Preseptal and Orbital Cellulitis, Research Paper Example

Background

The Merck Manual reports that orbit infections are not very common but they are devastating infections that might lead to meningitis, blindness or even death (2009). It is very important for the emergency physician to take accurate and rapid diagnosis and initiate therapy so that the patients does not end up being visually impaired which often occurs when patients do not get the definitive treatment in good time. The fibrous sheet that is peripherally attached around the orbit’s margin is called the orbital septum. It is fused centrally into tarsal plates where it separates the orbital cavity’s contents from the eyelids. The Merck Manual also reports that orbital cellulitis is potentially life-threatening (2009). However, it is an uncommon infection that is often characterized by infection of soft tissues that are found behind orbital septum. Preseptal cellulitis is more common but less serious. It is an infection found on the anterior side of the orbital septum. It has been reported that preseptal cellulitis usually progresses to the adverse conditions of orbital cellulitis if untreated. This often occurs in young children.

Epidemiology

It has been found that preseptal cellulitis is more common than orbital cellulitis although the data that relates to exact incidence is scarce. Both orbital and preseptal cellulitis occurs mostly during the winter seasons. This is because of the high incidence of the paranasal sinus infections. The diseases affect male and female alike, and also black, white, Asians, Arabs and he Indians. However, orbital cellulitis affects female children more than the number of male children. It has been discovered that both orbital and preseptal cellulitis occur mostly in children. Orbital cellulitis affects seven to twelve year olds while preseptal cellulitis affects children at younger ages (below ten years). Orbital and preseptal cellulitis both occur after eyebrow piercing in most people. Karkos, Karagama, Karkanevatos Et al suggest that the examinations carried out for preseptal cellulitis show that it is unilateral, there is swelling of eyelids, tenderness, periorbital area and also erythema (2007). The cause might be a mild fever, history of sinusitis or local skin bites or abrasions. There is an intense oedema that makes it hard to open the eye lids. There is also the occurrence of normal or blurred vision. In orbital cellulitis, it has been discovered that it is also unilateral, there is a rapid onset of swelling and also erythema, and there is also a case of diplopia, system malaise and fever. Pain and lid oedema and erythema are characteristics of orbital cellulitis.

Pathophysiology

There subperiosteal fluid collections where some are quite large often accumulate.  These fluid collections are called subperiosteal abscesses. It has however been discovered that many of these abscesses are sterile initially. Karkos, Karagama, Karkanevatos Et al report that the complications of orbital cellulitis include; optic neuropathy often caused by high or increased intra-orbital pressure, vision loss often from ischemic retinopathy, ophthalmoplegia (restricted ocular movements) usually caused by inflammation of the soft-tissues, cerebral abscess, meningitis, cavernous thrombosis and lastly the intracranial sequelae usually from the central spread of infection (2007). It has been discovered that orbital cellulitis often occurs in three situations; direct inoculation of orbit from surgery or trauma; the extension of an infections usually from periorbital structures which are most commonly got from the paranasal sinuses, but they can also be from the globe, the face, and also the lacrimal sac; and a spread from bacteremia which is usually hematogenous. The Merck Manual reports that the orbital’s medial wall is often thin and perforated by; numerous nerves, blood vessels and also by other defects for example the Zuckerkandl dehiscences (2009). This combination of foramine for the neurovascular passage, thin bone and the defects that occur naturally in the bone allows communication of the infectious organisms between the subperiorbital space that is located in the orbit’s medial section and the ethmoidal air cells. The most common and frequent location of the subperiorbital abscess is usually along the medial part of the orbit wall. The periorbital is relatively loosely supported to the medial orbital wall’s bone. This allows the abscess material to move easily either; superiorly, laterally and also inferiorly within the space in the subperiorbital. In addition, the intermuscular septa and the lateral extensions usually of sheaths of muscles that are extraocular extend from one of the rectus muscle to closest or next muscle and also from the muscles’ insertions to their origins which are often at the annulus of the Zinn posteriorly. The fascia which is located posteriorly to the orbit is often between the rectus muscles. It is often incomplete and thin and this allows the extension between the intraconal and extraconal orbital spaces to be easy. The venous drainage which is from the middle of a person’s face, the paranasal sinuses included is often through the orbital veins. These orbital veins do not have valves hence they allow the passage of various infections both retrograde and anterograde. Infectious materials can be introduced into a person’s orbit directly from surgical trauma or accidental trauma. The pathogens vary by age and etiology. Streptococcus pneumonia is one of the most frequent pathogen that causes the sinus infection. Raja and Singh report that Streptococcus pyogenes and Staphylococcus aureus predominate when infections caused local trauma arises (2005). Haemophilus influenzae often type “b” was once one of the common causes but due to vaccination which is widespread, it has become less common. Fungi are not common pathogens but once present they cause orbital cellulitis in immunosupressed and also diabetic patients. It has been reported that patients who are under that age of nine years old are often and typically infected with single aerobic organism. The patients who are above the age of 15 are infected by a mixture of anaerobic and aerobic organisms (polymicrobial). It has been discovered that ethmoid is one of the most common cause cellulitis especially orbital cellulitis in almost all the age groups. It has also been reported by Raja and Singh that non-spore-forming aerobic bacteria are the type of micro-organisms that are frequently responsible (2005).

Pathophysiology of Orbital Cellulitis

Orbital cellulitis is often different from that of preseptal cellulitis. It has been discovered that orbital cellulitis occurs as an extension of the preseptal cellulitis. This mostly occurs in young children whom orbital septum has not yet fully developed. The pathogens involved are; Staphylococcus aureus, Streptococcus pneumonia, Streptococcus pyogenes and also Haemophilus influenzae. Diabetic ketoacidosis patients and also the immunosupressed people have mucormycosis. Orbital cellulitis is not very common but it is aggressive and also fatal. Anari, Karagama, Fulton, et al reported that after organisms were isolated, there has been an emergence of Staphylococcus aureus which is Methicillin-resistant (MRSA) (2005). This organism is very rare but its development is worrying. Orbital cellulitis has been found to be complicated by the spread to central nervous system and also to the adjacent structures.

The Pathophysiology of Preseptal Cellulitis

Preseptal cellulitis occurs due to the following; spread from hordeolum, dacrocystitis and paranasal sinuses which are all local infections and also the spread from infections which are distant for example those from upper respiratory tract. The common pathogens that cause preseptal cellulitis are Streptococci, anaerobes, S. aureus, and S. epidermidis. The MRSA in the microbiology laboratories has also been isolated in cases of preseptal cellulitis but they are still rare. The orbital septum has been found by Blomquist to limit the spread to a person’s Central nervous system and also to the associated structures (2006).

The frequency of orbital cellulitis has been found to have increased world wide especially during the winter seasons. This is because of the increased incidence of infections such as sinusitis in the cold harsh weather. In the United States of America alone, there has been a noted increase in orbital cellulitis’ frequency due to community-acquired MRSA infections that cause orbital cellulitis. Community acquired infections are those infections got from other people living in the same area and also sharing the same items. This happens in homes, classes, social places and other locations. Hospital acquired infections are the infections that a person acquires right after one has been admitted to ICU and initially before the person entered the hospital, he did not have the infection but while he is in the hospital or leaves the hospital, he has the infection. This can be caused by poor handling of wounds or not using sterilized equipments when operating patients. Most of the hospital acquired infections are due to negligence of the doctors and the nurses but measures have been taken against such cases in the sense that, the health facility now pays for health insurance on the patients who have acquired hospital infections. Before the patients are treated and compensated, they are first tested when they enter the hospital door so that the doctors can know if the patients came with the infections or they acquired them while undergoing treatment. It has been reported that prior to availability of antibiotics, people who suffered from the orbital cellulitis had a mortality rate of about 17% and the survivors who ended up being in the infected eye (s) were about 20%. However, with quick diagnosis and the appropriate or correct use of the prescribed antibiotics, the rate through the years has been significantly reduced. Today blindness only occurs up to about 11% of the entire cases world wide. A major set back is the MRSA which most of the times has lead to blindness despite all the antibiotic treatment. This is solely because the MRSA has either mutated or it has acquired resistant genes from the other organisms.

Causes of Orbital Cellulitis

Organisms often gain access through the thin bones on the orbit walls, foramina, dehiscences and also the venous channels to the orbit. The infection can also be caused by the extension of an infection from the ocular adnexum, other tissues, sinuses, eyelids or the globe. Orbital cellulitis can follow the phlebitis of facial veins, dental infections, and osteomyelitis of orbital bones and also dacrocystitis. The infection can also be caused by any injury that perforates the orbital septum. Inflammation in the orbit will be noted after about 48-72 hours after orbital injury. The inflammation can also occur when a foreign body has been retained in the orbit. Orbital fractures may also lead to orbital cellulitis. Surgical procedures also cause orbital cellulitis. Orbital decompression, eyelid surgery, retinal surgery, strabismus surgery, and also postoperative endophalmotis cause orbital cellulitis. Mucormycosis in distribution has been noted to be widespread. Aspergillosis on the other hand has been reported to be frequent in the warm humid climates. Mucormycosis has a quick onset of about a week while Aspergillosis has about several months to years. It has been discovered that Aspergillosis initially displays decreased vision and proptosis. The mucormycosis displays a condition called orbital apex syndrome. This disease involves the orbital sympathetic and the cranial nerves (2, 3, 4 and 6). The condition causes vision loss, pain, lid oedema and also proptosis. It has been discovered that while the two conditions may lead to palatal and nasal necrosis, Aspergillosis causes nonnecrotinizing granulomatous process and also chronic fibrosis while mucormycosis causes ischemic necrosis and thrombosing arteritis.

Signs and Symptoms of Preseptal and Orbital Cellulitis

In orbital cellulitis, there is decreased vision, pain when the eye is moved, elevated intraocular pressure, and also conjunctival chemosis. Headache, fever, rhinorrhea, increased malaise and also lid oedema are symptoms that accompany the orbital cellulitis. Ophthalmoplegia and proptosis are often the physical cardinal symptoms and signs or orbital cellulitis. These symptoms have been found to advance more rapidly and eventually resulting to prostration. The other common signs and symptoms include dark red discolouration on the eyelids, hyperemia of conjunctiva, and the globe’s resistance to retropulsion. Purulent nasal discharge is also present. The signs of primary infection in orbital cellulitis are often present. These include bleeding with sinusitis, swelling with abscess and also periodontal pain. Raja and Singh report that Preseptal cellulitis causes swelling, tenderness, discolouration or redness of the eyelid (violaceous in children with H. influenzae), patients may also have difficulties when trying to open their eyes but the visual acuity often remains normal (2005).

Diagnostic Tests

Diagnosis is mainly through clinical elevation and also MRI or CT in cases of orbital cellulitis. Diagnosis is suspected clinically when there is trauma, retained foreign bodies, animal or insect bites, tumors, inflammatory orbital pseudotumor and also allergic reactions. It has been discovered that preseptal and orbital cellulitis can be distinguishable clinically. Preseptal cellulitis is often the case when there is lid swelling but the eye findings are normal or presence of an infection by a local nidus on the skin. In cases where examination is difficult especially in children, MRI or CT should be performed to know if orbital cellulitis is present. Most of the cases, tumor and pseudotumor are excluded and a diagnosis of the sinusitis carried out if it is present. In cases of cavernous sinus thrombosis, it has been discovered that MRI is best considered as compared to CT. Proptosis’ direction can be a clue to infection’s site. Blood cultures are also carried out. This is done before a patient is put on antibiotics especially those suspected to have orbital cellulitis. When the blood are cultured, the laboratory technicians look for the growth of fungi, sensitivity and specificity tests are carried out to know which drugs are most effective. Sensitivity testing is where the fungi are cultured in a media then drugs are put on top of the fungi and the plates are incubated overnight. The next morning, if fungi grew all around the drugs, then the fungi are resistant to that particular antibiotic but if the fungi formed a clear ring around the drug (grew centimeters away from the drug) then the fungi is susceptible towards the antibiotics and this can be used for treatment. Tests are also carried out to find if the agents or the pathogens are host-specific. These are the old diagnostic tests because most blood cultures are negative in adults; the current tests include full blood count frequencies which show leucocytosis. These can be counted on or relied on to often differentiate between the orbital and preseptal cellulitis. CT is carried out in case of sinusitis or on the orbit. In cases where meningeal or cerebral signs develop, a person needs a lumbar puncture. Blomquist suggested that throat and skin swabs and also nasal secretion samples are taken to the microbiology laboratory for tests (2006).

Treatment and Prognosis

Initial treatment regimens were initially instituted before the pathogens were identified. These include: a combination of aminoglcoside and the 1^st generation cephalosporins. With the constant change in technology patients with preseptal cellulitis are given drugs orally. These drugs include co-amoxiclay (250qds-500tds) mg for adults where they are given ten days to recover with follow up and co-amoxiclay (20-40) mg/kg a day for children. The lid abscesses are often drained. In orbital cellulitis, patients are admitted under the joint special care of ENT surgeons and the ophthalmologists. Intramuscular or intravenous antibiotics are used here. Ceftriaxone often 1-4mg is combined with flucloxacillin which is 1-2gm daily and also metronidazole are all used in patients who are over the age of ten and suffer from chronic sinonasal disease. It has been discovered that clindamycin with the combination of quinolone (ciprofloxacin) are used in cases where penicillin is sensitive. Vancomycin has also been discovered to an alternative antibiotic. The monitoring of the optic nerve function is done after every four hours (visual acuity, papillary reactions, light brightness appreciation and colour vision). Blomquist reported that surgery is often indicated in cases; CT evidence of orbital collection, no response to treatment using antibiotics, visual acuity decreases and lastly where a common picture that warrants diagnostic biopsy (2006).

Prognosis

Blomquist researched that 5 in 10 patients often experience recurrence in both preseptal and orbital cellulitis (2006). One in ten children with orbital cellulitis develops meningitis or intracranial pressure that is increased, all which can be resolved by hyperosmotic agents. Death cases are not common when the patients are undergoing treatment. In the end, all the patients recover fully.

Conclusion

The Streptococci are now the predominant cause. Orbital cellulitis caused by H. Influenza still occurs in young children but in rare cases. The antibiotics used to cure these two conditions are so far the best and also the use of improved and current diagnostic tests have helped in managing orbital and preseptal cellulitis.

References

Anari S, Karagama YG, Fulton B, et al. (2005) Neonatal disseminated Methicillin-resistant Staphylococcus aureus. Orbital cellulitis. 119(1):64-67.

Artac H, Silahli M, Keles S, Ozdemir M, Reisli I (2007). A rare cause of preseptal cellulitis:  Pediatr Dermatol. 24(3):330-1 retrieved 10^th Dec 2009 from http://www.medscape.com/medline/abstract/17542898

Babar TF, Zaman M, Khan MN, Khan MD (2009). Risk factors of preseptal and orbital cellulitis. J Coll Physicians Surg Pak. 19(1):39-42 retrieved 10^th Dec 2009 from http://www.medscape.com/medline/abstract/19149979

Blomquist PH (2006). Methicillin-resistant Staphylococcus aureus infections of the eye and orbit (an American Ophthalmological Society thesis). Trans Am Ophthalmol Soc. 104:322-45.

Boden JH, Ainbinder DJ. (2007). Methicillin-resistant ascending facial and orbital cellulitis in an operation Iraqi Freedom troop population. Ophthal Plastic Reconstruction Surgery. 23(5):397-9.

Bullock JD, Fleishman JA. (2007). Orbital cellulitis following dental extraction. Trans Am Ophthalmol Soc. 82:111-33.

Ganesh  A. Venugopalan. P. (2000). Preseptal orbital cellulitis following oral trauma. J Pediatr Ophthalmol Strabismus; 37:315.

Hutcheson KA. (2007). Periocular abscess and cellulitis from Pasteurella multocida in a healthy child. Am J Ophthalmol; 128:514.

Karkos P. Karagama Y, Karkanevatos A. Srinivasan, V. (2007). Recurrent periorbital cellulitis in a child. A random event or an underlying anatomical abnormality?. Int J Pediatr Otorhinolaryngol; 68:1529.

The Merck Manual (2009): preseptal and orbital cellulitis. Retrieve on 10^th Dec from www.merck.com/mmpe/sec09/ch108/ch108d.html

Raja, NS, Singh, NN. (2005). Bilateral orbital cellulitis due to Staphylococcus aureus: a previously unreported case. J Med Microbiol; 54:609.

Sorin A. April, MM, Ward, RF. (2006). Recurrent periorbital cellulitis: an unusual clinical entity. Otolaryngol Head Neck Surg; 134:153.