24.1 Definitions

• Rhinosinusitis:

Nasal blockage/obstruction/congestion or nasal discharge + at least one of:

– Facial pain/pressure

– Hyposmia/anosmia

In addition, endoscopic and/or CT changes required to confirm symptoms above of acute rhinosinusitis (ARS)/chronic rhinosinusitis (CRS)

<12 weeks = acute

>12 weeks = chronic

Symptom-free intervals (complete resolution) but >12 weeks in total = recurrent acute

<10 days = common cold (viral upper respiratory tract infection, i.e., URTI)

Increase in Sx after 5 days OR persistence of Sx after 10 days = non-viral ARS

Severity defined by VAS (0–10)—“How troublesome are your Sx of ARS/CRS?”:

– Mild = 0 to 3

– Moderate = >3 to 7

– Severe = >7 to 10

• Epidemiology:

ARS:

– 8.4% of Dutch population suffer with ≥ 1 episode of ARS/year

– Fifth most common reason for ABx prescription in the United States

CRS:

– 11% of population suffer with CRS (prevalence)

– ≥15% of outpatient consultations in ENT

– 10,000 sinus procedures per year in the United Kingdom (1999–2010)

– Cost of $500 per year to patients with CRS in the United States

– Increasing incidence of CRS with increasing age—mean age of 53

– Slight male preponderance

– AFRS accounts for ~10% of CRS with nasal polyps (CRSwNPs)

24.2 Aetiology

24.2.1 Acute Rhinosinusitis

• Bacterial superinfection of virally damaged mucosa:

Bacteria

– Streptococcus pneumoniae

– Haemophilus influenzae

– Moraxella catarrhalis (esp. children)

• Ciliary impairment—impaired by viral infection

• Allergy—may be a factor but evidence limited

• Helicobacter pylori and laryngopharyngeal reflux (LPR)—little evidence

• Presence of NG tube

24.2.2 Chronic Rhinosinusitis without Polyps

• Ciliary impairment—secondary ciliary dyskinesia

• Allergy—may be present in 50 to 90% of patients

• Asthma—many asthmatics will show abnormal mucosal CT findings (approximately 88%)

• Immunocompromised state—low IgA, IgG, IgM; HIV

• Genetics—CF (mutations of CFTR gene) and primary ciliary dyskinesia

• Pregnancy—11 to 32% of women suffer pregnancy rhinitis

• Local host factors—conflicting evidence for DNS, conchae bullosae, etc. Beware of dental infections

• Micro-organisms:

Bacteria—pathogens or colonizers?

– S. aureus (36%)

– Coagulase–ve staphylococcus (20%)

– Streptococcus pneumoniae (17%)

Fungi—colonize only or promoters of allergic/eosinophilic response?

• Osteitis—animal studies only—may explain resistance to ABx

• Environmental:

Smoking

Low income

Atmospheric pollutants—no convincing evidence

• Iatrogenic:

Mucoceles associated with previous ESS

Recirculation of mucus from natural to surgical ostia

• Helicobacter pylori and LPR—DNA detected in 11 to 33% of CRS patients—causal?

• Polyps present in 0.5 to 4.3% of the population; only two-third seek medical advice

• Allergy—varying reports between 10 and 81%

• Asthma—31 to 42% of patients with NPs (7% of asthmatics have NPs)

• Aspirin sensitivity—36 to 96% have CRS with NPs

• Genetics:

14 to 52% have +ve family history

Twin studies do not show that both develop NPs

HLA associations, e.g., A74, DR7

Gene polymorphisms

Multiple gene expressions for immune modulation

Cystic fibrosis

• Environmental factors—unclear

24.3 Children

• Day care

• Nasal obstruction

• Passive smoking

• Bottle-feeding

• Urban atmospheric pollution

• Tonsillitis (immunological deficiency)

• OME (immunological deficiency)

• Ciliary dyskinesia, e.g., CF, primary ciliary dyskinesia

24.4 Inflammatory Mechanisms

24.4.1 Acute Rhinosinusitis

• Elevation of IL-1, IL-6, IL-8

• Neutrophils—source of IL-8 and TNF-α

• Expression of intracellular adhesion molecule 1 (ICAM-1)

• T lymphocytes—stimulated by IL-1 and 6, TNF-α

24.4.2 CRS without NPs

• Neutrophils predominate

• Small numbers of eosinophils, mast cells, basophils

• Mucosal changes:

BM thickening

Goblet cell hyperplasia

Subepithelial oedema

Mononuclear cell infiltration

• CD4+ TH cells—initiate and regulate inflammation

• Macrophages (CD68+ cells) increase

• Mast cell numbers raised

• Cytokine mediators: IL-1, 3, 6 and 8; tumour necrosis factor-α (TNF-α), GM-CSF, ICAM-1, MPO, and eosinophil cationic protein (ECP)—the latter is the main difference from ARS

• IFN-γ and TGF-β = T_H 1 pathway; TGF-β expression higher than CRS with NPs

• Chemokines, e.g., CCR4+

• Eicosanoids—COX-2 mRNA and PGE2 higher than CRS with NPs

• Metalloproteinases—low MMP-9 activity

• Nasal nitric oxide (nNO) shows increase the correlates with subjective and objective measures of improvement

• Neuropeptides such as VIP may play a role

• Mucins—MUC5AC and MUC5B increased in CRS

• Increased vascular endothelial growth factor (VEGF)

• Biofilms—structured specialized communities of adherent micro-organisms encased in a complex extracellular polymeric substance (EPS)

24.4.3 CRS with NPs

• Eosinophils present in 80% = marker of inflammation in CRSwNPs

• Increased numbers of T cells and plasma cells

• S. aureus superantigens interact with T cells in 35%

• Macrophages increased with an increase in macrophage mannose receptors in polyps

• Mast cells—more often IgE+

• Increased neutrophils

• Overexpression of MUC8 mRNA and downregulation of MUC5AC mRNA expression—alters mucus composition

• Cytokines and chemokines—differences from CRSsNPs:

IL-5 and IgE = CRS with NPs (T_H2)

Exaggerated humoral and cellular response to airborne fungi

• Adhesion molecules—ICAM-1 among others expressed on polyp surface

• Leukotrienes and their receptors unregulated in NP tissue

• S. aureus enterotoxins induce a more severe eosinophilic inflammation and cause multiclonal IgE synthesis

• Aspirin sensitivity—inhibition of cyclooxygenase-1 causing release of lipid and non-lipid mediators

• IgE+ cell numbers raised in patients with allergic, fungal, and eosinophilic CRS

• Fungal-specific IgG and IgA higher in CRS with eosinophilic mucus

24.5 Investigations

• Endoscopy

• Endoscopic-guided nasal swabs—87% accurate

• CT scan (± MRI where neoplasia suspected)

• Lund–Mackay scoring system for CT:

0 to 2 score for each of maxillary, ant. ethmoid, post. ethmoid, sphenoid, frontal

Score of 0 or 2 for OMCs

Max. score = 24 (12 each side)

• Saccharin test for mucociliary clearance—useful if normal (<35 minutes)

• Ciliary beat frequency (>8 Hz for IT = normal) and electron microscopy for PCD

• Nitric oxide:

LRT = <20 ppb

Nose = 400 to 900 ppb

Sinuses = 20 to 25 ppm

• Nasal airway—PIFR/acoustic rhinometry/rhinomanometry/nasal spirometry