What is the medical term for a sinus infection?

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Medical Term for Sinus Infection

The medical term for a sinus infection is rhinosinusitis, which is preferred over the older term sinusitis because inflammation of the nasal cavity nearly always accompanies inflammation of the contiguous paranasal sinuses. 1

Definition and Classification

Rhinosinusitis is defined as inflammation of one or more of the paranasal sinuses. The most common cause of rhinosinusitis is infection, though other causes exist. 1

Rhinosinusitis is classified based on duration of symptoms:

  • Acute rhinosinusitis: Symptoms lasting less than 4 weeks 1
  • Subacute rhinosinusitis: Symptoms lasting 4-8 weeks 1
  • Chronic rhinosinusitis: Symptoms lasting more than 8 weeks (or 12 weeks according to some guidelines) 1
  • Recurrent rhinosinusitis: 3 or more episodes of acute rhinosinusitis per year 1

Why "Rhinosinusitis" is Preferred Over "Sinusitis"

The term rhinosinusitis is now preferred over sinusitis for several important reasons:

  • Rhinitis typically precedes sinusitis
  • Sinusitis without rhinitis is rare
  • The mucosa of the nose and sinuses are contiguous
  • Symptoms of nasal obstruction and discharge are prominent in sinusitis 1

Clinical Presentation

Acute rhinosinusitis typically presents with:

  • Nasal congestion
  • Purulent rhinorrhea (anterior and/or posterior)
  • Facial pain or pressure
  • Postnasal drainage
  • Anosmia (loss of smell)
  • Headache
  • Fever
  • Cough (often worse at night) 1

Microbiology

The causative pathogens differ based on the type of rhinosinusitis:

  • Acute bacterial rhinosinusitis: Primarily caused by Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis 2, 3

  • Chronic rhinosinusitis: More commonly involves Staphylococcus aureus and anaerobic bacteria (Prevotella, Porphyromonas, Fusobacterium, and Peptostreptococcus species) 3, 4

  • Nosocomial or immunocompromised patients: Pseudomonas aeruginosa and other gram-negative rods are more common 3, 4

Types of Sinuses Affected

Rhinosinusitis can affect different sinuses, with varying symptoms and risks:

  • Maxillary sinusitis: Most common form, presenting with infraorbital pain that increases when bending forward 1

  • Frontal sinusitis: Presents with supraorbital headache and has a higher risk of intracranial complications 1

  • Ethmoid sinusitis: Can lead to orbital complications due to the thin bone (lamina papyracea) separating the sinuses from the orbit 1

  • Sphenoid sinusitis: Rare but potentially serious with retro-orbital headache radiating to the vertex 1

Clinical Relevance and Complications

Rhinosinusitis can have significant impacts on morbidity and quality of life:

  • It is one of the most common chronic illnesses in the United States, affecting approximately 12-16% of the population 1
  • The overall annual economic burden is estimated at $22 billion 1
  • Complications can include orbital cellulitis, subperiosteal abscess, intracranial abscess, cerebritis, and cavernous sinus thrombosis 1
  • Rhinosinusitis can trigger or worsen asthma 1, 5

Special Considerations

  • Fungal rhinosinusitis: Particularly concerning in immunocompromised patients, with acute invasive fungal sinusitis having mortality rates of 50-80% 1

  • Pediatric rhinosinusitis: Often follows viral upper respiratory infections, with 8% of viral infections complicated by acute viral sinusitis 1

  • Dental origin: Up to 20% of maxillary sinus infections may originate from underlying dental disease 1

Understanding the proper terminology and classification of rhinosinusitis is essential for accurate diagnosis, appropriate treatment selection, and effective communication among healthcare providers.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Microbiology and antimicrobial management of sinusitis.

The Journal of laryngology and otology, 2005

Research

Microbiology of chronic rhinosinusitis.

European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology, 2016

Research

Microbiology of sinusitis.

Proceedings of the American Thoracic Society, 2011

Research

Sinusitis in adults and its relation to allergic rhinitis, asthma, and nasal polyps.

The Journal of allergy and clinical immunology, 1988

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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