Epidemology and Diagnosis of Sinusitis

EPIDEMIOLOGY






Epidemiology of Bacterial Sinusitis:

• Viral bacterial sinusitis develops in 90% of patients with a viral upper respiratory tract infection (“cold”).
• Bacterial sinusitis has a seasonal pattern, associated with “cold” epidemics that occur in the autumn, winter, and spring, and are less common during the summer. Typically, rhinoviruses occur in early autumn and late spring, while respiratory syncytial virus, influenza virus, and coronavirus strike in early spring and winter.
• Acute bacterial sinusitis occurs in 0.5% to 2% of individuals with viral infections (colds) (about 20 million Americans yearly).
• The economic impact of rhinosinusitis is considerable.




Viral upper respiratory infection can lead to acute bacterial infection (where aerobes predominate) ultimately to chronic one (where anaerobes predominate).



DIAGNOSIS AND SIGNS AND SYMPTOMS 

Bacterial sinusitis can be classified chronologically into 5 categories:

Acute: 10 days to 4 weeks
Recurrent acute: 4 episodes of acute per year
Subacute: 4–12 weeks
Chronic: > 12 weeks
Acute exacerbation of chronic: Worsening infection, returning to chronic baseline




Definitions of bacterial sinusitis
Definitions of bacterial sinusitis
Length of infection
Acute
10 days to 4 weeks
Recurrent acute
³ 4 episodes of acute per year
Subacute
4–12 weeks
Chronic
> 12 weeks
Acute exacerbation of chronic
Worsening infection, returning to chronic baseline



Clinical Diagnosis of Bacterial Sinusitis:

Establishing a diagnosis may be difficult because differentiation must be made between allergic rhinitis and other causes of head or facial pain, asthma, and dental disorders. An allergic etiology can be confirmed by establishing a history of nasal symptoms and a history of allergy.




 Medical history, symptoms, and findings suggestive of allergy
History

Personal
Past episodes of allergy that responded to antihistamines and anti-inflammatory agents

Asthma

Skin and food allergies
Family
Allergies in close relatives
Symptoms
Itching of ears, nose, and eyes

Paroxysms of sneezing exacerbated by external factors (e.g., animal exposure, dust)
Findings
Pale, swollen, purple inferior turbinate

Evidence of atopy such as eczema, urticaria, or asthma

Allergic nasal crease


The most predictive clinical signs and symptoms of bacterial sinusitis in adults and children are pressure and pain, thick nasal discharge, fever and cough or irritability. Allergy is associated with itchy, runny nose, thin watery nasal discharge, history of seasonal allergy and other allergic symptoms.




Practical Criteria:

Practical criteria for the diagnosis of bacterial sinusitis are based on either major or minor symptoms, signs, and findings. The major ones are facial pain, congestion, nasal discharge, fever (for acute sinusitis), and purulence. Minor criteria are headache, halitosis, fatigue, dental pain, and cough. The presence of bacterial sinusitis is suspected when at least two major or one major and two minor criteria are found.


Major and minor criteria of bacterial sinusitis*
Major criteria
Minor criteria
Facial pain/pressure (requires a second major criterion to constitute a suggestive history)
Headache
Facial congestion/fullness
Fever (for subacute and chronic sinusitis)
Nasal congestion/obstruction
Halitosis
Nasal discharge/purulence/discoloured postnasal drainage
Fatigue
Hyposmia/anosmia
Dental pain
Fever (for acute sinusitis; requires a second major criterion to constitute a strong history)
Cough
Purulence on intranasal examination
Ear pain/pressure/fullness
*Diagnosis of bacterial sinusitis based on major and minor criteria. Strong history requires the presence of two major criteria or one major and two or more minor criteria. Suggestive history requires the presence of one major criterion or two or more minor criteria.




• The most common presentation in children is a persistent (and unimproved) nasal discharge or cough (or both) lasting longer than 10 days. A 10-day period separates simple viral upper respiratory tract infection (URTI) from bacterial sinusitis because most uncomplicated viral URTIs last between 5 and 7 days—by day 10 most patients are improving.




• The quality of the nasal discharge varies, and it can be thin or thick, clear mucoid, or purulent.
• Although children cough during the day, this is generally worse at night.

Enclosed are the symptoms that differentiate bacterial sinusitis from allergy:


Sinus infection versus allergy
Infection
Allergy
Nasal obstruction and/or congestion
Nasal obstruction and/or congestion
Pressure with pain
Itchy, runny nose
Thick nasal discharge
Paroxysmal sneezing
Toothache
Thin, watery nasal discharge
Fever
History of sinusitis during allergy season
Cough or irritability
Other allergic signs or symptoms



The symptoms and signs of acute bacterial sinusitis can be divided into non-severe ( rhinorrhea, cough, headache, facial pain. and low grade fever) and severe forms (Purulence, periorbital edema, and high fever). The severe form carries a higher risk of complications and mandates earlier use of antimicrobial therapy. The combination of high fever and purulent nasal discharge lasting for at least 3 to 4 days points to a bacterial infection of the sinuses.


Symptoms and signs of bacterial sinusitis
Non-severe acute sinusitis
Severe acute sinusitis
Rhinorrhea (of any quality)
Purulent (thick, colored, opaque) rhinorrhea
Nasal congestion
Nasal congestion
Cough
Facial pain or headache
Headache, facial pain, and irritability (variable)
Periorbital edema (variable)
Low-grade or no fever
High fever (temperature ³ 39°C)




In children with subacute or chronic bacterial sinusitis the symptoms are protracted. Fever is rare, the cough and nasal congestion persist, and a sore throat (as a result of mouth breathing) is common.
The location of the facial pain can point to which of the sinuses is involved. Maxillary bacterial sinusitis is often associated with pain in the cheeks, frontal with the forehead, ethmoid with medial canthus, and sphenoid with occipital pain. Other suggestive factors are action or position that makes the sinus worse or better, and clues that suggest the presence of chronic infection.


Signs of Sinus Infection That Can Be Observed by Physical Examination:

• Mucopurulent nasal or posterior pharyngeal discharge.
• Erythematous nasal mucosa that may be pale and boggy.
• Signs of infection in the throat that can be associated with malodorous breath.
• Acute otitis media can be present in association with acute bacterial sinusitis, and otitis media with effusion with chronic bacterial sinusitis.
• Cervical lymphadenitis may be present but rare.
• Facial tenderness is inconsistent and nonspecific.
• Periorbital edema with skin discoloration can be present, especially in children with ethmoid sinusitis.
• Disease in the upper molar teeth may be the source of maxillary sinusitis.
Further work-up and consideration for hospitalization include suspicion of nosocomial sinusitis (recent intubation, feeding or suction device), patients who are immunocompromised, possible meningitis or other intracranial complications, or frontal or sphenoid sinusitis.

Clues for the sinuses involved can be ascertained from the location of the pain and tenderness:






The clinical picture of acute bacterial sinusitis
Ethmoid sinusitis
Frontal sinusitis
Maxillary sinusitis
Sphenoid sinusitis
Common complaints

Common complaints

Nasal congestion
Severe frontal headaches
Pain over the cheekbone on one side of the face
Deep headache with multiple foci (occipital with frontal, temporal, retro-orbital, or vertex)
Purulent rhinorrhea
Fever (typical but not always present)
Toothache
Fever of unknown origin
Inner canthal pain or pressure

Periorbital or supraorbital pain

Periorbital headache

Temporal headache

Temporal headache



Other suggestive factors

Other suggestive factors

Fever
Severe frontal headache associated with tenderness over the frontal sinus on percussion or palpation
Tenderness over the maxillary sinus

Nasal obstruction

Mucosal edema

Tenderness at the inner canthal area

Hypermia



Purulent drainage in the middle meatus



Positive PFR findings

Additional considerations


Additional considerations

Involvement of other sinuses often combined with acute maxillary sinusitis
Acute frontal sinusitis constitutes a medical emergency; surgical referral is indicated
Extreme pain may indicate need for surgical referral for decompression
Acute sphenoid sinusitis constitutes a medical emergency; surgical referral is indicated
Pus, erythema, and edema seen only endoscopically
Adolescent males particularly at risk for intracranial complications

May be difficult to diagnose by PFR studies; basal view may be helpful

Complications: meningitis, epidural abscess, subdural empyema, brain abscesses, and visual loss (uncommon but not rare)

Warning signs of impending CNS complications: diplopia, visual changes, and paresthesia involving the second branch of the fifth cranial nerve
Makes symptoms worse

Makes symptoms worse

Coughing
Lying supine
Maintaining the head in an upright position
Lying supine
Straining
Pressing thumb up against floor of frontal sinus (medial, superior to eye)

Bending forward or Valsalva's maneuver
Lying supine



Makes symptoms better

Makes symptoms better

Maintaining the head in an upright position
Maintaining the head in an upright position
Lying supine
Maintaining the head in an upright position
Clues to chronic bacterial sinusitis

Clues to chronic bacterial sinusitis

Triad of nasal obstruction, chronic rhinorrhea, or postnasal discharge, and low-grade discomfort
History of ostial trauma leading to long-standing inflammation
Malar discomfort
Low-grade, diffuse headache (common but not always present)
Patient pinching the bridge of the nose to demonstrate the area of discomfort
Persistent, low-grade frontal headache
Symptoms worse with upper respiratory tract infections or exacerbation of allergy

Symptoms worse in late morning and aggravated by wearing eyeglasses
Persistent sinus opacification on PFR
Discomfort typically worse throughout the course of the day

Recurrent sore throat and halitosis

Nocturnal cough

Recurrent secondary maxillary or frontal sinusitis



CNS = central nervous system; PFR = plain film radiography.




Required patient assessments, especially when complications are suspected are:

1. A complete head and neck examination (including the orbit, extra­ ocular motility, the response of the pupils, vision, and cranial nerve function)
2.Palpation and/or percussion (over the frontal sinuses, cheeks [maxillary sinuses], and medial orbit [ethmoid sinuses])
3. Bending the head forward (when sitting) and holding it at knee level for 45–60 s; this can elicit a sensation of fullness and pain at the involved sites
4. Assessment of nasopharynx for postnasal drip and obstruction caused by adenoid hypertrophy, choanal atresia, malignancy, polyps, and septal deviation
5. Nose examination, especially in chronic infection; anterior rhinoscopy is performed with a good light source after application of a topical decongestant; the presence of edema, erythema, crusting, or purulent secretion should be noted
6. Endoscopy may localize the pus within the nasal cavity and direct the examiner to the involved sinus(es); bacterial cultures can also be obtain; however, the specimens obtained may contain nasal mucosal flora.


DIAGNOSITIC TESTS

These include transillumination, mucociliary clearance testing, sinus aspiration, and rhinomanometry.

Transillumination

Transillumination is infrequently utilized because the findings do not always correlate with the disorder. The poor reproducibility between observers limits the use of this method.
Guidelines for performing transillumination
• Use a completely dark room, after the examiner’s eyes have adapted to darkness.
• Place a strong source of light (preferably a transilluminator) over the suspected sinus to see whether light can be transmitted.
• Examine the maxillary sinus by shining light through the sinus from the infraorbital area and observe its transmission through the hard plate.
• Test the frontal sinus by shining the light superiorly through the supraorbital ridge and observe transmission through the forehead; the bilateral symmetry of the flash needs to be evaluated.

Transillumination of the maxillary sinus


Sinus Aspiration and Endoscopy:

The indications for maxillary sinus aspiration are failure to improve on antimicrobial therapy, severe facial pain, orbital or intracranial complications, and in the immunocompromised host. Aspiration of the sinus for culture is the method of choice for determining the microbiology. Culture of nasal pus or of sinus exudate obtained by rinsing through the sinus ostium can give unreliable information because of contamination by the resident bacterial nasal flora. Collection of specimen for culture could also be attempted by using endoscopy, but there is the risk of contamination by nasal flora.



Needle aspiration of the maxillary sinus



Laboratory Assessment of Aspirated Material:

• Gram stain and leukocyte count.
• Aerobic and anaerobic bacterial, fungal, and mycobacterial cultures, using the proper transport systems.
• Viral cultures are done in selected cases and for research purposes.
• Quantitative bacterial cultures are useful. The recovery of organisms in a concentration of at least 10000/ml is considered to represent true infection rather than contamination.
• Gram and other special stains. Observing at least a single organism per high power field or gram stain of an aspirate correlates with the isolation of bacteria in a density > 100000 cfu/ml.
• Biopsy of the sinus mucosa provides greater accuracy in establishing the diagnosis of infection.





LABORATORY TESTING

Laboratory Tests for Patients with Recurrent Acute or Chronic Bacterial Sinusitis Include:


• Erythrocyte sedimentation rate (ESR). An elevated ESR may signify a systemic illness or osteomyelitis complicated sinusitis.
• Complete blood count.
• Serum immunoglobulin (to exclude underlying immunodeficiency).
• Sweat chloride evaluation (to exclude cystic fibrosis).
• Testing for human immunodeficiency virus (HIV) infection.
• Allergy testing is carried out when indicated.