If a patient presents with a complaint of a sore throat, a number of differential diagnoses must be considered before determining a final diagnosis.  This paper considers three examples of potential diagnoses for this condition with an explanation of why such a diagnosis might be appropriate if other symptoms apply.  The three possible diagnoses for such a case considered in this paper are viral pharyngitis, bacterial pharyngitis, and tonsillitis.  It should be noted, however, that the single symptom of sore throat is quite non-specific and other diagnoses such as acid reflux, allergies or even tumors are also possible based on other symptoms or the results of clinical evaluation and blood work (Merriman, 2007).

Possibility #1: Viral Infection (Viral Pharyngitis)

Studies indicate that the majority of presentations for sore throat are the result of a viral infection (McIsaac, 1998; Merriman, 2007). Because viral pharyngitis is generally associated with an infection that involves other systems in the body, there may be additional symptoms such as fever, difficulty swallowing, pain in joints or muscles, and swollen lymph nodes (Vorvick & Zieve, 9 May 2010).  One such virus is the Epstein-Barr Virus (EBV) which causes infectious mononucleosis/glandular fever.  This condition usually includes additional symptoms such as fever, exudative pharyngitis, lympaenopathy, and atypical lymphocytosis (Simpson & Ivey, 2007).  Additional viral causes for the sore throat may include acute HIV infections. In the case of  acute HIV infections, additional symptoms generally include fever, fatigue, rash, and weight loss (Ibid.).

To distinguish viral infections from bacterial infections that may respond to antibiotics, throat swabs can be taken and cultured. Additional tests to check for EBV specifically may include nonspecific heterophil antibody testing and serological antibody testing for EBV; additional HIV antibody testing may be done, but even if that returns negative, positive virologic tests can confirm the diagnosis of acute HIV (Simpson & Ivey, 2007).

Antibiotics are not effective against viral pharyngitis. The recommended treatment for the pharyngitis beyond treatment for any overarching cause (i.e., mononucleosis, HIV, or other major viral infection)  is primarily symptomatic relief using gargling with warm water, over the counter pain relievers (acetaminophen or ibuprofen), and drinking cold liquids or popsicles to soothe the throat (Vorvick & Zieve, 9 May 2010).

Possibility #2: Bacterial Infection (Bacterial Pharyngitis), including Strep Throat

Bacterial agents that cause pharyngitis are commonly Group A streptococcus (GAS), but may be other types of bacteria.  GAS can also cause strep throat.  A rapid test throat swab can determine if strep throat is the cause of the sore throat. Generally, patients with bacterial pharyngitis do not have a runny nose, cough, or conjunctivitis associated with viral pharyngitis; instead, they may experience pharyngeal erythmea, tonsillar exudates, and anterior cervical lymphadenopathy which last for 7 to 10 days if no treatment is given (Perry, 2007).

The section of this paper below “Determining Use of Antibiotics when Presented with a “Sore Throat” Patient” provides guidance on how to determine whether an antibiotic should be prescribed. Regardless of the swab results, symptomatic relief can be gained by drinking warm honey or lemon tea, gargling with warm salt water, drinking cold liquids or popsicles, throat lozenges, using a humidifier to soothe dried throat tissues, and pain medications such as acetaminophen or ibuprophen; do not use aspirin, particularly with children (Vorvick & Zieve, 10 Jan. 2010).

Possibility #3: Tonsillitis

Tonsillitis is a possibility if infection (either bacterial or viral) overwhelms the tonsils so they swell and become infected themselves.  Additional symptoms that can help distinguish tonsillitis from other possible diagnoses include: difficulty swallowing; fever; reddened tonsils possibly with white spots (determined by visual inspection); sore throat that lasts longer than 48 hours; headache; and tenderness of the jaw or throat.  There may also be ear pain.  Further clinical tests may be done to distinguish this condition.  A rapid strep test using a throat swab can be done to distinguish this from strep throat.  Assuming strep is not indicated, a throat swab and culture can be done to determine if the cause for the swollen tonsils is bacterial or viral.  If the cause is bacterial, an antibiotic may be prescribed.  Other symptomatic relief can result from drinking cold liquids or popsicle; gargling with warm salt water; throat lozenges with benzocaine to reduce pain; and  pain medications such as acetaminophen or ibuprofen. Aspirin is not recommended for children because of the link to Reye syndrome (Kaneshiro & Zieve, 2010).