Acute sinusitis

p e c i a l f o c u s :
A c u t e s i n u s i t i s
The National Institute of Allergy and Infectious Diseases
DIAGNOSIS
reserved for patients with symptoms lasting from four to 12
(NIAID) estimates that 37 million Americans suffer from
weeks and chronic sinusitis is clinically defined by the pres-
Many patients who come into the office with a cold that just
sinusitis each year, accounting for $5.8 billion a year in relat-
ence of sinus signs and symptoms for more than 12 weeks.
won’t go away think they may have sinusitis, and it is indeed
ed health costs. Sinusitis is the fifth most common reason to
Chronic disease and recurrent episodes unresponsive to
often difficult to differentiate a lingering viral upper respirato-
visit a primary care physician, according to a 2005 study pub-
ry infection (URI) from acute sinusitis. In fact, acute sinusitis
lished in the Journal of Family Practice.
is usually a complication of a viral URI. Given the contiguity
A
“It is fairly predictable every year that during the winter there
of the sinuses with the nasopharynx, the term rhinosinusitis
dvanced imaging techniques
will be more in the way of viral illnesses and colds in a variety
is often preferred to characterize inflammation of both.
of different types of patients. Some of these patients develop
and other specialized studies
Patient history can differentiate infectious causes of rhinosi-
acute sinusitis,” said Kenneth Smith, FACP, assistant profes-
nusitis from those due to allergy or environmental irritants,
sor of medicine at the University of Pittsburgh Medical
may be required in patients
such as smoke or trauma. Although allergic rhinitis can pre-
Center, and editorial consultant for PIER’s module on acute
dispose patients to acute infection, other underlying condi-
sinusitis.
predisposed to unusual
tions more commonly cause chronic or recurrent sinusitis.
Most cases of sporadic acute sinusitis are due to viral or bac-
Some of these include:
bacterial infections
terial infection, while some are caused by trauma or exposure
I Diabetes
to noxious agents. Atopic disease, which occurs in about 15%
of the U.S. population, may predispose patients to sinusitis,
I HIV disease and immunosuppressive medications
treatment suggest the presence of an underlying condition
as does smoking.
I Anatomic abnormalities of the sinuses and nasal
that requires more extensive evaluation.
passages
Doctors are familiar with acute sinusitis in their practices, but
On physical examination, look for tenderness over the sinus-
the condition lacks an evidence-based definition, Dr. Smith
I Cystic fibrosis
es and pus in the nose and pharynx. In rare cases, spread of
continued.
The most important historical symptoms to inquire about are:
infection beyond the sinuses is apparent on examination of
the orbital structures or on neurological examination. Again,
“A lot of our decisions in terms of treatment are based on
I purulent rhinorrhea (rhinorrhea and facial pain may be
fever is not a distinguishing factor for acute sinusitis.
duration rather than whether or not sinusitis is present,” Dr.
unilateral or bilateral),
Diagnostic studies
In uncomplicated cases of acute sinusitis, avoid sinus
radiography, ultrasonography, CT or MRI. Many imaging
modalities have high false positive rates. Asymptomatic
patients may demonstrate abnormalities such as mucosal
thickening, fluid levels or sinus opacification that do not
require treatment. Ultrasonography, although less expen-
sive than plain sinus radiography, is rarely used in the
U.S. CT and MRI have no role in the diagnosis of acute
sinusitis except when history and physical examination
indicate local spread beyond the sinuses or intracranial
complications.
At a cost of approximately $100, sinus radiography is not
cost-effective or useful compared with symptomatic treat-
ment. The occipitomental (Waters) view is the standard for
visualizing the paranasal sinuses, especially the maxillary
sinuses; however a series of three or four X-rays is often
ordered. Radiographic abnormalities include sinus fluid
and opacity. Mucous membrane thickening increases sen-
sitivity but decreases specificity when compared with
sinus puncture. Acute viral sinusitis probably causes the
same radiographic changes as acute bacterial sinusitis.
There have been studies comparing radiography to CT and
ultrasonography, but there is no convincing evidence that
these two latter modalities offer any clear advantage.
Diagnostic imaging with CT or MRI has no role in the over-
all management of acute sinusitis but is clearly indicated
when clinical examination suggests spread of disease
beyond the sinuses or intracranial complications.
Advanced imaging techniques and other specialized stud-
ies may be required in patients predisposed to unusual
bacterial infections, such as those with underlying
Magnetic resonance image of sinusitis, showing inflammation of the mucous membrane.
anatomic abnormalities or immunosuppression. Such
patients may be infected with atypical microbial
pathogens, such as Pseudomonas aeruginosa or fungi, and a
Smith said. “Most people have viral sinusitis, which should
I localized facial pain (most often over the maxillary
precise bacteriologic diagnosis may be needed to determine
clear rather rapidly, whereas [those with] bacterial infections
sinuses) and
optimal therapy, especially when empirical therapy has failed
will tend to have symptoms longer or more severely.”
I duration of illness beyond seven days.
to achieve a satisfactory response. In such cases, sinus punc-
Symptom duration and severity are most often used to diag-
Although most sinusitis is probably caused by viral infection,
ture and culture of aspirate is the gold standard for diagnosis
nose acute sinusitis in patients with upper respiratory infec-
a few studies (using imaging criteria or the true gold stan-
and should only be performed by a specialist.
tions. For example, the risk of sinusitis is considerably higher
dard of sinus puncture and bacteriologic analysis) have found
when the patient’s upper respiratory infection has lasted for
that the above three factors correlate best with the diagnosis
Complications and consultations
seven days, or there is facial pain or purulent discharge.
of bacterial sinusitis. Good evidence is lacking for other
Most cases of acute viral sinusitis and even most cases of
“We’re dealing with a greater than 50% probability rather
symptoms such as fever, facial pain and pressure that worsen
acute bacterial sinusitis are self-limited and respond to sup-
than definite diagnostic criteria, and that makes studying an
on bending over, halitosis, maxillary toothache, and cough.
portive therapy. In patients with recurrent episodes of sinusi-
illness that much more difficult when you’re dealing with a
tis, it is often difficult to determine whether it is due to infec-
probability rather than a certainty.”
Duration of illness is important not only as a defining criteri-
tion with a new organism or a recrudescence of smoldering
on for acute sinusitis but also in management decisions. It is
This edition of
infection from an incompletely treated pathogen. Patients
ACP Observer Special Focus is designed to
important to distinguish between acute, subacute and chron-
help optimize your ability to diagnose, treat and manage
with chronic disease are often treated with multiple courses
ic sinusitis. Acute sinusitis is defined by duration of disease
patients with acute sinusitis.
of various antibiotics and may harbor resistant organisms. In
lasting for less than four weeks, subacute sinusitis is
these patients, chronic sinusitis has a different histopatholo-
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gy and prognosis, requiring advanced imaging and otorhino-
laryngologist consultation. When atopic disease is suspected,
Antibiotic drug treatment for bacterial sinusitis
allergist consultation may also be useful.
The most serious complications are the result of bacterial
sinusitis occurring in patients with chronic underlying dis-
Agent
Dosage
Side Effects
Notes
eases, such as diabetes, anatomic abnormalities or immuno-
suppression predisposing them to infection with unusual
Amoxicillin
Adults: 1.5-3.5 g/d divided bid-
Rash, gastrointestinal
One randomized controlled
pathogens. This can lead to local spread of disease causing
tid; Children: 45 mg/kg d divided
symptoms, hypersensi-
study suggests that amoxi-
osteitis of the sinus bones; periorbital and orbital cellulitis;
bid × 10-21 days or 7 days symp-
tivity reaction (rare),
cillin and amoxicillin-clavu-
and central nervous system manifestations, such as meningi-
tom free; High-risk children: 80-
lanate are no more effective
tis, brain abscess or infection of the intracranial venous
90 mg/kg d divided bid × 10-21
than placebo in children with
sinuses, particularly the cavernous sinus. Such complications
days or 7 days symptom free
sinusitis
are usually clinically evident. For example, orbital cellulitis is
diagnosed on the basis of orbital swelling, redness of the
Amoxicillin-
Dose based on amoxicillin
Side effects similar to
conjunctiva and limitation of extraocular movements. In such
clavulanate
component
those of amoxicillin
cases, otorhinolaryngologist, neurologist, infectious disease
and ophthalmologist consultation are most likely required.
Trimethoprim-
800/160 mg bid × 3-10 days
Rash, gastrointestinal
Consider in penicillin-allergic
TREATMENT
sulfamethoxazole
symptoms, hematologic
patients. Up to 20% pneu-
(rare), toxic epidermal
mococcal resistance
Although there are no well-designed studies to address their
necrolysis (rare)
effectiveness, it is reasonable to consider sinus irrigation and
over-the-counter saline to increase mucosal moisture and
Azithromycin
Adults: 500 mg/d on day 1, then
Gastrointestinal
Consider in penicillin-allergic
remove inflammatory debris and bacteria. Such measures
250 mg × 4 days; Children: 10
symptoms
patients. No proven benefit
may relieve patients’ discomfort, and the cost is low com-
mg/kg d on day 1, then 5 mg/kg d
over other agents.
pared with drug therapy.
× 4 days
Then begin to assess the need for further drug therapy by
Doxycycline
100 mg bid
Photosensitivity,
Not recommended in chil-
estimating the probability that the patient does or does not
× 7-10 days
neutropenia
dren
have bacterial sinusitis on the basis of the presence or
?8 years old.
absence of the same factors that led you to initially suspect
sinusitis (URI >7 days, facial pain, purulent drainage). The
probability of bacterial sinusitis is low if only one of these
sinusitis. However, if symptoms are severe, consider immedi-
Despite concerns about development of bacterial resistance,
factors is present and higher if at least two are present.
ate short-course antibiotic therapy. If symptoms are less
there are few data to suggest that newer, more costly broad-
severe, consider antibiotic therapy if there has been no
er-spectrum antibiotics are more effective in adults than the
If the probability of bacterial sinusitis is low, and especially if
improvement after seven to 10 days of symptomatic therapy.
older, narrow-spectrum agents recommended above. It is
symptoms are mild or moderate, most patients with rhinosi-
worth noting, however, that pneumococcal resistance rates
nusitis will improve without antibiotic treatment. Such
When using antibiotic therapy, use amoxicillin or amoxicillin-
for trimethoprim-sulfamethoxazole may be as high as 18% to
patients can be treated with symptomatic therapy including
clavulanate as a first-line agent. In penicillin-allergic patients,
20%, and this drug is not recommended in children.
an appropriate combination of the following agents:
consider doxycycline or trimethoprim-sulfamethoxazole in
adults and doxycycline in older children (but not in younger
Minor adverse reactions, mainly gastrointestinal, occur in
I mucolytic agents to reduce viscosity of nasal secretions
children). There are few data on the optimal duration of ther-
10% to 20% of patients taking amoxicillin, folate inhibitors
I decongestants to reduce mucosal inflammation and
apy. Most trials have been carried out for seven to 14 days,
and doxycycline, but the withdrawal rate in randomized trials
improve ostial drainage by causing vasoconstriction
but there is no firm evidence that such long courses are
of these agents is about 4% to 6%. In most cases, side
I antihistamines and intranasal steroids to inhibit inflam-
needed to treat acute bacterial sinusitis.
effects disappear when the drugs are discontinued.
mation
The predominant organisms in patients with acute bacterial
FOLLOW-UP
I appropriate doses of analgesics and antipyretics as
sinusitis since the 1970s are S. pneumoniae and H.
needed
influenzae. Studies done in the 1990s showed some contribu-
Symptoms of uncomplicated acute sinusitis usually resolve
within four weeks, and routine office visits may only increase
It should be recognized that some studies of these proteolyt-
tion from M. catarrhalis and some H. influenzae, producing
the cost of management of this generally benign condition
ic enzymes, alpha-adrenergic agonists, mucolytic agents,
beta-lactamases and making them resistant to penicillin and
without meaningful clinical gains. However, re-evaluate the
intranasal corticosteroids, and antihistamines have been
amoxicillin. These latter two organisms are sensitive to doxy-
patient when symptoms persist or new symptoms develop.
carried out in conjunction with antibiotics, have included
cycline.
Failure to improve or new and worsening symptoms may sug-
patients with chronic sinusitis, and have shown varying
Although randomized trials have demonstrated the effective-
gest complications, such as spread of infection beyond the
efficacy.
ness of antibiotics in treating acute sinusitis, there is a high
sinuses. In such cases, in addition to careful physical exami-
In patients with a higher risk of bacterial sinusitis with two or
spontaneous cure rate in patients given placebo, suggesting
nation, imaging studies and appropriate consultation may be
more of the above factors present, assess the severity of the
that some of the patients may have had viral sinusitis.
necessary.
patient’s symptoms. Unfortunately, there is no validated tool
Decision analysis suggests that initial empirical antibiotic
to assess symptoms quantitatively in patients with acute
therapy is most cost-effective when the expected prevalence
of bacterial sinusitis is high.
This information comes from the PIER module “Acute
Sinusitis” (http://pier.acponline.org/physicians/diseases/
d096/d096.html).
Conditions predisposing to sinusitis
The information included herein should never be used as a
substitute for clinical judgment and does not represent an
official position of ACP.
Local
Systemic
I Viral upper respira-
I Nasal polyps
I Immune deficiency
tory infections
I Foreign bodies
I Cystic fibrosis
I Allergic rhinitis
I Swimming and diving
I Dysmotile cilia
I Deviated nasal
syndrome
I Smoking
septum
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