Cytometry profiling of ex vivo recall responses to Coxiella burnetii in previously naturally exposed individuals reveals long-term changes in both adaptive and innate immune cellular compartments

Abstract:

Introduction: Q fever, caused by the intracellular bacterium Coxiella burnetii, is considered an occupational and biodefense hazard and can result in debilitating long-term complications. While natural infection and vaccination induce humoral and cellular immune responses, the exact nature of cellular immune responses to C. burnetii is incompletely understood. The current study seeks to investigate more deeply the nature of long-term cellular recall responses in naturally exposed individuals by both cytokine release assessment and cytometry profiling.

Methods: Individuals exposed during the 2007-2010 Dutch Q fever outbreak were grouped in 2015, based on a C. burnetii-specific IFNγ release assay (IGRA), serological status, and self-reported clinical symptoms during initial infection, into asymptomatic IGRA-negative/seronegative controls, and three IGRA-positive groups (seronegative/asymptomatic; seropositive/asymptomatic and seropositive/symptomatic). Recall responses following in vitro re-stimulation with heat-inactivated C. burnetii in whole blood, were assessed in 2016/2017 by cytokine release assays (n=55) and flow cytometry (n=36), and in blood mononuclear cells by mass cytometry (n=36).

Results: Cytokine release analysis showed significantly elevated IL-2 responses in all seropositive individuals and elevated IL-1β responses in those recovered from symptomatic infection. Comparative flow cytometry analysis revealed significantly increased IFNγ, TNFα and IL-2 recall responses by CD4 T cells and higher IL-6 production by monocytes from symptomatic, IGRA-positive/seropositive individuals compared to controls. Mass cytometry profiling and unsupervised clustering analysis confirmed recall responses in seropositive individuals by two activated CD4 T cell subsets, one characterized by a strong Th1 cytokine profile (IFNγ+IL-2+TNFα+), and identified C. burnetii-specific activation of CD8 T cells in all IGRA-positive groups. Remarkably, increased C. burnetii-specific responses in IGRA-positive individuals were also observed in three innate cell subpopulations: one characterized by an IFNγ+IL-2+TNFα+ Th1 cytokine profile and lack of canonical marker expression, and two IL-1β-, IL-6- and IL-8-producing CD14+ monocyte subsets that could be the drivers of elevated secretion of innate cytokines in pre-exposed individuals.

Discussion: These data highlight that there are long-term increased responses to C. burnetii in both adaptive and innate cellular compartments, the latter being indicative of trained immunity. These findings warrant future studies into the protective role of these innate responses and may inform future Q fever vaccine design.

Source: Raju Paul S, Scholzen A, Reeves PM, Shepard R, Hess JM, Dzeng RK, Korek S, Garritsen A, Poznansky MC, Sluder AE. Cytometry profiling of ex vivo recall responses to Coxiella burnetii in previously naturally exposed individuals reveals long-term changes in both adaptive and innate immune cellular compartments. Front Immunol. 2023 Oct 11;14:1249581. doi: 10.3389/fimmu.2023.1249581. PMID: 37885896; PMCID: PMC10598782. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10598782/ (Full text)

Long-term health outcomes of Q-fever fatigue syndrome patients

Summary:

This study determined long-term health outcomes (≥10 years) of Q-fever fatigue syndrome (QFS). Longterm health complaints, health-related quality of life (HRQL), health status, energy level, fatigue, post exertional malaise, anxiety and depression were assessed. Outcomes and determinants were studied for the total sample and compared among age subgroups: young (<40y), middle-aged (≥40-<65y), and older
(≥65y) patients.

368 QFS patients were included. Participants reported a median number of 12.0 long-term health complaints. Their HRQL (median EQ-5D-5L index: 0.63) and health status (median EQ VAS: 50.0) were low, their level of fatigue was high, and many experienced post-exertional malaise complaints (98.9%). Young and middle-aged patients reported worse health outcomes compared to older patients, with both groups reporting a significantly worse health status, higher fatigue levels and anxiety, and more post-exertional malaise complaints; and middle-aged patients having a lower HRQL and a higher risk of depression.

Multivariate regression analyses confirmed that older age is associated with better outcomes, except for the number of health complaints. QFS has thus a considerable impact on patients’ health more than 10 years after infection. Young and middle-aged patients experience more long-term health consequences compared to older patients. Tailored healthcare is recommended to provide optimal care for each QFS patient.

Source: Spronk, I., Brus, I., Groot, A., Tieleman, P., Olde Loohuis, A., Haagsma, J., & Polinder, S. (2023). Long-term health outcomes of Q-fever fatigue syndrome patients. Epidemiology & Infection, 1-35. doi:10.1017/S0950268823001401 https://www.cambridge.org/core/journals/epidemiology-and-infection/article/longterm-health-outcomes-of-qfever-fatigue-syndrome-patients/99B3D80E172A66619C216506E020BB02 (Full text available as PDF file)

Identifying disrupted biological factors and patient-tailored interventions for chronic fatigue in adolescents and young adults with Q-Fever Fatigue Syndrome, Chronic Fatigue Syndrome and Juvenile Idiopathic Arthritis (QFS-study): study protocol for a randomized controlled trial with single-subject experimental case series design

Abstract:

Background: Chronic fatigue with a debilitating effect on daily life is a frequently reported symptom among adolescents and young adults with a history of Q-fever infection (QFS). Persisting fatigue after infection may have a biological origin with psychological and social factors contributing to the disease phenotype. This is consistent with the biopsychosocial framework, which considers fatigue to be the result of a complex interaction between biological, psychological, and social factors. In line, similar manifestations of chronic fatigue are observed in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and juvenile idiopathic arthritis (JIA). Cognitive behavioral therapy is often recommended as treatment for chronic fatigue, considering its effectiveness on the group level. However, not everybody benefits on the individual level. More treatment success at the individual level might be achieved with patient-tailored treatments that incorporate the biopsychosocial framework.

Methods: In addition to biological assessments of blood, stool, saliva, and hair, the QFS-study consists of a randomized controlled trial (RCT) in which a single-subject experimental case series (N=1) design will be implemented using Experience Sampling Methodology in fatigued adolescents and young adults with QFS, CFS/ME, and JIA (aged 12-29). With the RCT design, the effectiveness of patient-tailored PROfeel lifestyle advices will be compared against generic dietary advices in reducing fatigue severity at the group level. Pre-post analyses will be conducted to determine relevance of intervention order. By means of the N=1 design, effectiveness of both advices will be measured at the individual level.

Discussion: The QFS-study is a comprehensive study exploring disrupted biological factors and patient-tailored lifestyle advices as intervention in adolescent and young adults with QFS and similar manifestations of chronic fatigue. Practical or operational issues are expected during the study, but can be overcome through innovative study design, statistical approaches, and recruitment strategies. Ultimately, the study aims to contribute to biological research and (personalized) treatment in QFS and similar manifestations of chronic fatigue.

Trial registration: Trial NL8789 . Registered July 21, 2020.

Source: Vroegindeweij A, Swart JF, Houtveen J, Eijkelkamp N, van de Putte EM, Wulffraat NM, Nijhof SL. Identifying disrupted biological factors and patient-tailored interventions for chronic fatigue in adolescents and young adults with Q-Fever Fatigue Syndrome, Chronic Fatigue Syndrome and Juvenile Idiopathic Arthritis (QFS-study): study protocol for a randomized controlled trial with single-subject experimental case series design. Trials. 2022 Aug 19;23(1):683. doi: 10.1186/s13063-022-06620-2. PMID: 35986408.  https://trialsjournal.biomedcentral.com/articles/10.1186/s13063-022-06620-2 (Full text)

 

Predictors of Chronic Fatigue Syndrome and Mood Disturbance After Acute Infection

Abstract:

Prospective cohort studies following individuals from acute infections have documented a prevalent post-infective fatigue state meeting diagnostic criteria for chronic fatigue syndrome (CFS) – that is, a post-infective fatigue syndrome (PIFS). The Dubbo Infection Outcomes Study (DIOS) was a prospective cohort following individuals from acute infection with Epstein-Barr virus (EBV), Ross River virus (RRV), or Q fever through to assessment of caseness for CFS designated by physician and psychiatrist assessments at 6 months. Previous studies in DIOS have revealed that functional genetic polymorphisms in both immunological (pro- and anti-inflammatory cytokines) and neurological (the purinergic receptor, P2X7) genes are associated with both the severity of the acute infection and subsequent prolonged illness.

Principal components analysis was applied to self-report data from DIOS to describe the severity and course of both the overall illness and concurrent mood disturbance. Associations between demographics and acute infection characteristics, with prolonged illness course as well as the PIFS outcome were examined using multivariable statistics. Genetic haplotype-driven functional variations in the neuropeptide Y (NPY) gene previously shown to be associated with brain responses to stress, and to trait anxiety were also examined as predictors.

The sample included 484 subjects (51% female, median age 32, IQR 19-44), of whom 90 (19%) met diagnostic criteria for CFS at 6 months. Participants with greater overall illness severity and concurrent mood disturbance in the acute illness had a more prolonged illness severity (HR = 0.39, 95% CI: 0.34-0.46, p < 0.001) and mood disturbance (HR = 0.36, 95% CI: 0.30-0.42, p < 0.001), respectively. Baseline illness severity and RRV infection were associated with delayed recovery.

Female gender and mood disturbance in the acute illness were associated with prolonged mood disturbance. Logistic regression showed that the odds of an individual being diagnosed with PIFS increased with greater baseline illness severity (OR = 2.24, 95% CI: 1.71-2.94, p < 0.001). There was no association between the NPY haplotypes with overall illness severity or mood disturbance either during the acute illness phase or with prolonged illness (p > 0.05). Severe acute infective illnesses predicted prolonged illness, prolonged mood disturbance and PIFS. These factors may facilitate early intervention to manage both PIFS and mood disturbances.

Source: Sandler CX, Cvejic E, Valencia BM, Li H, Hickie IB, Lloyd AR. Predictors of Chronic Fatigue Syndrome and Mood Disturbance After Acute Infection. Front Neurol. 2022 Jul 25;13:935442. doi: 10.3389/fneur.2022.935442. PMID: 35959390; PMCID: PMC9359311. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9359311/ (Full text)

Impact of Q-fever on physical and psychosocial functioning until 8 years after Coxiella burnetii infection: An integrative data analysis

Abstract:

Background: This study aimed to determine short- and long-term physical and psychosocial impact of Coxiella burnetii infection in three distinct entities: Q-fever fatigue syndrome (QFS), chronic Q-fever, and patients with past acute Q-fever without QFS or chronic Q-fever.

Methods: Integrative data analysis was performed, combining original data from eight studies measuring quality of life (QoL), fatigue, physical and social functioning with identical validated questionnaires, from three months to eight years after onset infection. Linear trends in each outcome were compared between Q-fever groups using multilevel linear regression analyses to account for repeated measures within patients.

Results: Data included 3947 observations of 2313 individual patients (228 QFS, 135 chronic Q-fever and 1950 patients with past acute Q-fever). In the first years following infection, physical and psychosocial impact was highest among QFS patients, and remained high without significant improvements over time. In chronic Q-fever patients, QoL and physical functioning worsened significantly over time. Levels of fatigue and social participation in patients with past acute Q-fever improved significantly over time.

Conclusion: The impact differs greatly between the three Q-fever groups. It is important that physicians are aware of these differences, in order to provide relevant care for each patient group.

Source: Reukers DFM, van Jaarsveld CHM, Akkermans RP, Keijmel SP, Morroy G, van Dam ASG, Wever PC, Wielders CCH, van der Velden K, van Loenhout JAF, Hautvast JLA. Impact of Q-fever on physical and psychosocial functioning until 8 years after Coxiella burnetii infection: An integrative data analysis. PLoS One. 2022 Feb 2;17(2):e0263239. doi: 10.1371/journal.pone.0263239. PMID: 35108330; PMCID: PMC8809529. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0263239 (Full text)

Incidence of chronic Q fever and chronic fatigue syndrome: a six year follow-up of a large Q fever outbreak

Abstract:

Objectives: Acute Q fever is a generally self-limiting infection caused by the intracellular gram-negative bacterium Coxiella (C.) burnetii. For yet unknown reasons, a subset of patients develops chronic a infection. Furthermore, a Chronic Fatigue Syndrome (CFS) as post-acute Q fever sequelae has been described. We here investigated the rates of chronic Q fever and incidences of CFS six years after one of the largest European Q fever outbreaks that occurred in Jena, Germany in 2005 with 331 reported cases, who lived in proximity of a grazing sheep herd.

Methods: A total of 80 patients and 52 non-diseased household members from the former outbreak, were enrolled six years after the outbreak, blood samples collected and tested for a chronic Q fever were determined by seroprevalence using referenced immunofluorescence tests. Also, the presence of a CFS was assessed using the Short Form Symptom Inventory developed by the Centers (United States) for Disease Control and Prevention (SF CDC- SI).

Results: In 80 out of 132 (60.6%) study participants, previous Q fever infection was confirmed serologically, while no previous infection was detected in the 52 household members. None of the participants fulfilled the serological criteria of chronic Q fever. The evaluation of the CDC-SI did not show any differences between the two groups. Also, there was no difference between both groups regarding fulfillment of CFS-defining criteria (n = 3 (3.8 %; sero-positive) vs. n = 2 (3.8 %; sero-negative), p = 0.655).

Conclusion: Our six-year follow-up study of a large Q fever outbreak did not find evidence for chronic Q fever or post Q fever CFS. There was no asymptomatic sero-positivity in household members of Q fever patients.

Source: Ankert J, Frosinski J, Weis S, Boden K, Pletz MW. Incidence of chronic Q fever and chronic fatigue syndrome: a six year follow-up of a large Q fever outbreak. Transbound Emerg Dis. 2021 Jul 9. doi: 10.1111/tbed.14224. Epub ahead of print. PMID: 34240822. https://pubmed.ncbi.nlm.nih.gov/34240822/

Utility of positron emission tomography imaging in the diagnosis of chronic Q fever: A Systematic Review

Abstract:

Chronic Q fever is a diagnostic challenge. Diagnosis relies on serology and/or the detection of DNA from blood or tissue samples. PET-CT identifies tissues with increased glucose metabolism, thus identifying foci of inflammation. Our aim was to review the existing literature on the use of PET-CT to help diagnose chronic Q fever. A literature search was conducted in PubMed and Google Scholar to ascertain publications that included the terms ‘Positron Emission Tomography’ and ‘PET CT’ in combination with subheadings ‘chronic Q fever’ and ‘Coxiella burnetii’ within the search. To broaden our search retrieval, we used the terms ‘chronic Q fever’ and ‘PET-CT’.

Published literature up to 16th April 2020 was included. 274 articles were initially identified. Post-exclusion criteria, 46 articles were included. Amongst case reports and series, the most frequent focus of infection was vascular, followed by musculoskeletal then cardiac. 79.5% of patients had a focus detected with 55.3% of these having proven infected prosthetic devices. Amongst the retrospective and prospective studies, a total of 394 positive sites of foci were identified with 186 negative cases. Some had follow-up scans (53), with 75.5% showing improvement or resolution. Average timeframe for documented radiological resolution post-initiating treatment was 8.86 months.

PET-CT is a useful tool in the management of chronic Q fever. Knowledge of a precise focus enables for directed surgical management helping reduce microbial burden, preventing future complications. Radiological resolution of infection can give clinicians reassurance on whether antimicrobial therapy can be ceased earlier, potentially limiting side effects.

Source: Sivabalan P, Visvalingam R, Grey V, Blazak J, Henderson A, Norton R. Utility of positron emission tomography imaging in the diagnosis of chronic Q fever: A Systematic Review. J Med Imaging Radiat Oncol. 2021 May 30. doi: 10.1111/1754-9485.13244. Epub ahead of print. PMID: 34056851. https://pubmed.ncbi.nlm.nih.gov/34056851/

Could Cognitive Behavioural Therapy Be an Effective Treatment for Long COVID and Post COVID-19 Fatigue Syndrome? Lessons from the Qure Study for Q-Fever Fatigue Syndrome

Abstract:

An increasing number of young and previously fit and healthy people who did not require hospitalisation continue to have symptoms months after mild cases of COVID-19. Rehabilitation clinics are already offering cognitive behavioural therapy (CBT) as an effective treatment for long COVID and post-COVID-19 fatigue syndrome based on the claims that it is effective for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)-the most common post-infectious syndrome-as no study into the efficacy of CBT for post-COVID-19 fatigue syndrome has been published. Re-analyses of these studies, however, showed that CBT did not lead to objective improvements in heterogeneous groups of ME/CFS patients, nor did it restore the ability to work.

The group of patients with long COVID and post-COVID-19 fatigue syndrome, on the other hand, is homogeneous. We therefore analysed the Dutch Qure study, as it studied the efficacy of CBT in a homogeneous group of patients who developed Q-fever fatigue syndrome-which affects up to 30% of patients-after the largest reported outbreak of Q-fever, to see if CBT might potentially be an effective treatment for long-haulers after COVID-19 infection.

Our reanalysis found that the Qure study suffered from many serious methodological problems, which included relying on one subjective primary outcome in a study without a control group for the non-blinded CBT treatment group, using a post hoc definition of improvement, waiting 2 years before publishing their objective actometer results and ignoring the null effect of said results. Moreover, only 10% of participants achieved a clinically meaningful subjective improvement in fatigue as a result of CBT according to the study’s own figures.

Consequently, CBT has no subjective clinically meaningful effect in nine out of every ten patients that are treated with it. Additionally, the subjective improvement in fatigue was not matched by an improvement in disability, even though the disability was fatigue related according to the researchers. On top of this, CBT did not lead to an objective improvement in physical performance. Therefore, it cannot be said that CBT is an effective treatment for Q-fever fatigue syndrome either. It seems therefore unlikely that CBT will reduce disability or lead to objective improvement in long COVID or in post-COVID-19 fatigue syndrome.

Source: Vink M, Vink-Niese A. Could Cognitive Behavioural Therapy Be an Effective Treatment for Long COVID and Post COVID-19 Fatigue Syndrome? Lessons from the Qure Study for Q-Fever Fatigue Syndrome. Healthcare (Basel). 2020 Dec 11;8(4):E552. doi: 10.3390/healthcare8040552. PMID: 33322316. https://www.mdpi.com/2227-9032/8/4/552 (Full text)

Multi-omics examination of Q fever fatigue syndrome identifies similarities with chronic fatigue syndrome

Abstract:

Background: Q fever fatigue syndrome (QFS) is characterised by a state of prolonged fatigue that is seen in 20% of acute Q fever infections and has major health-related consequences. The molecular mechanisms underlying QFS are largely unclear. In order to better understand its pathogenesis, we applied a multi-omics approach to study the patterns of the gut microbiome, blood metabolome, and inflammatory proteome of QFS patients, and compared these with those of chronic fatigue syndrome (CFS) patients and healthy controls (HC).

Methods: The study population consisted of 31 QFS patients, 50 CFS patients, and 72 HC. All subjects were matched for age, gender, and general geographical region (South-East part of the Netherlands). The gut microbiome composition was assessed by Metagenomic sequencing using the Illumina HiSeq platform. A total of 92 circulating inflammatory markers were measured using Proximity Extension Essay and 1607 metabolic features were assessed with a high-throughput non-targeted metabolomics approach.

Results: Inflammatory markers, including 4E-BP1 (P = 9.60-16 and 1.41-7) and MMP-1 (P = 7.09-9 and 3.51-9), are significantly more expressed in both QFS and CFS patients compared to HC. Blood metabolite profiles show significant differences when comparing QFS (319 metabolites) and CFS (441 metabolites) patients to HC, and are significantly enriched in pathways like sphingolipid (P = 0.0256 and 0.0033) metabolism. When comparing QFS to CFS patients, almost no significant differences in metabolome were found. Comparison of microbiome taxonomy of QFS and CFS patients with that of HC, shows both in- and decreases in abundancies in Bacteroidetes (with emphasis on Bacteroides and Alistiples spp.), and Firmicutes and Actinobacteria (with emphasis on Ruminococcus and Bifidobacterium spp.). When we compare QFS patients to CFS patients, there is a striking resemblance and hardly any significant differences in microbiome taxonomy are found.

Conclusions: We show that QFS and CFS patients are similar across three different omics layers and 4E-BP1 and MMP-1 have the potential to distinguish QFS and CFS patients from HC.

Source: Raijmakers RPH, Roerink ME, Jansen AFM, Keijmel SP, Gacesa R, Li Y, Joosten LAB, van der Meer JWM, Netea MG, Bleeker-Rovers CP, Xu CJ. Multi-omics examination of Q fever fatigue syndrome identifies similarities with chronic fatigue syndrome. J Transl Med. 2020 Nov 26;18(1):448. doi: 10.1186/s12967-020-02585-5. PMID: 33243243. https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-020-02585-5  (Full text)

Objective Cognitive Performance and Subjective Complaints in Patients With Chronic Q Fever or Q Fever Fatigue Syndrome

Abstract:

Background: Primary aim of this study was to compare cognitive performance of patients with chronic Q fever or Q fever fatigue syndrome (QFS) to matched controls from the general population, while taking performance validity into account. Second, we investigated whether objective cognitive performance was related to subjective cognitive complaints or psychological wellbeing.

Methods: Cognitive functioning was assessed with a neuropsychological test battery measuring the domains of processing speed, episodic memory, working memory and executive functioning. Tests for performance validity and premorbid intelligence were also included. Validated questionnaires were administered to assess self-reported fatigue, depressive symptoms and cognitive complaints.

Results: In total, 30 patients with chronic Q fever, 32 with QFS and 35 controls were included. A high percentage of chronic Q fever patients showed poor performance validity (38%) compared to controls (14%, p = 0.066). After exclusion of participants showing poor performance validity, no significant differences between patients and controls were found in the cognitive domains. QFS patients reported a high level of cognitive complaints compared to controls (41.2 vs 30.4, p = 0.023). Cognitive complaints were not significantly related to cognitive performance in any of the domains for this patient group.

Conclusions: The high level of self-reported cognitive complaints in QFS patients does not indicate cognitive impairment. A large proportion of the chronic Q fever patients showed suboptimal mental effort during neuropsychological assessment. More research into the underlying explanations is needed. Our findings stress the importance of assessing cognitive functioning by neuropsychological examination including performance validity, rather than only measuring subjective cognitive complaints.

Source: Reukers DFM, Aaronson J, van Loenhout JAF, et al. Objective cognitive performance and subjective complaints in patients with chronic Q fever or Q fever fatigue syndrome. BMC Infect Dis. 2020;20(1):397. Published 2020 Jun 5. doi:10.1186/s12879-020-05118-z https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7275429/ (Full text)