Sinus infection

Sinusitis, also known as rhinosinusitis, is inflammation of the mucous membranes that line the sinuses resulting in symptoms that may include thick nasal mucus, a plugged nose, and facial pain. Other signs and symptoms may include fever, headaches, a poor sense of smell, sore throat, a feeling that phlegm is oozing out from the back of the nose to the throat along with a necessity to clear the throat frequently and frequent attacks of cough.

Generally sinusitis starts off as a common viral infection like common cold. This infection generally subsides within 5 to 7 days. During this time the nasal structures can swell and facilitate the stagnation of fluids in sinuses that leads to acute sinusitis which lasts from 6th day of the infection to 15th day. From the 15th day to 45th day of the infection comes the subacute stage followed by chronic stage. Whenever a chronic stage patient's immunity takes a hit the infection moves to "acute on sinusitis" stage and moves back to chronic when the immunity is up.

Sinusitis occurs only in individuals with underlying conditions like allergies, or structural problems in the nose and in people with lesser immunity against bacteria by birth. Most cases are caused by a viral infection. Recurrent episodes are more likely in persons with asthma, cystic fibrosis, and poor immune function. In early stages an ENT doctor confirms sinusitis using nasal endoscopy. Diagnostic imaging is not usually needed in acute stage unless complications are suspected. In chronic cases, confirmatory testing is recommended by either direct visualization or computed tomography.

Some cases may be prevented by hand washing, avoiding smoking, and immunization. Pain killers such as naproxen, nasal steroids, and nasal irrigation may be used to help with symptoms. Recommended initial treatment for acute sinusitis is watchful waiting. If symptoms do not improve in 7–10 days or get worse, then an antibiotic may be used or changed. In those in whom antibiotics are used, either amoxicillin or amoxicillin/clavulanate is recommended first line. Surgery may occasionally be used in people with chronic disease or in someone who is not responding to medicines as per doctor's expectation.

Sinusitis is a common condition. It affects between about 10 and 30 percent of people each year in the United States and Europe. Chronic sinusitis affects about 12.5% of people. Treatment of sinusitis in the United States results in more than 11 billion in costs. The unnecessary and ineffective treatment of viral sinusitis with antibiotics is common.

Signs and symptoms

Headache, facial pain, or pressure of a dull, constant, or aching sort over the affected sinuses is common with both acute and chronic stages of sinusitis. This pain is usually localized to the involved sinus and may worsen when the affected person bends over or lies down. Pain often starts on one side of the head and progresses to both sides.
Acute sinusitis may be accompanied by a thick nasal discharge that is usually green in color, and may contain pus or blood. Often, a localized headache or toothache is present, and these symptoms distinguish a sinus-related headache from other types of headaches, such as tension and migraine headaches. Another way to distinguish between toothache and sinusitis is that the pain in sinusitis is usually worsened by tilting the head forward and with the Valsalva maneuver.

Other symptoms associated with acute rhinosinusitis include cough, fatigue, hyposmia, anosmia and ear fullness or pressure. Text was copied from this source, which is available under
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Sinus infections can also cause middle-ear problems due to the congestion of the nasal passages. This can be demonstrated by dizziness, "a pressurized or heavy head", or vibrating sensations in the head. Postnasal drip is also a symptom of chronic rhinosinusitis.

Halitosis (bad breath) is often stated to be a symptom of chronic rhinosinusitis; however, gold-standard breath analysis techniques have not been applied. Theoretically, several possible mechanisms of both objective and subjective halitosis may be involved.

A 2005 review suggested that most "sinus headaches" are migraines. The confusion occurs in part because migraine involves activation of the trigeminal nerves, which innervate both the sinus region and the meninges surrounding the brain. As a result, accurately determining the site from which the pain originates is difficult. People with migraines do not typically have the thick nasal discharge that is a common symptom of a sinus infection.

Symptoms of chronic sinusitis may include nasal congestion, facial pain, headache, night-time coughing, an increase in previously minor or controlled asthma symptoms, general malaise, thick green or yellow discharge, feeling of facial fullness or tightness that may worsen when bending over, dizziness, aching teeth, and bad breath. Often, chronic sinusitis can lead to anosmia, the loss of the sense of smell.

By location

The four paired paranasal sinuses are the frontal, ethmoidal, maxillary, and sphenoidal sinuses. The ethmoidal sinuses are further subdivided into anterior and posterior ethmoid sinuses, the division of which is defined as the basal lamella of the middle nasal concha. In addition to the severity of disease, discussed below, sinusitis can be classified by the sinus cavity it affects:
* Maxillary – can cause pain or pressure in the maxillary (cheek) area (''e.g.,'' toothache, or headache) (J01.0/J32.0)
* Frontal – can cause pain or pressure in the frontal sinus cavity (located above the eyes), headache, particularly in the forehead (J01.1/J32.1)
* Ethmoidal – can cause pain or pressure pain between/behind the eyes, the sides of the upper part of the nose (the medial canthi), and headaches (J01.2/J32.2)
* Sphenoidal – can cause pain or pressure behind the eyes, but is often felt in the top of the head, over the mastoid processes, or the back of the head.

Complications

Complications are thought to be rare (1 case per 10,000).

The proximity of the brain to the sinuses makes the most dangerous complication of sinusitis, particularly involving the frontal and sphenoid sinuses, infection of the brain by the invasion of anaerobic bacteria through the bones or blood vessels. Abscesses, meningitis, and other life-threatening conditions may result. In extreme cases, the patient may experience mild personality changes, headache, altered consciousness, visual problems, seizures, coma, and possibly death.

Sinus infection can spread through anastomosing veins or by direct extension to close structures. Orbital complications were categorized by Chandler et al. into five stages according to their severity (see table). Contiguous spread to the orbit may result in periorbital cellulitis, subperiosteal abscess, orbital cellulitis, and abscess. Orbital cellulitis can complicate acute ethmoiditis if anterior and posterior ethmoidal veins thrombophlebitis enables the spread of the infection to the lateral or orbital side of the ethmoid labyrinth. Sinusitis may extend to the central nervous system, where it may cause cavernous sinus thrombosis, retrograde meningitis, and epidural, subdural, and brain abscesses. Orbital symptoms frequently precede intracranial spread of the infection . Other complications include sinobronchitis, maxillary osteomyelitis, and frontal bone osteomyelitis. Osteomyelitis of the frontal bone often originates from a spreading thrombophlebitis. A periostitis of the frontal sinus causes an osteitis and a periostitis of the outer membrane, which produces a tender, puffy swelling of the forehead.

The diagnosis of these complications can be assisted by noting local tenderness and dull pain, and can be confirmed by CT and nuclear isotope scanning. The most common microbial causes are anaerobic bacteria and '' S. aureus''. Treatment includes performing surgical drainage and administration of antimicrobial therapy. Surgical debridement is rarely required after an extended course of parenteral antimicrobial therapy. Chronic sinus infections may lead to mouth breathing, which can result in mouth dryness and an increased risk of gingivitis. Decongestants may also cause mouth dryness.

If an odontogenic infection involves the maxillary sinus, odontogenic sinusitis (ODS) may ensue. Odontogenic sinusitis can often spread to other sinuses such as the ethmoid, frontal and (less frequently) sphenoid sinus, and even to the contralateral nasal cavity. In rare instances, these infections may involve the orbit, causing orbital cellulitis, which may in turn result in blindness, or determine central nervous system complications such as meningitis, subdural empyema, brain abscess and life-threatening cavernous sinus thrombosis.

Infection of the eye socket is a rare complication of ethmoid sinusitis, which may result in the loss of sight and is accompanied by fever and severe illness. Another possible complication is the infection of the bones (osteomyelitis) of the forehead and other facial bones – Pott's puffy tumor.

Causes

Acute

Acute sinusitis is usually precipitated by an earlier upper respiratory tract infection, generally of viral origin, mostly caused by rhinoviruses (with RVA and RVC giving more severe infection than RVB), coronaviruses, and influenza viruses, others caused by adenoviruses, human parainfluenza viruses, human respiratory syncytial virus, enteroviruses other than rhinoviruses, and metapneumovirus. If the infection is of bacterial origin, the most common three causative agents are ''Streptococcus pneumoniae (38%)'', ''Haemophilus influenzae (36%)'', and ''Moraxella catarrhalis (16%)''. Until recently, ''H. influenzae'' was the most common bacterial agent to cause sinus infections. However, introduction of the ''H. influenzae'' type B (Hib) vaccine has dramatically decreased these infections and now non-typable ''H. influenzae'' (NTHI) is predominantly seen in clinics. Other sinusitis-causing bacterial pathogens include '' S. aureus'' and other streptococci species, anaerobic bacteria and, less commonly, Gram-negative bacteria. Viral sinusitis typically lasts for 7 to 10 days.

Acute episodes of sinusitis can also result from fungal invasion. These infections are typically seen in people with diabetes or other immune deficiencies (such as AIDS or transplant