis can be made, have a good prognosis. Supportive treatment with NSAIDs can be helpful. Only if patients deteriorate, should other therapeutic trials be considered.

Imaging of infectious diseases using [18F] fluorodeoxyglucose PET

The role of fluorodeoxyglucose positron emission tomography (FDG PET) in the diagnostic localization of infectious diseases has expanded rapidly in years. In general, sensitivity of FDG PET in depicting infections compares favorably to other diagnostic modalities . It is shown to be useful in patients with suspected osteomyelitis, especially in chronic low grade infections and in vertebral osteomyelitis. although the sensitivity of FDG PET in prosthetic joint infections is very high, reported specificity varies considerably. In experienced centers, FDG uptake localized along the interface between bone and prosthesis can be used to diagnose infection with acceptable specificity. Combined leukocyte scintigraphy and bone scanning, however, remains the standard scintigraphic method for diagnosis of infected joint prostheses. FDG PET has shown promising results in vascular graft infections, in the evaluation of metastatic infectious foci inpatients with blood stream infections and in neutropenic patients, but further studies are needed before definitive conclusions can be drawn . In fever of unknown origin (FUO), FDG PET appears to be of great advantage as malignancy, inflammation and infection can be detected. Image fusion combining PET and computed tomography facilitates anatomical localization of increased FDG uptake and better guiding for further diagnostic tests to achieve a final diagnosis. In conclusion, the body of evidence on utility of FDG PET in infectious diseases and FUO is growing and FDG PET may become one of the preferred diagnostic procedures for many of these diseases, especially when a definite diagnosis cannot easily be achieved.

Complicating infectious foci in patients with Staphylococcus aureus or Streptococcus species bacteraemia

Complicating infectious foci resulting from haematogenous or local spread of microorganisms are observed frequently in patients with Staphylococcus aureus bacteraemia (SAB) or Streptococcus species bacteraemia (SSB). The aim of this study was to compare the epidemiology of complicating infectious foci during SAB and SSB in a university hospital in The Netherlands. The charts of all adult patients diagnosed with SAB or SSB (except for Streptococcus pneumoniae bacteraemia) from July 2002 until December 2004 were reviewed retrospectively. Overall, 180 immunocompetent patients were identified, 127 with SAB and 53 with SSB. The percentage of patients with complicating infectious foci (39% of SAB patients, 25% of SSB patients) did not differ significantly between the groups. Endocarditis and cerebral involvement, however, were significantly more common in the SSB group. Of all complicating infectious foci, 32% lacked guiding signs or symptoms and 10% were detected only at autopsy. Factors associated with the development of complicating infectious foci were a delay in treatment for more than 48 h after the onset of symptoms, community acquisition, persistently positive blood cultures, congenital heart disease, and the presence of foreign bodies or prosthetic valves. Infection-related mortality was 18% in SAB patients and 11% in SSB patients and was significantly higher in patients with complicating infectious foci (29 vs. 9%). In conclusion, complicating infectious foci develop in approximately one-third of all patients with SAB and SSB. An active approach that entails searching for the complicating infectious foci is warranted in these patients, because only two-thirds of complicated infectious foci have guiding symptoms or signs, and infection-related mortality is significantly increased in patients with complicating infectious foci compared to patients without these infections.

FDG-PET for imaging of non-osseous infection and inflammation

FDG-PET is emerging as a promising imaging technique in non-osseous infectious and inflammatory diseases, as an increasing number of reports are appearing in literature. In general, sensitivity of FDG-PET in diagnosing non-osseous infections compares favorably to other diagnostic modalities. Lower specificity due to FDG accumulation in conditions involving leukocyte activation and malignancy may be overcome by implementing FDG-PET in a diagnostic protocol. In fever of unknown origin, FDG-PET appears to be of great advantage as malignancy, inflammation and infection can be detected. Studies on standardized uptake value ratios, uptake patterns and dynamics may be helpful to increase specificity. Image fusion combining PET and CT facilitates anatomical localization of increased FDG-uptake and better guiding for further diagnostic tests to achieve a final diagnosis. More data on the utility of FDG-PET to monitor the response to treatment will be available in near future. Early reports on FDG-PET during treatment follow-up in large vessel vasculitis already showed promising

RESULTS

In conclusion, the body of evidence on the utility of FDG-PET in non-osseous infection and inflammation is growing and FDG-PET may become one of the preferred diagnostic procedures for these diseases.

Aortitis Diagnosed by F–18–Fluorodeoxyglucose Positron Emission Tomography in a Patient with Syphilis and HIV Coinfection

The most common manifestation of cardiovascular syphilis, a rare diagnosis since the introduction of penicillin, is aortitis of the ascending aorta. Since the majority of patients with uncomplicated aortitis are asymptomatic, early diagnosis is difficult. We report the case of an HIV-positive patient with asymptomatic syphilitic aortitis that was incidentally diagnosed with F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET). We conclude that FDG-PET could become a promising new imaging technique for both diagnosis and follow-up of patients with syphilitic aortitis.

Diagnosis of Candida lung abscesses by 18F-fluorodeoxyglucose positron emission tomography

In three patients with catheter-associated candidaemia, use of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) led to the diagnosis of Candida lung abscesses, which was confirmed by computed tomography and a favourable response to antifungal therapy. It was concluded that FDG-PET is a promising new imaging technique that enables early identification of sites of disseminated candidiasis, and that this technique can be used in the evaluation of therapy.

Radiolabeled compounds in diagnosis of infectious and inflammatory disease

Nuclear medicine offers powerful noninvasive techniques for visualization of infectious and inflammatory disorders using whole body imaging enabling the determination of both localization and number of inflammatory foci. A wide variety of approaches depicting the different stages of the inflammatory response have been developed. Non-specific radiolabeled compounds, such as 67Ga-citrate and radiolabeled polyclonal human immunoglobulin accumulate in inflammatory foci due to enhanced vascular permeability. Specific accumulation of radiolabeled compounds in inflammatory lesions results from binding to activated endothelium (e.g. radiolabeled anti-E-selectin), the enhanced influx of leukocytes (e.g. radiolabeled autologous leukocytes, anti-granulocyte antibodies or cytokines), the enhanced glucose-uptake by activated leukocytes (18F-fluorodeoxyglucose) or direct binding to micro-organisms (e.g. radiolabeled ciprofloxacin or antimicrobial peptides). Scintigraphy using autologous leukocytes, labeled with 111In or 99mTc, is still considered the "gold standard" nuclear medicine technique for the imaging of infection and inflammation, but the range of radiolabeled compounds available for this indication is still expanding. Recently, positron emission tomography with 18F-fluorodeoxyglucose has been shown to delineate various infectious and inflammatory disorders with high sensitivity. New developments in peptide chemistry and in radiochemistry will result in specific agents with high specific activity. A gradual shift from non-specific, cumbersome or even hazardous approaches to more sophisticated, specific approaches is ongoing. In this review, the different approaches to scintigraphic imaging of infection and inflammation, already in use or under investigation, are discussed.

F-18-fluorodeoxyglucose positron emission tomography leading to a diagnosis of septic thrombophlebitis of the portal vein: description of a case history and review of the literature

Pylephlebitis or septic thrombophlebitis of the portal vein is a serious infectious disorder. Early diagnosis is difficult, due to nonspecific symptoms and signs, limitations of diagnostic modalities and the lack of familiarity of physicians with this entity. We report the history of a 73-year-old man with fever of unknown origin (FUO) in whom laboratory tests, blood and urine cultures, chest X-ray, abdominal ultrasound, and Indium-111-leucocyte scintigraphy did not reveal the cause of the fever. F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET) subsequently pointed to the diagnosis of pylephlebitis, which was confirmed by computed tomography (CT) and percutaneous puncture. We conclude that FDG PET allows detecting inflammatory foci in patients with FUO and offers to make the diagnosis of pylephlebitis at an early stage.

F-18-fluorodeoxyglucose positron emission tomography in diagnosis and follow-up of patients with different types of vasculitis

BACKGROUND

F-18-fluorodeoxyglucose (FDG) accumulates in inflammatory cells due to an increased metabolic rate. Therefore, FDG positron emission tomography (PET) represents a promising imaging technique in patients with vasculitis. The aim of this study was to assess the value of FDG PET in the diagnosis of different types of vasculitis.

METHODS

The results of FDG PET performed because of suspected vasculitis or fever of unknown origin with results indicating vasculitis were reviewed. These results were compared with the final diagnosis, based on the American College of Rheumatology 1990 criteria.

RESULTS

FDG PET was ordered because of suspected vasculitis in 20 patients, because of fever of unknown origin in two patients, and for follow-up of vasculitis in five patients. Fourteen patients were diagnosed with vasculitis (giant cell arteritis n = 5, polymyalgia rheumatica n = 2, polyarteritis nodosa n = 3, Takayasu n = 1, Churge-Strauss n = 1, Wegener's granulomatosis n = 1, vasculitis skin n = 1), two patients were diagnosed with fibromuscular dysplasia and one patient had media necrosis of the aorta. In five patients no diagnosis could be reached. FDG PET results were considered to be true-positive in ten patients, true-negative in 14 patients and false-negative in three patients resulting in a positive predictive value of 100% and a negative predictive value of 82%.

CONCLUSIONS

FDG PET appears to be a promising new imaging technique in diagnosing and determining the extent of various forms of vasculitis. Furthermore, FDG PET may become a useful tool for evaluating the effect of treatment of vasculitis.

Tension pneumopericardium caused by positive pressure ventilation complicating anaerobic pneumonia

A 22-year-old man was admitted with pneumonia. He was immediately intubated and positive pressure ventilation was initiated. Blood and sputum cultures showed Bacteroides fragilis and Corynebacterium sp., which were treated with metronidazole and clindamycin. Three weeks later his blood pressure suddenly dropped with an elevation of the central venous pressure. Chest X-ray revealed a pneumopericardium. A parasternal mediastinotomy with partial pericardiectomy was immediately performed. On opening the pericardium his blood pressure normalised. The patient gradually recovered and six weeks after admission he was extubated. Two weeks later he was discharged. A pneumopericardium without previous thorax trauma is very rare and early recognition is imperative because a tension pneumopericardium with cardiac tamponade may develop, as happened in this case. A tension pneumopericardium has to be treated with immediate pericardiocentesis followed by partial pericardiectomy to avoid recurrence.

Hepatic steatosis and lactic acidosis caused by stavudine in an HIV-infected patient

Lactic acidosis and hepatic steatosis caused by mitochondrial toxicity of nucleoside reverse transcriptase inhibitors (NRTI) is a rare cause of liver disease with a high mortality rate. This report describes a male, HIV-positive patient with a 4-week history of nausea, vomiting and abdominal pain. His medication consisted of prednisone 5 mg od (because of auto-immune thrombocytopenia), didanosine (for 2 years) and stavudine (for 3 months). Laboratory studies showed cholestasis and elevation of aminotransferases. Lactic level was not measured. Liver biopsy revealed steatosis and cholestatic hepatitis. In the absence of other causes of liver disease a probable diagnosis of stavudine-induced hepatic toxicity was made. After discontinuation of NRTI, he recovered completely. Because lactic acidosis had not been confirmed, stavudine was restarted and within 1 week the lactate level increased significantly. Therefore stavudine was discontinued again. One year later the patient is doing well on a double protease inhibitor regimen. In conclusion, clinicians treating patients with NRTI should be aware of the risk of lactic acidosis and hepatic steatosis. When this is suspected, all NRTI must be stopped. The diagnosis can be made when elevated lactate levels and hepatic steatosis are present in the absence of other causes of liver disease.