What is Retropharyngeal Abscess: Causes, Symptoms, Treatment, Recovery, Prognosis, Complication

A retropharyngeal abscess is medical situation where there is a pus (abscess) formation in the tissue located on the back of the patients’ throat. Retropharyngeal abscess is generally caused during throat infection as an after effect of throat infection. It is commonly seen in the small children below age of five. However, retropharyngeal abscess can affect an individual from any age group. In the worst case, retropharyngeal abscess can lead to blockage of air passage to the lungs and can get life threatening.

The common symptoms of retropharyngeal abscess are fever, stridor, sore throat and stiff neck. The cases of retropharyngeal abscess have significantly reduced in the present scenario because of the availability of effective antibiotics, which can prevent respiratory infections from getting worse. The incidences of RPA are particularly growing in the United States.

Peritonsillar Abscess is a very similar medical condition in which there is pus formation in the tonsils located at the back of the mouth. On the other side, in retropharyngeal abscess, the puss formation occurs in the lymph nodes on the back of the throat. The puss formation is caused due to bacterial infection in tissue. Tonsils are actually the lymph tissue and are very important part of immune system very much like lymph node.

Strep or Group A Streptococci is a type of bacteria present in mouth which is responsible for peritonsillar abscesses. There are also some other bacteria which can cause peritonsillar abscesses. The same bacteria along with another type of bacteria called “staph” or Staphylococcus bacteria also cause retropharyngeal abscess. In case of peritonsillar abscesses, the infection compulsorily starts from throat whereas in retropharyngeal abscess, the infection may start from throat, teeth or even from a trauma (such as a laceration or cut in the throat).

What are Some Possible Complications of Peritonsillar Abscess and Retropharyngeal Abscess?

Both the medical cases peritonsillar abscess and retropharyngeal abscess have almost similar complications in which the airway may get chocked making it very hard to breath. In some cases the infection can also affect the surrounding area.

Retropharyngeal abscess is mostly seen in small children that make it harder to suspect in case of adults. As the cases of retropharyngeal abscess are very smaller, it is hard for emergency physicians to diagnose the case of retropharyngeal abscess. In addition, the signs and symptoms of retropharyngeal abscess are not very specific.

• The cases of retropharyngeal abscess are more commonly reported in males as compared to females.
• For a long time, it was considered that retropharyngeal abscess affects only small children but recently many cases of retropharyngeal abscess in adults have been seen.
• It is necessary to detect the case of retropharyngeal abscess early as delay can lead to complications and even life threatening condition for the patient.

The occurrence of retropharyngeal abscess in most cases is an after effect of the infection in mouth or contiguous spread in the upper respiratory tract or any lymphatic drainage.

In some cases, retropharyngeal abscess may also occur as a result of foreign body removal, nasogastric tube insertion, endotracheal intubation or endoscopy.

The individuals who are chronically ill (immune compromised) which generally include patients of cancer, AIDS, diabetes, alcoholism etc… are more prone to retropharyngeal abscess.

Recent studies in USA shows that inpatients of peritonsillar abscess have a very high risk of retropharyngeal abscess. On the basis of the data collected by the National (Nationwide) inpatient sample, it is seen that there is a significant rise in the cases of adults’ concurrently developing peritonsillar abscess and retropharyngeal abscess. Earlier in 2003 only about 0.5 percent of the adult patients of peritonsillar abscess got affected with retropharyngeal abscess that rose to 1.4 percent by 2010. The detailed analysis of the figures also suggests that the patients of peritonsillar abscess with age 40 or higher are even more at risk of developing retropharyngeal abscess.

The organisms responsible for the occurrence of retropharyngeal abscess are generally anaerobes, aerobes and gram-negative organisms in some cases. However, methicillin-resistant Staphylococcus aureus (MRSA) is increasing reported to be the organisms causing retropharyngeal abscess in the recent cases.

Following is the list of organisms responsible for retropharyngeal abscess in adults:

• Staphylococcus epidermidis
• Beta-hemolytic streptococci
• Klebsiellapneumoniae
• Pseudomonas aeruginosa
• Cryptococcus neoformans
• Streptococcus viridans
• Peptostreptococcus species
• Extended-spectrum beta-lactamase (ESBL) – producing Enterobacteriaceae
• Fusobacterium species
• Eikenellacorrodens
• Methicillin-resistant Staphylococcus aureus ( MRSA)
• Bartonellahenselae
• Anaerobic streptococci
• S aureus
• Actinomycetes
• Mycobacterium tuberculosis
• Escherichia coli
• Prevotella species
• Bacteroides species.

Following is the list of organisms causing retropharyngeal abscess in case of children:

• Beta-hemolytic streptococcus (Streptococcuspyogenes).
• S aureus
• Peptostreptococcus species
• Haemophilus species
• Veillonella species
• Bacteroides species
• Staphylococcus coagulase negative
• Brucella species
• Fusobacterium species
• Prevotella species
• MRSA (Methicillin-resistant Staphylococcus aureus.)

Following is the list of common signs and symptoms of retropharyngeal abscess:

• Neck pain, stiff neck, presence of swelling in the neck is the most common symptoms of retropharyngeal abscess.
• Dribbling of saliva; uncontrollable flow of saliva from the mouth is another sign of retropharyngeal abscess.
• Dysphagia; difficulty in swallowing is also seen in retropharyngeal abscess.
• Malaise, which is general discomfort and uneasiness.
• Airways obstruction is a symptom of retropharyngeal abscess.
• Trismus, where patients open their mouth with huge difficulty.
• Severe sore throat.
• Stridor and other related respiratory problems, like high-pitch of breathing sound takes place abnormally is another symptom of retropharyngeal abscess.
• Cough.
• Agitation.
• Pus accumulation in the space around the tissues, at the back of the throat.
• Fever with very high temperature.

It is strongly recommended to refer to a doctor immediately for retropharyngeal abscess in case of occurrence of any of the above symptoms.

Following are some of the factors that may increase the risk of retropharyngeal abscess:

• Retropharyngeal abscess is more likely to occur in case of the following infections:

  • Tonsillitis – Infection and swelling of the tonsils is a major risk factor for retropharyngeal abscess.
  • Pharyngitis – Inflammation of the throat and also otitis media which is a middle ear infection are risk factors for retropharyngeal abscess.
  • Scarlet fever – Sore throat with rashes caused by the bacterium streptococcus pyogenes
  • Peritonsillitis – Inflammation of the peritonsillar tissues
  • Measles is also a possible factor of risk for retropharyngeal abscess.
• Any case of damage to body by foreign body like pieces of bones, and pins.
• The children in the age group of below 5 years are at higher risk of retropharyngeal abscess.

The risk factors only suggests that in the above cases, the risk of developing retropharyngeal abscess increases and it does not necessarily mean that retropharyngeal abscess will occur definitely. Retropharyngeal abscess can also occur in individuals without any of the risk factors mentioned above. Thus, risks factors are merely increase the possibility and do not necessarily result in developing retropharyngeal abscess. Some of the risk factors are more crucial.

Following is the list of complications that may arise in case of retropharyngeal abscess:

• Obstruction in the pathway, which carries air to lungs leading to problem in breathing, could be a major complication in retropharyngeal abscess.
• Aspiration pneumonia can also be a complication in retropharyngeal abscess. The infection causes by retropharyngeal abscess may spread to lungs and airways causing Inflammation/infection.
• Mediastinitis which is a feeling of inflammation in the tissues of the mid-chest is a complication in retropharyngeal abscess.
• Osteomyelitis is a complication in retropharyngeal abscess. Infections caused by bacteria and other germs in the bone.
• Pericarditis is also a complication in retropharyngeal abscess: Feeling of inflammation in the tissues present around the heart.
• Epidural abscess where there is pus formation in the region between the spinal cord and brain in the situation is a possible complication.
• Septicemia, which is situation in which bloodstream is affected by bacteria leading to severe infection.
• Adult respiratory distress syndrome in which the air sacs of the lungs get filled up by fluids causing severe infection.
• The infection may sometimes spread around and degrade the 2nd and 3rd cervical vertebrae on the surrounding.
• It may also affect a special vein present in the neck called as jugular vein leading to septic thrombosis.

However, with proper care and timely treatment, the complications of retropharyngeal abscess can be easily avoided and patient can recover from retropharyngeal abscess quickly.

The primary test for the retropharyngeal abscess involves a physical examination of the throat followed by the collection and analyses of the throat culture. Throat culture is a sample of tissue collected from the back of the throat with the help of a cotton swab for examination.

Following are some of the common tests for diagnosing retropharyngeal abscess:

• Physical examination and evaluation of medical history for retropharyngeal abscess, where the doctor examines the throat to look for signs of infection
• Throat culture for retropharyngeal abscess which involves collection of a pus sample from the back of the throat by rubbing it with a cotton swab. The sample is closely examined in the labs to identify the growth of specific microorganisms.
• Some tests also involve use of x-rays and CT scan to create images of the neck for the diagnoses of retropharyngeal abscess.
• Complete blood count (CBC) to look for the increase in count of white blood cells which is indication of infection.

The signs and symptoms of retropharyngeal abscess share similarities with some other clinical conditions and thus it may be necessary to perform some other tests to be definite about the case of retropharyngeal abscess.

The treatment of retropharyngeal abscess involves a simple surgery in which the surgeon removes the puss to avoid infection getting worse and causing blockage in the airway. However, surgery for retropharyngeal abscess is performed only if it is necessary. In other cases, the doctor normally prescribes corticosteroids, which are very effective in reducing swelling and inflammation. Some doctors also prescribe intravenous (IV) high-dose antibiotics to suppress the throat infection.

In the early stages of retropharyngeal abscess treatment, doctors try medical treatments to control the situation. If the treatment does not work, the doctor would consult with otolaryngologist to go for surgery to treat retropharyngeal abscess. It is necessary to safeguard the airway in case of treatment of retropharyngeal abscess as it can be blocked and thus surgical methods may be necessary. The mode of treatment is subject to the patient’s condition and severity of respiratory distress.

1. Airway Compromise in Retropharyngeal Abscess

   If it is suspected that airway is being chocked or compromised due to retropharyngeal abscess that are indicated by signs like stridor, decreased oxygen saturation as the patient becomes fatigued and tachypnoea, the patient needs immediate medical attention and must be admitted in a nearby hospital. The doctors generally use antibiotics and corticosteroids as the primary step to control infection. If that proves to be ineffective, the patient is examined under anaesthesia (EUA) for the case of surgery for . Surgery involves insertion of a surgical airway like tracheostomy or intubation to enable the patient to breathe properly. An adult anaesthetist for adults and pediatric anaesthetist for children to ensure safety should always perform the surgery.

   Fiber-optic is generally preferred for intubation as it provides a good view of the airway to the doctor and also makes sure that abscess does not burst out. The uncuffed tube is especially advantageous for the surgeon as it allows the good view of the posterior pharyngeal wall by inserting a pack, which helps in the surgery.

   If the case of retropharyngeal abscess is confirmed on examination by appearance of bulge on the posterior oropharyngeal wall or by aspiration of purulent fluid, the surgery for retropharyngeal abscess is immediately performed by making a transoral incision and allowing the puss to drain out. In some particular cases where retropharyngeal abscess is found to spread to posterior mediastinum, it is necessary to drain out the purulent discharge and debridement of necrotic material immediately from the affected pleural space and pericardial area.

   In a few cases where the airway may not show any signs of improvement even after surgery, the patient must be taken to ICU for proper care and empirical intravenous antibiotics must be started immediately for retropharyngeal abscess. In addition, intubation must be continued. Even for the patients with successful surgery and stable airway, empirical intravenous antibiotic therapy is recommended as the follow up treatment.

2. No Airway Compromise in Retropharyngeal Abscess

   Even in the case of retropharyngeal abscess where airway is not compromised, it is necessary to admit the patient in hospital. Once it is ensured that airway is working properly and there are no signs of mediastinal extension, empirical intravenous antibiotics therapy must be implemented immediately and must be continued for 24-48 hours. In some cases, doctors prefer to use corticosteroids along with intravenous antibiotics. The patient is then observed under the CT scan. In the case of fortunate patients where the retropharyngeal abscess is in early stage and there is only the formation of cellulitis and no abscess, the intravenous antibiotics treatment with or without corticosteroids is sufficient and no surgery is required.

   However if the patients shows no signs of improvement indicated by continuing swinging pyrexia and deterioration of vital organs, surgical methods for retropharyngeal abscess are required to drain out the abscess. Before surgery for retropharyngeal abscess, the condition of the patient in view of progress of the abscess is analyzed with the aid of CT scan. For CT scan, anesthesia is injected in case of children whereas in case of adults, it may or may not be necessary. Even after the drainage of progress of the abscess via surgery for retropharyngeal abscess, intravenous antibiotics surgery is recommended as an empirical regimen and should be continued.

Antibiotics are effective against most of the following organisms which are mainly responsible for retropharyngeal abscess: Streptococcus epidermidis, Streptococcus viridans, beta-haemolytic streptococci and Staphylococcus aureu. Some other organisms that can also cause retropharyngeal abscess are: Veillonella species, Haemophilus parainfluenzae, Bacteroides melaninogenicus, and Klebsiella pneumoniae. However both the categories of organisms can cause retropharyngeal abscess and can cause serious respiratory problems and infection.

Commonly used antibiotics for the treatment of retropharyngeal abscess are as follows: cefuroxime clindamycin, ampicillin/sulbactam, ceftriaxone, metronidazole, and amoxicillin/clavulanic acid. The above listed antibiotics are used in combination to be effective against the organisms causing retropharyngeal abscess. E.g. Clindamycin plus cefuroxime or ceftriaxone plus metronidazole. Metronidazole is especially effective against the anaerobic bacteria possibly because of some connection with the parapharyngeal space which is related to the oral cavity.

The empirical antibiotic therapy should show signs of improvement in just 24-48 hours and in case of any delay, revaluation of the patient and the treatment is necessary.
Clinical improvement should be seen within 24 to 48 hours; if this is not the case, the patient should be re-evaluated. The antibiotic spectrum may need to be broadened. In extreme cases where the antibiotics are ineffective retropharyngeal abscess may be caused by mycobacteria or MRSA. It is recommended to complete a full 14 days course of empirical antibiotics therapy until the patient feels any symptoms of fever or face any difficulty in taking medicines. In such cases, the patient may be recommended target therapy on the basis of the examination of culture.

It is important that the airway is checked regularly for complications during the course of treatment for retropharyngeal abscess. Sufficient nutrition and intravenous hydration should be given to patients of retropharyngeal abscess as long as they are able to take food and drinks without any problem. In case of some patients with retropharyngeal abscess, analgesia may be required. Patients must not ignore any signs or symptoms and share it with the doctor immediately.

Antibiotic therapy is an effective treatment for retropharyngeal abscess and can be reliably used as an alternative treatment for surgery in case of non-complicated retropharyngeal abscess.

It can be very tough for the patient of retropharyngeal abscess to cope with the situation. Retropharyngeal abscess directly affects mouth which plays a vital role in our routine and living as it helps in breathing, talking and eating and thus it can get even harder for the patient. Apart from these problems, the treatment can cause more stress. Here are some ways to cope up:

• Learn enough about retropharyngeal abscess to make treatment decisions. Prepare yourself well before the appointment with the doctor by listing down your queries you want to resolve. Talk to your doctor and about the disease and try to gather more information from various sources. It is always good to be aware of your disease as it can make you feel confident and help you take decisions about the treatment.
• Find someone to talk about retropharyngeal abscess coping. Having someone to share your problems and talk about your situation is always helpful. Try to be in close touch with your friends and family members, especially with someone who can listen to your problems with patience. Apart from family and friends, you can also talk to counselors or clergy member. Also there are many support groups that you can join.
• Take care of yourself during retropharyngeal abscess treatment. The disease of retropharyngeal abscess can make affect you both mentally and physically. Thus it is very important to stay healthy and free from stress. Take good sleep at night and make a habit of walking and exercising regularly preferably in morning. Keep your mind relaxed by engaging yourself in hobbies and activities like reading books, listening to music etc…

The recovery period/ healing time for retropharyngeal abscess is not fixed and might vary according to the mode of treatment for retropharyngeal abscess. Thus, refer to your doctor to get precise information related to recovery period or for any other queries related to treatment.

The prognosis for retropharyngeal abscess is generally good if there are no severe complications. The prediction about the treatment and recovery related to retropharyngeal abscess largely depends upon the severity of the infection. Generally, in simple cases of retropharyngeal abscess in healthy patients, recovery is excellent without any risk of repetition. However, in complex cases of retropharyngeal abscess, there is high uncertainty and risk of mortality and morbidity.

If the patient of retropharyngeal abscess is found with any symptoms of airway compromise during examination, he /she must be immediately attended and treated without any delay. Further, an otolaryngologist must examine the patient. Sever infection can affect larger area with lot of pus which can cause compression of windpipe (pharynx or trachea) leading to problem in breathing. In worst cases, it can even result in aspiration or asphyxiation and pneumonia.

Proper care must be taken in case of airway compromise to keep the body in proper position and avoid unwanted movements. In addition, the patient of retropharyngeal abscess must not leave the acute area until the doctor assures sufficient recovery and stability.

The use of any type of sedatives and paralytics can be dangerous must be avoided as it can sedate the muscles of airway which can alleviate the problem in breathing. Endotracheal intubation should be avoided as it can be dangerous if the doctor does not have a direct view of the infected area. In such cases, fiber optic intubation can be used as an alternative. Surgical methods like cricothyroidotomy or tracheotomy can also be used if necessary.

In some cases, the infection from the throat can get widespread and affect the tissues on the surrounding. It can be life threatening if not treated immediately especially if the infection spread to carotid artery and rupture it resulting into mortality in about 20 to 40 percent of the cases. The percentage further increases to 40 percent if the jugular vein gets infected leading to thrombosis of the jugular vein. Hence, it is critical to identify and treat the complication of retropharyngeal abscess immediately.

The infection in some cases of retropharyngeal abscess can also spread to spinal cord resulting into vertebral erosion and osteomyelitis. This can further lead to spinal cord injury or subluxation. In worst scenario of transverse ligament erosion, atlanto-occipital separation can also occur. There are also chances of retropharyngeal abscess getting into chest causing leading to mediastinitis, with a mortality rate of 40 to 50 percent.

Retropharyngeal abscess can be prevented by ensuring that the infection in the upper respiratory is timely treated and not allowed to spread.

• It is necessary to identify the symptoms of respiratory infections and start the treatment immediately to prevent the case of retropharyngeal abscess.
• Timely treatment of the infection can significantly reduce the chances of developing retropharyngeal abscess.