The evidence base for first-line management of acute sinusitis is poor, and is largely derived from expert opinion and the historical use of self-care measures and symptomatic treatment.

Prognosis and advice on antibiotics

The National Institute for Health and Clinical Excellence estimate that the average duration of acute sinusitis is 2.5 weeks [NICE, 2008a]. A systematic review analysed the placebo arms of several randomized controlled trials (RCTs), and found that, after 7–15 days, 73% of people taking placebos experienced some improvement in their symptoms, and 30% had complete recovery [Rosenfeld et al, 2007].

Current UK policy aims to decrease unnecessary antibiotic prescribing: informing the person of the limited benefit of antibiotics, together with the real risk of adverse effects, may encourage this [NICE, 2008a].

Analgesia

The effectiveness of paracetamol or ibuprofen in the symptomatic relief of the common cold and influenza has been confirmed by RCTs [Eccles, 2006]. It is reasonable to extrapolate these data to the management of sinusitis, which has similar symptoms and causative pathogens [ICSI, 2008].

Intranasal decongestants

Intranasal decongestants are thought to promote mucociliary clearance and sinus drainage, and may be of benefit in people with nasal congestion [Fokkens et al, 2007]. However, evidence from RCTs to support their use is conflicting.

It is important that nasal decongestants are not used for more than 7 days, as prolonged use is associated with rebound nasal congestion when treatment is stopped. This encourages continued use, which can result in hypertrophy of the nasal mucosa (rhinitis medicamentosa) [BNF 56, 2008].

Although oral decongestants have been found to be of some benefit in relieving nasal congestion associated with the common cold [Taverner and Latte, 2007], there is a lack of evidence for their effectiveness in sinusitis [Fokkens et al, 2007], and they may cause systemic adverse effects or interact with other drugs [BNF 56, 2008].

Rest and increased fluid intake

Adequate rest is recommended by experts if the person feels fatigued during the course of the infection. However, in general, the benefits of rest have not been investigated by controlled studies.

There is very little evidence to support increased fluid intake in acute sinusitis. A Cochrane review (search date: July 2005) investigated this intervention but found no controlled trials suitable for inclusion [Guppy et al, 2005]. Nevertheless, it is important to keep the body hydrated at all times, and as fluid loss is likely to be greater when fever and nasal discharge are present, it is prudent to drink more fluid than normal.

Measures for symptomatic relief

Self-care measures are consistent with recommendations made by the Institute for Clinical Systems Improvement [ICSI, 2008], as they are not usually suitable for investigation by RCTs; instead they are based on consensus statements and medical opinion, according to physiological principles.

Irrigation of the nose with saline solution has been found to be of benefit in the treatment of chronic sinusitis by a Cochrane review [Harvey et al, 2007]. However, it may also give symptomatic relief of nasal congestion in acute sinusitis [ICSI, 2008].

Face packs may promote drainage of mucus and provide localized symptomatic relief, although the evidence for this is anecdotal [ICSI, 2008].

Steam inhalation has been found to be effective for the symptomatic treatment of the common cold [Singh, 2006], although trial data for acute sinusitis are lacking. It is not generally recommended due to concerns about the risk of scalding, or direct steam burns, especially when used in children. If used, the recommended technique is to sit in the bathroom with a hot shower running. The use of boiling kettles or bowls of hot water should always be avoided [Murphy et al, 2004].

Complementary and Alternative Medicine (CAM)

CKS found insufficient evidence to recommend CAM for acute sinusitis, owing to the limited number and quality of controlled trials for these interventions. Potential harms of CAM should also be considered before they are tried.

A review of complementary therapies found no convincing evidence for the use of dietary supplements, bromelain (pineapple extract), zinc, or vitamin C for the treatment of sinusitis. Some studies have reported evidence for the effectiveness of Echinacea in the treatment of upper respiratory tract infections, but these have generally been small and of poor quality [Asher et al, 2001].

A systematic review (search date: October 2005) identified a total of 10 RCTs that investigated the effectiveness of herbal medicines for acute and chronic sinusitis. The authors concluded that the evidence of benefit for these interventions was limited, but there was some encouraging evidence to support the use of Sinupret^® and bromelain, specifically in acute sinusitis [Guo et al, 2006].

Intranasal corticosteroids, antihistamines, and mucolytics

Although there is some evidence from RCTs that intranasal corticosteroids are effective for acute sinusitis, they are not routinely recommended, as the clinical benefits are small and take several days to develop (most trials assessed outcomes after 2–3 weeks) [Zalmanovici and Yaphe, 2007].

Oral corticosteroids have been found to improve symptoms of pain in two RCTs [Fokkens et al, 2007], but are not recommended because of the risk of systemic adverse effects.

Antihistamines are not recommended unless the person has a coexisting allergic disorder, such as allergic rhinitis. Although one RCT suggested that loratadine may be of benefit for repeat exacerbations of sinusitis, the results from this trial are difficult to interpret as both groups also received both oral prednisolone and co-amoxiclav [Braun et al, 1997].

There is no convincing evidence that mucolytics are of benefit for acute sinusitis. One trial compared two mucolytics with each other (neither are available in the UK), but without a placebo comparator the results are difficult to interpret [Garrubba and Smussi, 1988].

These recommendations are largely based on expert opinion according to known disease progression and bacterial sensitivities to antibiotics.

Identifying people to treat with antibiotics

Recommendations for the prescribing of antibiotics for acute sinusitis are based on the clinical guideline Respiratory tract infections — antibiotic prescribing, published by the National Institute for Health and Clinical Excellence (NICE) [NICE, 2008a]. This can be downloaded from www.nice.org.uk (pdf).

The NICE Guideline Development Group stated that, due to a lack of published evidence, it is not possible to identify subgroups of people who require immediate treatment with antibiotics, but they do list groups of people for whom no treatment or delayed treatment is unsuitable. For these people, immediate antibiotics 'and/or further appropriate investigation and management' is necessary. CKS infers from this that:

People with serious systemic infection, or intra-orbital or intracranial complications, should be admitted to hospital immediately.

For people who are systemically unwell but are in not in immediate danger of complications, an immediate antibiotic prescription should be considered.

Antibiotics are recommended in people who have serious comorbidities, or other combinations of risk factors, as these people are more likely to develop complications.

Delayed prescribing strategy

There is some evidence from randomized controlled trials (RCTs) for other upper respiratory tract infections that delayed prescriptions can significantly reduce the amount of antibiotics taken, without adversely affecting other outcomes such as patient satisfaction.

Although NICE did not identify any studies specifically on delayed prescribing in sinusitis, the Guideline Development Group reached a consensus opinion that sinusitis should be treated in the same way as for the other upper respiratory conditions (acute otitis media, pharyngitis, bronchitis, and common cold).

NICE do not offer clear guidance on who should be offered delayed treatment, but CKS believes profuse purulent discharge and severe facial pain are likely to be at least partly selective for bacterial infection, and warrant consideration for this strategy [Klossek and Federspil, 2005]. There is evidence from RCTs that antibiotics are twice as likely to benefit people with purulent discharge compared with those without this symptom.

Antibiotic effectiveness and harms

There is some evidence from RCTs that antibiotics are of limited benefit in the treatment of sinusitis, with between 7 and 14 people requiring treatment for one person to benefit (NNT 7–14), depending mainly on the initial accuracy of diagnosis.

There is similar evidence of antibiotic effectiveness in the treatment of children.

However, there is some evidence that the likelihood of harms occurring due to adverse effects is in a similar range.

Antibiotic selection

There is no evidence from RCTs to support the use of one antibiotic over another. In the absence of trial data, antibiotic selection should be made with respect to local resistance patterns, with consideration given to practical issues such as convenience of the regimen, adverse effects, and cost.

Amoxicillin is usually considered as the first-line antibiotic because it has the most clinical data associated with it, having been used extensively as the comparator drug in many RCTs, and it has good activity against the pathogens most commonly implicated in bacterial sinusitis, Streptococcus pneumoniae and Haemophilus influenzae [Klossek and Federspil, 2005]. In addition, it is well tolerated by most people and is inexpensive.

A high dose of amoxicillin is recommended because antibiotics are only recommended for consideration for people with very severe symptoms, a high dose has most chance of success if the causative pathogen is bacterial, and a high dose may also overcome low-level beta-lactamase resistance, also increasing the chance of success if the pathogen is bacterial [Livermore, Personal Communication, 2010].

Doxycycline, erythromycin, or clarithromycin are recommended if there is a known history of allergy to penicillin.

Doxycycline is active against both S. pneumoniae and Haemophilus influenzae [Chopra, 2003]. It is available as a convenient, once-daily regimen (after an initial loading dose), is well tolerated by most people, and is relatively inexpensive.

Erythromycin and clarithromycin are active against most of the bacterial pathogens involved in sinusitis [Bryskier and Butzler, 2003], although resistance to them is increasing, especially in H. influenzae.

Erythromycin is the preferred choice in pregnant women as there is extensive experience of its use in pregnancy. Paediatric formulations of erythromycin are also less expensive than clarithromycin [BNF 56, 2008].

Clarithromycin is generally thought to be better tolerated than erythromycin [Aronson, 2006], and also has a more convenient dosing regimen [DTB, 1991].

Antibiotic duration and dose

CKS recommends a 7-day course of high-dose antibiotics for most people:

There is evidence from RCTs that suggests shorter courses of antibiotics (typically 5 days) are probably as effective as longer courses (typically 10 days).

A 7-day course is a reasonable choice, especially as many antibiotics come in pack sizes that last for a week (this may encourage compliance and reduce wastage), and it has also been suggested that courses lasting for longer than 1 week are less likely to be completed [Elies and Huber, 2004].

Higher doses of antibiotics are recommended (where applicable, such as amoxicillin) because these are appropriate for 'severe' infections [BNF 56, 2008], and less severe infections should not usually be treated.

First-line treatment

CKS recommends the use of antibiotics to treat acute sinusitis if symptoms persist for more than 7 days, or if the person is deteriorating, as evidence suggests this increases the likelihood of bacterial involvement, and antibiotics are more likely to be effective. This is accordance with narrative guidelines [Hickner et al, 2001; Klossek and Federspil, 2005].

First-line antibiotics (amoxicillin, doxycycline, erythromycin, or clarithromycin) are appropriate in this situation.

Second-line treatment

Co-amoxiclav is usually recommended as second-line treatment in people who are not allergic to penicillin because it is effective against the bacteria implicated in sinusitis, including Moraxella catarrhalis and penicillin-resistant strains of Streptococcus pneumoniae, and is probably as effective as other antibiotics that are beta-lactamase resistant (for example, third-generation cephalosporins) [Karageorgopoulos et al, 2008].

Azithromycin is a suitable choice if another macrolide was unsuccessful because of treatment failure or compliance issues (such as gastrointestinal adverse effects). It has greater activity against Haemophilus influenzae than erythromycin (which has poor activity [DTB, 1995]), it causes less gastrointestinal effects than erythromycin [DTB, 1991], and compliance is less of an issue as it is taken over the course of 3 days rather than a week.

Referral recommendations are based on expert opinion and are consistent with a UK guideline [Scadding et al, 2007] and a narrative review on the management of sinusitis [Ah-See and Evans, 2007].

The most important concern with sinusitis is the development of a complication, which can lead to blindness or even death. Complications are estimated to occur with a frequency of 1 in 10,000 cases of sinusitis [Balk et al, 2001].

Options available in secondary care include:

Administration of intravenous antibiotics.

Sinus puncture and irrigation, which allows a sample of sinus fluid to be taken for bacterial culture, and may provide some symptomatic relief [Blomgren et al, 2005]. However, this procedure is no longer commonly performed, has a poor diagnostic yield, and carries the risk of secondary contamination.

Surgery may be indicated for severe acute sinusitis, but is more commonly used for chronic sinusitis that is refractory to medical treatment. Surgery is increasingly performed using endoscopic techniques [Evans, 1998].

Recommendations for the assessment of sinusitis are derived from a UK guideline [Scadding et al, 2007] and a European guideline [Fokkens et al, 2007].

Nasal polyps commonly coexist with chronic sinusitis, especially in people with asthma (7–14% are estimated to have polyps) or hypersensitivity to nonsteroidal anti-inflammatory drugs (36–60% have polyps). The presence of nasal polyps may require referral for surgery.

Risk factors for chronic sinusitis:

Atopic disorders are known to coexist or be risk factors for chronic sinusitis, and require separate management [Smart and Slavin, 2005]. For more information, see the CKS topics on Allergic rhinitis and Asthma.

The suspected presence of immunosuppression should prompt referral or the seeking of expert advice.

Dental infection is estimated to be associated with 5–10% of cases of chronic sinusitis and requires assessment by a dentist or otolaryngologist [Gwaltney, 1995].

Recommendations for information and advice are largely based on expert opinion and observational studies, rather than controlled trials. Treatment recommendations are consistent with the European position paper on rhinosinusitis and nasal polyps [Fokkens et al, 2007], and reflect historical UK practice for the treatment of chronic sinusitis.

Prognosis

The natural course of chronic sinusitis is poorly documented, but persistent symptoms are likely to last months or longer without appropriate management (intranasal corticosteroids or referral for secondary care options). However, it is widely believed that good control of predisposing factors, such as allergic rhinitis and asthma, will benefit sinusitis symptoms [Blomgren et al, 2005].

Dental hygiene, smoking, and diving

Dental infection is associated with chronic sinusitis in about 5–10% of people [Gwaltney, 1995], so dental hygiene should be encouraged.

Although there is no strong evidence that smoking causes chronic sinusitis, there is a hypothetical risk that tobacco smoke may exacerbate chronic sinusitis symptoms, particularly in people with allergies [Benninger, 1999].

If the person is considering underwater diving, consider seeking specialist advice, as there is a risk of sinus barotrauma (tissue injury resulting from pressure differences). Potential complications of barotrauma include cerebral empyema, pneumocephalus, blindness, and cranial nerve palsies [Parell and Becker, 2000].

Self-care measures for acute episodes

Recommendations for symptomatic relief of acute symptoms are consistent with those made by the Institute for Clinical Systems Improvement [ICSI, 2008]. For further information, see Basis for management of acute sinusitis.

Intranasal corticosteroids for chronic sinusitis

In general, there is a lack of good-quality evidence on the treatment of chronic sinusitis, with relatively few placebo-controlled trials of interventions on which to base recommendations.

Intranasal corticosteroids are recommended by the European guideline, with the authors stating that 'nasal corticosteroid treatment represents one of the long-term treatment modalities in patients with chronic sinus disease' [Fokkens et al, 2007].

The anti-inflammatory properties of corticosteroids are well documented in other conditions, and they have been used historically to treat chronic sinusitis. There is also evidence from placebo-controlled trials to support the use of intranasal corticosteroids in people with chronic sinusitis both with and without co-existing nasal polyps.

Intranasal corticosteroids are likely to be well tolerated, with minimal adverse effects even after prolonged use. Inhaled corticosteroids, used by many people with asthma, are more likely to cause systemic adverse effects than intranasal corticosteroids [Fokkens et al, 2007].

Prolonged use of antibiotics

The evidence for prolonged use of antibiotics is lacking because of an absence of placebo-controlled trials.

Open-label studies have indicated that low-dose macrolides may have cure rates of 60–80% in people who are refractory to surgery, but this needs to be confirmed by further studies [Scadding et al, 2007].

CKS recommends that, because of the lack of evidence of efficacy, the potential for adverse effects, and the concern of increasing bacterial resistance, specialist advice should be sought before long-term antibiotics are initiated.

Referral recommendations are based on expert opinion and are consistent with a UK guideline [Scadding et al, 2007] and a narrative review on the management of sinusitis [Ah-See and Evans, 2007].

Routine referral is recommended if a trial of intranasal corticosteroids has not proved adequately effective, as this effectively represents maximal treatment in primary care. There are also limited treatment options for unremitting facial pain or frequent, severe, acute episodes of sinusitis in primary care.

Options that are available in secondary care include:

Endoscopic surgery to drain sinuses and restore normal mucociliary function [Khalil and Nunez, 2006].

Removal of nasal polyps.

Surgery to correct nasal septum deviation and other nasal abnormalities (such as turbinate diathermy or reduction).

Initiation of other drug treatments (such as antibiotics or anti-leukotrienes) or aspirin desensitization (although this is rarely practised in the UK).