Tipos de errores detectados y tipos de

increased fa gue levels a er acute Q-fever [67]. Although some found that gender was not a predictor [12], others found an overrepresenta on of women in high severity groups for

fa gue, mood disturbance and neurocogni ve diffi cul es [60]. Being female or a young adult,

and smoking were characteris cs signifi cantly associated with long-term reduced health status including fa gue [62, 67]. In contrast, another study found no associa on between fa gue and age [59].

In conclusion, neither psychological nor microbial factors seem to predict post-infec ve fa gue, including QFS.

Severity of the acute illness. It was stated that one of the key risk factors for the develop- ment of post-infec ve fa gue, including QFS pa ents, is the severity of the acute illness [12]. Pa ents with post-infec ve fa gue had a longer mean dura on of the acute illness, and more days in bed and days out of role during the acute phase compared to controls [18].The clinical expression of acute Q-fever seemed an essen al factor in the subsequent sustained decrease in health status [58], which is supported by the fi nding that QFS usually follows acute Q-fever and rarely if ever asymptoma c infec on [70]. Pre-exis ng health problems [62, 67], and hospitalisa on, as an indicator of the severity of the ini al infec on, were also fa gue predic- tors [59, 62]. No symptoms during the acute Q-fever infec on were predictors for persis ng symptoms [3], nor did these determine the long-term health status [65]. Neither IL-6 and CRP levels nor an bio c treatment during the acute infec on were predictors for the develop- ment of prolonged fa gue [3, 63]. No rela onship was found between fa gue and an body

tres six years a er the Q-fever infec on [49].

In conclusion, the severity of the acute Q-fever infec on seems a key factor for worse long-term health status, including fa gue and QFS.

Gene c factors in predic ng fa gue. A single nucleo de polymorphism (SNP) of the T allele IFNy+874T/A appeared to be the best predictor of increased fa gue a er the acute phase of several infec ons, including C. burne i [60]. While the C allele of IL-10-592C/A SNP

exerted a protec ve eff ect on neurocogni ve diffi cul es, the A allele IL-10-592 SNP and G

allele IL-6-174G/C SNP were associated with increased mood disturbance [60].

In conclusion, as evidence is scarce, more research is needed regarding gene c factors predic ng fa gue in QFS.

Preven on/therapy

Eleven ar cles contained informa on on preven on/therapy of which six are classifi ed in the main table preven on/therapy (S5 Table) [5, 6, 39-42].

Preven on. No ar cles on the preven on of QFS were found. The Dutch guideline on

QFS proposes to advice pa ents within the fi rst six months a er acute Q-fever or a er estab- lished QFS to: i) stay mentally and physically as ac ve as possible, adjust pace if necessary;

188 | Chapter 9

ii) alternate ac vi es, also within ac vi es; iii) keep fulfi lling the role in daily life; iv) maintain a regular sleep-wake pa ern; v) avoid focusing on fa gue; and vi) focus on feasible ac vi-

es and appreciate accomplishments [17]. It is also proposed to explain that most pa ents recover within the fi rst 6-12 months following acute Q-fever.

An bio c treatment. Four ar cles reported on the eff ect of long-term an bio c treat-

ment in assumed QFS pa ents [5, 6, 39, 40]. No randomised controlled trial (RCT) was found. Treatment with either 3 months of minocycline 200mg/day (n=18), levofl oxacine 200mg/day (n=1), or erythromycin 400mg/day (n=1), improved performance status and reduced fa gue [6], concluding that minocycline was useful in trea ng QFS [6]. In a pilot-study, treatment with three months of minocycline 100mg/day (n=29), doxycycline 100mg/day (n=26), or levofl oxacin 200mg/day (n=3), showed improvement in performance status, headache, and mean weekly temperature [39]. A case-series (n=3) [5] and case-report (n=1) [40] showed inconsistent results of treatment with long-term an bio cs. According to others, the posi ve

eff ect of an bio c treatment for QFS is not confi rmed nor advised [17]. The effi cacy of long-

term an bio c treatment is now tested in a RCT but results are not yet available [42]. In conclusion, available data on long-term an bio c treatment for QFS are scarce and inconsistent.

Cogni ve behavioural therapy (CBT) and graded exercise therapy (GET). CBT proved

eff ec ve in reducing symptoms and improving func oning in CFS pa ents [74, 75], and in chronic fa gue in chronic illnesses [76-78]. It was suggested as treatment op on for QFS pa ents who experience psychological distress [61]. Based on CFS literature and similari es between CFS and QFS, CBT is advised in the Dutch QFS guideline, although suspected not to be benefi cial for all pa ents [17]. The eff ec veness of CBT treatment for QFS is currently under inves ga on [42]. Also GET is recommended for QFS pa ents, as proven eff ec ve in reducing fa gue in CFS [17].

In conclusion, although evidence is lacking, CBT and GET might be eff ec ve in reducing fa gue in QFS pa ents.

Treatment of QFS-related symptoms. Three ar cles (all n=1) reported treatment of

QFS-related symptoms [28-30]. The authors concluded that educa on and counselling about QFS and QFS-related symptoms should be provided to QFS pa ents [28]. A en on to the pa ent’s mental state is necessary in order to recognise accompanying symptoms, e.g. depressive thoughts, that should be treated [30], and involving a psychiatrist early ought to be considered [29]. This has been recognised before, where tricyclic an depressants were benefi cial treatment of mental problems a er acute Q-fever [44].

In conclusion, educa on and counselling of pa ents about QFS and QFS-related symp- toms seems important, as well as considering a pa ent’s mental state.

Alterna ve treatment. Alterna ve therapies for QFS pa ents were described (both n=1),

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