Chronic (and acute) sinusitis (& cystic fibrosis, hypogammaglobulinemia)

Clinical

• chronic sinusitis is a common, difficult, and frequently missed diagnosis in pediatrics
• can have symptoms of chronic cough, fetid breath, sore throat, and purulent nasal discharge for prolonged periods of time before the diagnosis is made. Other signs and symptoms facial pain and headaches (rare), painless morning eye swelling, sore throat, nausea, fetid breath, fatigue, and possibly exacerbation of asthma.
• it can be difficult to distinguish between sinusitis and recurrent viral infections.
• One clinical clue to the diagnosis of chronic sinusitis is a cough that responds rapidly to antibiotic therapy but recurs shortly (within 1 week) after discontinuation of the therapy.

Definitions

• Definition of acute bacterial sinusitis (ABS): nasal and sinus sx present at least 10 days and fewer than 30 days. A less common presentation of ABS is a 'cold' that seems more severe than usual defined by: fever >39 and, concurrently, purulent nasal discharge 3-4 days. 
• Subacute sinusitis: >4 wks and < 3 mos. Sore throat results from chronic mouth breathing due to nasal obstruction. Nasal discharge and headache are less common. Fever is rare.
• Chronic sinusitis: 3 mos or more
• Most uncomplicated episodes of viral rhinosinusitis last 5-7 days. Fever is usually present at onset of illness, but disappears and respiratory sx begin, and nasal secretions may start watery, become thick, colored, opaque, purulent for several days, then clears back again to mucoid or watery before resolving.  By day 10 they may still be symptomatic, but should be always improved.

Microbiology

• Chronic sinusitis predominantly is associated with aerobic organisms, including
  • Streptococcus pneumoniae (most common, 30-40%) -resistance by altered PBP
  • nontypeable Haemophilus influenzae (20%) - may produce B-lactamase therefore amox resistant
  • Moraxella catarrhalis.  (20%) - may produce B-lactamase therefore amox resistant
  • Other organisms causing chronic sinusitis include alpha-hemolytic streptococci
  • Staphylococcus aureus and anaerobes are uncommon.
  • In one study of children undergoing surgery for sinusitis, 76% had aerobes isolated whereas only approximately 8% had anaerobic organisms.
• life-threatening complications can include
  • meningitis
  • osteomyelitis - Pott's puffy tumor = area of edema surrounding regions of skull osteo - involved bone has doughy consistency
  • epidural, subdural, or brain abscess
  • cavernous or sagittal sinus thrombosis.
• The proximity of the ethmoid and maxillary sinuses can lead to preseptal cellulitis or involvement of the orbit, which can progress to proptosis, chemosis, decreased vision, and impaired ocular mobility.
• Infections of the ethmoid or frontal sinuses can spread into the cranial cavity, causing meningitis or epidural, subdural, or brain abscess.
• Infections of the maxillary sinus anteroinferior walls can lead to destruction of tooth buds as well as sepsis, which can spread by venous drainage of the face to the cavernous sinus, resulting in cavernous sinus thrombosis and stroke.
• Indication for maxillary sinus aspiration by ENT: failure to respond to multiple courses of ABX, severe facial pain, orbital or intracranial complications, evaluation of immunocompromised host.

Radiologic considerations

• Imaging is controversial; recent guidelines emphasize clinical diagnosis
• Plain films, indication: older children w/ recurrent acute sinusitis, vague sx, poor response to abx, or hx of ABX hypersensitivity that makes therapy risky. Get three views of the paranasal sinuses. The waters view (head tilted up) is done to move the temporal bone/auditory canal down on the film; in a direct AP view, they appear right behind the maxillary sinuses, confusing the picture. also look at the adenoids behind the nose. Radiologic findings c/w ABS include diffuse opacification, mucosal thickening of at least 4mm or air fluid level.
• CT, indication: complicated ABS or surgical candidates due to recurrent or chronic sinusitis; any patient w/ proptosis, impaired vision, notable swelling of forehead/face, deep seated headaches, or toxic appearance. CT scan does not distinguish between mucosal abnormalities due to ABS or cold. CT scans are normal in 1/3 of patients w/ sx of chronic sinusitis.

Differential

• Adenoidal hypertrophy can predispose to ABS, or when infected masquerade as sinusitis. Note: Adenoids normally involute significantly during puberty.
• Panopacification of the sinuses may be associated with an immunologic disorder (eg, hypogammaglobulinemia) or cystic fibrosis. Thus, such findings on radiography warrant an evaluation of the child for these underlying diseases.
• The child described in the vignette should have a sweat chloride test because this is the diagnostic test of choice for suspected cystic fibrosis.
• Quantitative measurement of serum immune globulins would be indicated to evaluate for immune globulin deficiency.
• A complete blood count with differential would be unhelpful in determining the cause of this child's chronic sinusitis.
• A nasal smear also is not necessary because it would be expected to reveal sheets of neutrophils.
•  Rhinoscopy would be indicated if a nasal foreign body is suspected, but this would be a very unlikely cause of panopacification.
• Serum immunoglobulin E measurement is unnecessary because allergic rhinitis rarely causes panopacification of the sinuses.
• Rare systemic disorders: Cystic Fibrosis, Kartagener syndrome, Wegener granulomatosis, TMJ syndrome

Treatment

• CDC, AAP suggest amoxicillin (regular dose) is a reasonable first choice for ABS in children, especially if uncomplicated, mild-mod severity, and not recently tx'ed (<1 month) w/ abx
• however, resistant S pneumoniae is more common. Indications for more than just reg dose amox include:
  • failure to improve with conventional dose amox
  • recent tx w/ amox (<1 mo)
  • day care
  • frontal or sphenoidal sinusitis
  • subacute sinusitis (>1 month sx)
• Alternatives include:
  • high dose amox 80-90 mg/kg/d
  • augmentin (80-90 mg/kg/d amox)
  • amox 45 mg/kg/d PLUS augmentin (45 mg/kg/d amox)
  • cefdinir (omnicef)
• appropriate duration of tx has not been studied systematically
• most can be tx'ed w/ 10-14 days. longer courses have been used in those who have chronic sinusitis to avoid surgery
• the use of antibiotic therapy for more than a few weeks is not supported by clinical studies, exposing patients to developing allergic hypersensitivity and inducing resistance
• Patients should improve in 48 hours. If not, clinical re-evaluation is approppriate
• adjuncts like antihistamines, decongestants, and antinflammatory agents have received little evaluation.
• topical decongestant sprays (phenylephrine (Neosynephrine), oxymetazoline(Afrin) 1-2 spray bid) can be used for 3 days max, to avoid rebound nasal congestion (rhinitis medicamentosa) - if this happens, dc spray and start short course of topical steroid
• oral decongestants like pseudoephedrine may be used up to one week.
• topical intranasal steroids: very modest beneficial effect does not justify their use.
• saline nasal irrigation using hyper or isotonic solutions has been shown to have a positive effect on some patients
•  

The time to refer a patient who has sinusitis is when he or she continues to have recurrence of disease after adequate treatment. This usually requires 3 weeks of antibiotic therapy, sometimes also including topical nasal therapy. Referral to either an allergist or ENT physician is appropriate, depending on whether allergy is suspected. The allergist would evaluate for possible triggers that are causing the nasal obstruction and subsequently the recurrence of sinusitis. The ENT physician is better able to evaluate the structural features of the sinuses and perform any necessary surgical interventions.

Pathogenesis:

• maxillary and ethmoid sinuses are present at birth, but small
• ethmoid: multiple air cells, each draining through an ostium to middle meatus; narrow caliber predisposes to obstruction
• frontal sinus develops from an anterior ethmoid cell and moves above orbital ridge by 6th birthday
• sphenoid: behind ethmoids and in front of pituitary fossa. Isolated involvement of sphenoid sinus is rare; usually infected as part of a sinusitis
• osteomeatal complex (OMC) = the confluence of drainage of the frontal, ethmoid and maxillary sinuses (between the middle and inferior turbinates). Here mucosal surfaces may touch and cilia may move in opposite directions, creating the potential for infection even without physical destruction of the ostia
• in cystic fibrosis, alterations in the mucus impairs ciliary activity

DDX:

• Mild-to-severe asthma usually begins slowly and subtly; some children present with an acute first exacerbation in conjunction with a viral upper respiratory tract infection. However, even in these cases, symptoms appear episodically and do not last for many months
• Bronchitis is rare in children, especially in the summer months, and it responds at least to some extent to beta agonist therapy. The duration of the symptoms rules out the possibility of acute sinusitis that, by definition, is short-lived.
• Allergy could be a source of the child's symptomatology if a new pet or allergen has been introduced recently

References:
Slavin RG. Nasal polyps and sinusitis. In: Middleton E Jr, Reed CE,
Ellis EF, Adkinson NF Jr, Yunginger JW, Busse WW, eds. Allergy:
Principles and Practice. 5th ed. St Louis, Mo: Mosby-Year Book, Inc;
1998:1024-1035
Slavin RG. Nasal polyps and sinusitis. JAMA. 1997;278:1849-1854
Sly M. Allergic rhinitis. In: Behrman RE, Kliegman RM, Jenson HB, eds.
Nelson Textbook of Pediatrics. 16th ed. Philadelphia, Pa: WB Saunders
Co; 2000:662-663

Pediatrics in Review 22(4) april 2001