Sinusitis and its Management

The paranasal sinuses refer to the frontal, maxillary, sphenoidal and ethmoidal sinuses. These develop as diverticula from the nasal mucosa and are rudimentary or absent at birth, only expanding rapidly during the eruption of permanent teeth and again at puberty.¹

It is useful to know that they may cause diagnostic difficulties due to referred pain: the maxillary sinus is innervated by the infraorbital nerve and anterior, middle and posterior superior alveolar nerves. Hence pathology here may be felt as upper jaw pain, toothache or pain in the skin of the cheek.²

This is an inflammation of the membranous lining of one or more of the sinuses. Sinusitis may also be referred to as rhinosinusitis because inflammation of the nasal mucosa generally precedes and accompanies sinusitis. It can occur as a result of a variety causes of inflammation, the pathophysiology being that this leads to sinus cavity obstruction and subsequent infection (acute sinusitis) and chronic inflammation (chronic disease). Sinusitis is temporally classified as:⁴

• Acute: this is an infection lasting 7-30 days.
• Subacute: the inflammation lasts 4-12 weeks.
• Recurring: there are >3 significant acute episodes in a year lasting ≥10 days with no intervening symptoms.
• Chronic: symptoms persist for >90 days (these may be caused by irreversible changes in the mucosal lining of the sinuses), with or without acute exacerbations.

Viral disease is said to last less than 10 days whereas worsening symptoms after 5 days or symptoms extending beyond 10 days suggest bacterial infection.

• Upper respiratory tract infection
• Allergy
• Asthma
• Smoking
• Hormonal status (e.g. pregnancy)
• Nasal dryness
• Diabetes mellitus
• Presence of a foreign body
• Inhalation of irritants (e.g. cocaine)
• Iatrogenic (e.g. nasogastric tubes, mechanical ventilation)
• Dental problems (e.g. trauma, infection)
• Some sporting activities (e.g. swimming, diving, high altitude climbing)
• Mechanical obstruction (e.g. normal anatomical variations, nasal polyps)
• Previous history of trauma (nose, cheeks)
• Immunocompromise

Rare causes include cystic fibrosis, neoplasia, as a part of Samter's triad (aspirin sensitivity, rhinitis, asthma), sarcoidosis, Wegener's granulomatosis and immotile cilia syndrome. Sinus surgery can also predispose individuals.

There is some controversy as to whether this diagnosis can be made in young children who have very poorly developed sinuses - radiographic evidence of sinuses is only visible from about 9 years of age. Current consensus is that it can occur in children over the age of one. Symptoms may vary a little from those of adults and can include: irritability, lethargy, snoring, mouth breathing, feeding difficulty and hyponasal speech.

In general practice, the most helpful examination technique is simple palpation as this is quick and easy to perform. Percussion and transillumination are also described although these are not reliable³ and a diagnosis should not rest on these alone. Examination of the sinuses should be complemented by a simple assessment of the nose (external and speculum exam) to assess for evidence of related pathology. Thereafter, investigations are guided by clinical suspicion.

Palpation

All but the sphenoidal sinuses can be palpated for tenderness:

• Frontal sinus - press upward beneath the medial side of the supraorbital ridge.
• Maxillary sinus - press against the anterior wall, below the inferior orbital margin.
• Ethmoidal sinus - press medially against the medial wall of the orbit.

Percussion

Theoretically, sinuses can be percussed for evidence of dullness but the area to percuss is small and their sizes vary from one individual to another. This examination method does elicit tenderness where there is infection.⁵

Transillumination⁶

This technique requires a darkened room and a torch equipped with a sheath which can be drawn up around the light source. It is used to visualize the frontal and maxillary sinuses:

• Frontal sinus - draw the sheath up around the light source so that light is only emitted from the tip. This is placed under the medial orbital roof, just posterior to the rim. Direct superomedially and press gently so that no light leaks into the room. Look for a reddish glow just above the eyebrow.
• Maxillary sinus - pull the sheath back so that light is transmitted circumferentially from the end of the torch. The torch is placed in the patient's mouth with the instruction to seal the lips around the torch but to leave the jaw open. Direct the light superiorly and look for a red glow in the malar areas.

This tends to arise as a result of a viral infection and a diagnosis of acute sinusitis is made if there is sinus drainage obstruction and subsequent secondary bacterial infection.This is most commonly caused by Strep. pneumoniae, H. influenzae and M. catarrhalis⁷ the latter being more common in children.⁵ Approximately 90% of patients who have viral upper respiratory tract infections have some degree of sinus involvement but only ~ 5% of these patients subsequently develop bacterial superinfection amounting to acute sinusitis.¹ Other causes of mucosal swelling (such as allergy) may also lead to impairment of sinus mucus clearance and subsequent acute sinusitis.⁶

Epidemiology

This is a very common condition affecting about 1 in 10 people at some point in their lives. A UK general practice can expect to see about 250 cases of acute sinusitis per 10,000 person-years.³

Symptoms

Most commonly, patients present with a non-resolving cold (> 1 week or worsening symptoms over 4-5 days) which may have a biphasic character: the initial viral infection which appears to begin settling is followed by further malaise relating to the bacterial sinusitis. There may be pain over the affected sinus (this is neither sensitive nor specific⁷ and is often described as 'pressure' by the patient), pyrexia, purulent nasal discharge ± decreased or absent smell. A poor response to nasal decongestants can be suggestive and in the intensive care setting, this diagnosis should be considered in pyrexia of unknown origin.¹

Signs

There may be little to elicit other than pain on palpation of the sinuses. Erythema and oedema of the nasal mucosa may also be found.

Diagnosis³

Acute sinusitis is diagnosed if there are two major features or one major feature and two minor features of:
Major features

• Facial discomfort (e.g. a feeling of congestion or fullness, often unilateral and worse when bending forwards)
• Nasal obstruction
• Purulent nasal discharge or postnasal drip
• Decreased or absent sense of smell
• Fever

• Headache
• Halitosis
• Fatigue
• Dental pain
• Cough
• A feeling of pressure or fullness in the ears

Investigations

Diagnosis is made on the above criteria. There is some controversy about carrying out further investigations which can be done (e.g. ESR, CRP, plain x ray films, ultrasonography, CT imaging and sinus puncture⁴) but have not always been proven to be helpful and which are not generally available in primary care anyway.³ Sinus puncture may have a role in a secondary care setting where there is a pressing need for organism identification.

Differential diagnosis

• Allergic rhinitis
• Common cold
• Adenoiditis, particularly in children
• There are also a number of causes of headaches

Management

• Most cases can be managed in the primary care setting.
  

  Referral criteria4 Unilateral signs (e.g. mass) Bleeding Suspicion of spread to orbit - see orbital cellulitis article Maxillary paraesthesia Suspicion of intracranial spread Immunocompromised patient

• Antibiotics are reserved for severe or prolonged infections (>5 days):³ only 30% to 40% of patients with clinically suspected sinusitis actually have a bacterial infection.
• Advise analgesia as required.⁴ Topical nasal decongestants can help as can warm facial packs applied to the slightly elevated head but steam inhalations and nasal douches are not recommended.³ Suggest a review if the symptoms worsen or do not resolve within 7 days. There is debate regarding use of topical steroid sprays but these are not generally thought to be useful.^8,9
• If a decision is made to use antibiotics, amoxicillin is a good first line (with doxycycline, azithromycin and clarithromycin being the recommended treatments for patients with true penicillin sensitivity).³
• Offer review in 7 days for patients not treated with antibiotics and 72 hours in those treated with antibiotics.
• If response to antibiotics is poor, consider compliance issues, look for complications and consider a second-line antibiotic (co-amoxiclav or one of the three suggested above in the penicillin-sensitive patient).³
• Refer if there is still no response or if the patient is deteriorating. Management may involve microbiological investigation and surgery may be required in recalcitrant cases where infection is severe and sinus washout is indicated. Endoscopic approaches have largely replaced open surgery and involves restoring sinus ventilation and mucociliary function. Post-operative care will be directed by the team but is likely to involve intranasal steroids, saline douching and careful nasal toileting.⁴
• Management principles for children are the same but doxycycline is contraindicated. Pregnant or breast-feeding mothers in whom antibiotics are considered vital should be treated with erythromycin.³

Complications⁷

These are rare (of the order of 1 in 10,000 cases of sinusitis³) and occur more commonly in children. They include orbital cellulitis, meningitis, brain abscess, osteomyelitis (known as Pott's Puffy Tumour when the frontal bone is affected) and cavernous sinus thrombosis. Very occasionally, there is formation of a cutaneous fistula. Acute sinusitis can become chronic.

Prognosis

Symptoms are likely to be relatively slow to resolve (2-3 weeks, regardless of whether antibiotics are taken or not) but over two thirds of patients experience improvement or resolution of symptoms without antibiotic treatment.⁹

This is more frequently caused by anaerobes, Gram-negative bacteria and S.aureus.⁴ Patients suffering from chronic sinusitis are more likely to have a chronic underlying problem (see risk factors above) and patients with this diagnosis should be actively investigated to rule out any treatable conditions.

Epidemiology

Although this is less common than acute sinusitis, it remains a reasonably common entity in itself, accounting for about 25 cases per 10,000 person years in an average UK GP practice.³ There is a reported increasing prevalence in all age-groups, the reason for which is not quite clear.⁷

Symptoms

These are similar to those of acute sinusitis but not as florid.

Signs

A dull ache on palpation and nasal mucosal inflammation may be noted. Nasal purulence is strongly suggestive and an ear examination should be performed to rule out middle ear fluid.¹⁰ In older patients, it is prudent to complement this with a full neurological examination as some neurological disorders can be associated with chronic sinusitis.

Diagnosis

The diagnostic major and minor features are the same as for acute sinusitis but criteria stipulate ≥2 major factors or one major and two minor factors or nasal purulence on examination for ≥12 weeks.⁶

Investigations

Diagnosis may need to be confirmed with further investigations such as those outlined for acute disease but the same limitations apply.

Differential diagnosis¹⁰

• Rhinitis (allergic or non-allergic)
• Foreign bodies in the airways
• Fungal sinusitis
• Cystic fibrosis
• Tumours (e.g. nasopharyngeal, tumours of the sinus or of the nasal cavity, skull base)
• Turbinate dysfunction
• Juvenile nasopharyngeal angiofibroma

Management (recurring and chronic sinusitis)^3,4

• Management of these patients in primary care can be tricky and there is no clear published data regarding the optimal treatment in this setting.
• Actively ask about predisposing conditions and manage these accordingly. If there is no improvement, referral is appropriate.
• Worrying features outlined in the box above (see acute sinusitis) should also prompt referral.
• Management revolves around topical nasal steroids which tends to be long term (>3 months).
• Refractory cases or patients with concurrent allergies may benefit from a course of oral steroids with the usual precautions taken in at-risk groups (e.g. diabetics, those with gastric ulceration, psychiatric patients etc).
• There is no clear evidence supporting the use of long-term antibiotics and an ENT opinion is recommended before these are started in primary care.
• Management principles are the same in children but have a lower threshold for referring. Bear in mind that this condition is relatively rare in children and consider alternative diagnoses (e.g. rhinitis or adenoidal disease).

Complications

Acute exacerbations are associated with the same rare complications as those outlined above for acute sinusitis. Additionally, these patients may experience the psychological problems associated with chronic pain and ill health. Pain may be particularly bad when travelling by plane, especially on landing. Furthermore, scuba-divers should consult with specialists as their sinuses are more prone to barotrauma.

Prognosis

By its nature, this is a long-term problem which does not lend itself to rapid cure. However, optimal management of underlying causes as well as appropriate referral can result in a good outcome and a patient free of symptoms.

This is an uncommon infection that was traditionally associated with immunocompromise but which is increasingly seen among the immunocompetent patient population. It is also associated with diabetes. The most common culprits are the Aspergillus and Mucor species. These give rise to two distinct clinical pictures:

• Non-invasive fungal sinusitis: this usually manifests itself with a chronic sinusitis picture before the correct diagnosis is made. It may be further classified into allergic fungal sinusitis and sinus mycetoma - a unilateral lesion usually involving the maxillary sinus.
• Invasive fungal sinusitis: this may take on an acute, fulminant character when it is associated with a high mortality rate unless recognised and treated early, or a more slowly invading nature which tends to occur in diabetics. A chronic granulomatous type is also described (almost exclusively) in immunocompetent North African patients.

Symptoms and signs

• Allergic fungal sinusitis - symptoms of chronic sinusitis, often associated with asthma ± nasal polyposis.There is often an atopic background. Diagnosis is difficult and may only be made after repeated investigation (± surgery) for chronic sinusitis.
• Sinus mycetoma - similar to the presentation of acute sinusitis. These (immunocompetent) patients may complain of blowing gravel-like material from the nose.
• Acute invasive fungal sinusitis - patients are severely ill with fever, cough, nasal discharge, headache and mental status changes (there is a rapid spread to the orbit and the CNS). Orbital cellulitis may be evident. Dark ulcers may be seen on examination of the septum, the turbinates or the palate. Late on, there may be evidence of a cavernous sinus thrombosis.
• Chronic invasive fungal sinusitis - similar to chronic sinusitis - patients are not acutely unwell but may show evidence of the orbital apex syndrome (optic neuropathy and restricted globe movements).
• Granulomatous invasive fungal sinusitis - similar to chronic invasive sinusitis but with more apparent orbital features.

Diagnosis

This is usually made following referral to the ENT department. Serum total fungus-specific IgE concentrations may be elevated in patients with allergic fungal sinusitis and CT imaging will further help diagnosis. MRI imaging helps outline any CNS spread. Microbiology and histology provide the final diagnosis.

Management

This should be under the care of the ENT team. The mainstay of treatment is surgical, the aim being to debride the infected tissue (this ranges from conservative to radical, depending on the type of fungal sinusitis). Antifungal treatment is used where there is invasive infection. Systemic steroids may be indicated post-operatively in patients with allergic fungal sinusitis.

Complications

Varying degrees of invasion and tissue erosion eventually occur in all types if left untreated.

Prognosis

All but the acute invasive form carry a good prognosis once the diagnosis is made and treatment completed. Fulminant fungal sinusitis is associated with a 50% mortality rate, even with aggressive surgical and medical treatment. Relapses are common during subsequent episodes of neutropenia so treatment with systemic antifungals as prophylaxis is indicated where this occurs.

Barotrauma of the paranasal sinuses is a risk factor for anyone exposed to ambient pressure changes. These pressure changes most often result from travel through mountainous regions, flying, or diving. The problem arises as a result of the small size of the ostia of the sinuses so limiting the exchange of gases and mucus. This may lead to accumulation of secretions and an acute or chronic sinusitis. It is a relatively rare condition most often affecting the frontal sinuses.

Symptoms and signs

Mild inflammation may give rise to pain (particularly on returning to starting conditions, e.g. back to sea level), congestion and occasional epistaxis. More severe inflammation is characterised by severe, sharp pain and a pressure sensation which is typically in the forehead, in the mid-face or retro-orbital. Epistaxis is common. Clinical examination and findings are similar to those in acute sinusitis.

Diagnosis

This is generally made on history and examination - further investigations add little although changes may be seen on CT imaging. Differentials are as for acute and chronic sinusitis.

Management

Treatment is best carried out as soon as the symptoms occur although this is not always possible. Ideally, a patient should return to the altitude at which symptoms occurred. Management involves oral analgesia, nasal decongestants to establish ventilation of the sinuses and a prophylactic course of antibiotics (see antibiotic treatment in acute sinusitis).

Complications

See those of acute sinusitis, above. These are rare.

Prognosis

Patients should make a full recovery from an acute episode although repeated barosinusitis can lead to chronic sinusitis.