Acute pharyngitis presents with the symptoms; fever, sore throat, headache, tonsilar exudates, red posterior pharynx and many swollen and tender cervical lymph nodes (Harari et al, 2009; Fox et al, 2006; Bisno et al, 2002). The 6 year old boy has these symptoms thus, indicating a sore throat infection. The infectious agent needs to be determined from his clinical history, epidemiological features and subsequent confirmation with appropriate laboratory tests.
The 6 year old boy is also of school age or he maybe attending a day care which are places where acute pharyngitis can be contacted easily when in close proximity with the airborne droplets of a person infected. He may also have contacted it from a family member who is infected as according to Bisno et al, (2002), there is a 40% chance of contacting acute pharyngitis from an infected member of the family.
From the boys’ history, he had been in good health prior to the symptoms in late September and is thus, immunocompetent and the disease therefore had a sudden onset. According to Carey, Schuster and McGowan (2008), there are two major causes of pharyngitis in an immunocompetent patient:
· Viral and,
· Bacteria.
This thus rules out fungi as the infectious agent in this patient.
According to Fox et al (2006), sore throats tend to present in patients in autumn and winter period. As the patient presented with his symptoms in late September which is part of the autumn period, this further suggests that he may have sore throat. Fox et al (2006) further stated that group A β-hemolytic streptococcus (GABHS) is the most important causative agent of sore throat and that this bacteria is responsible for approximately one-third of sore throats in children of 5 to 15 years. It is therefore highly likely that he has GABHS as his age falls within this range.
A clinical diagnosis of acute sore throat resulting from GABHS as according to Bisno et al, (2002) can be made using the ‘sore throat decision rule’. This involves looking out for 4 symptoms. They are:
throat exudates,
enlarged sub-mandibular glands,
fever, and
absence of runny nose and cough.
If;
0 or 1 of the above sign/symptom is present in the patient then, GABHS is unlikely.
2 of the above signs/symptoms are present in the patient then, diagnosis is uncertain and further laboratory testing should be considered.
3 or 4 of the above signs/symptoms are present in the patient then, GABHS is likely.
When this rule is used it identifies most patients needing treatment and thus decreases antibiotic use for the treatment of sore throat by approximately 80% (Bisno et al, 2002).
The patient has 4 of the above signs/symptoms thus GABHS is likely.
The above is further supported by Carey, Schuster and McGowan (2008) as they stated that clinical clues to ascertain infection by Streptococcus Pyogenes are;
· the age of the patient as Strep throat usually occurs in young children of school-age
· absence of a cold symptoms and runny nose indicating a probable strep throat infection as opposed to a viral on, and
· Presence of classic signs and also symptoms of S. pyogenes pharyngitis which are; tonsillar exudates, fever, cervical lymphadenopathy with absence of cough.
Chamberlain (2010) stated that clinical and epidemiological factors must be looked at for appropriate diagnosis. Table 1 below shows the clinical and epidemiological factors to be considered as they are suggest bacterial causative agent if present in a patient. Almost all these factors are signs and symptoms as well as epidemiological factors in the 6 year old boy and thus, suggest bacterial etiology i.e. S pyogenes as the infectious agent.
TABLE 1: Clinical and Epidemiologic Findings Useful in the Diagnosis of PharyngitisEpidemiologic findings suggestive of Streptococcus pyogenes as the etiologic agent|
Patient aged 5–15 years
Presentation in winter or early spring
History of exposure
Sudden onset of signs and symptoms
Clinical findings suggestive of Streptococcus pyogenes as the etiologic agent
Sore throat
Fever
Headache
Nausea, vomiting, and abdominal pain
Inflammation of pharynx and tonsils
Patchy discrete exudate
Tender, enlarged anterior cervical nodes
Features suggestive of a virus as the etiologic agent
Conjunctivitis
Coryza
Cough
Diarrhea
Note: These findings, either individually or collectively, cannot definitively predict the presence of S pyogenes pharyngitis. They can identify persons with a high probability of being diagnosed with S pyogenes pharyngitis (and for whom throat culture or rapid antigen detection testing is indicated) or a low probability of S pyogenes pharyngitis (neither culture nor rapid antigen detection testing is necessary).
Source: http://www.atsu.edu/faculty/chamberlain/Website/lectures/lecture/uriphyn.htm When commenting on epidemiological features, Bisno et al (2002) further contended that the when age of a patient falls between 5-15 years, no child abuse or travel, GABHS should be highly suspected as the causative agent. The patient fits this description and it can thus be said that he has acute pharyngitis caused by GABHS.
According to Chamberlain (2010), any delay in treating S pyogenes pharyngitis over 9 days after symptoms have begun makes the patient to be at a risk of developing rheumatic fever and also suppurative complications. Thus, strategies must be used to appropriately diagnose the infectious agent causing acute pharyngitis as they will require antimicrobial therapy and hence unnecessary treatment of patients who are diagnosed with acute pharyngitis of viral origin is avoided (Chamberlain, 2010). Two methods are used for this diagnosis:
Rapid strep test and,
2. Throat culture (Kim, 2009)
1. Rapid strep test.
A swab from both tonsils and posterior pharyngeal area from the patient is collected to test for by detecting group A–specific carbohydrate N-acetylglucosamine. Sensitivity of this test varies but the specificity is superb if compared to culture with a range of 95–100% generally (Kim, 2009; Bisno et al 2002). Thus, a positive antigen test indicates GAS and therefore, a throat culture confirmation is neither needed nor necessary. However, confirmation must be carried out with a throat culture if the antigen test is negative (Kim, 2009).
2. Throat culture. A swab is taken from the same places as is taken for the rapid antigen test. The specimen is grown on agar blood plates. If GABHS is the etiologic agents, there would be b-hemolytic colonies which are catalase-negative, are gram-positive cocci and also exhibit sensitivity to Bacitracin (Chamberlain, 2010). This test is more sensitive than the rapid antigen test. Though the rapid test is readily available in the Doctors’ office and takes 5 to 10 minutes to perform, the throat culture takes 48 hours to complete thus, leading to the use of the rapid antigen tests more often (Chamberlain, 2010).
It follows that, if the rapid antigen detection test is positive, the throat culture is not required and thus treatment should commence with antibiotics e.g. penicillin. However, if rapid antigen detection test result is negative, a throat culture needs to be carried out (Chamberlain, 2010; Kim, 2009).
CONCLUSION
From the clinical and epidemiological data, it can be said that the 6 year old boy has acute pharyngitis. Though, it has also been seen that clinical and epidemiological factors must be taken into account with a follow up of the appropriate laboratory test for the accurate diagnosis of acute pharyngitis.
REFERENCES
Bisno, A. L., Gerber, M. A., Gwaltney, J. M. Jr., Kaplan, E. L. and Schwartz, R. H. (2002) 'Practice guidelines for the diagnosis and management of group A streptococcal pharyngitis.' Clinical infectious disease, 35(2), 113-25.
Fox, J. W., Marcon, M. J. and Bonsu, B. K. (2006) ‘Diagnosis of Streptococcal Pharyngitis by detection of Streptococcus Pyogenes in posterior pharyngeal versus oral cavity Specimens.’ Journal of Clinical Microbiology, 2593-2594.
Harari, B. L., Darenberg, J., Neal S., Siljander, T., Strakova, L., Tanna, A., Ekelund, C. R. K., Koliou, M., Tassios, P.T., Van der Linden, M., Straut, M., Vuopio-Varkila, J., Bouvet, A., Efstratiou, A., Schale´n, C., Henriques-Normark, B., the Strep-EURO study group and Jasir, A. (2009) ‘Clinical and microbiological characteristics of severe Streptococcus pyogenes Disease in Europe.’ Journal of clinical microbiology, 47(4), 1155–1165.
Kim, S. (2009) ‘The evaluation of SD bioline Strep A rapid antigen test in Acute Pharyngitis in paediatric Clinics.’ Korean J Lab Med., 29:320-3.
Name: Sylvia C. N. Igboanugo
ID: 000486591
CLINICAL ASPECT OF ACUTE PHARYNGITIS
Acute pharyngitis presents with the symptoms; fever, sore throat, headache, tonsilar exudates, red posterior pharynx and many swollen and tender cervical lymph nodes (Harari et al, 2009; Fox et al, 2006; Bisno et al, 2002). The 6 year old boy has these symptoms thus, indicating a sore throat infection. The infectious agent needs to be determined from his clinical history, epidemiological features and subsequent confirmation with appropriate laboratory tests.The 6 year old boy is also of school age or he maybe attending a day care which are places where acute pharyngitis can be contacted easily when in close proximity with the airborne droplets of a person infected. He may also have contacted it from a family member who is infected as according to Bisno et al, (2002), there is a 40% chance of contacting acute pharyngitis from an infected member of the family.
From the boys’ history, he had been in good health prior to the symptoms in late September and is thus, immunocompetent and the disease therefore had a sudden onset. According to Carey, Schuster and McGowan (2008), there are two major causes of pharyngitis in an immunocompetent patient:
· Viral and,
· Bacteria.
This thus rules out fungi as the infectious agent in this patient.
According to Fox et al (2006), sore throats tend to present in patients in autumn and winter period. As the patient presented with his symptoms in late September which is part of the autumn period, this further suggests that he may have sore throat. Fox et al (2006) further stated that group A β-hemolytic streptococcus (GABHS) is the most important causative agent of sore throat and that this bacteria is responsible for approximately one-third of sore throats in children of 5 to 15 years. It is therefore highly likely that he has GABHS as his age falls within this range.
A clinical diagnosis of acute sore throat resulting from GABHS as according to Bisno et al, (2002) can be made using the ‘sore throat decision rule’. This involves looking out for 4 symptoms. They are:
If;
When this rule is used it identifies most patients needing treatment and thus decreases antibiotic use for the treatment of sore throat by approximately 80% (Bisno et al, 2002).
The patient has 4 of the above signs/symptoms thus GABHS is likely.
The above is further supported by Carey, Schuster and McGowan (2008) as they stated that clinical clues to ascertain infection by Streptococcus Pyogenes are;
· the age of the patient as Strep throat usually occurs in young children of school-age
· absence of a cold symptoms and runny nose indicating a probable strep throat infection as opposed to a viral on, and
· Presence of classic signs and also symptoms of S. pyogenes pharyngitis which are; tonsillar exudates, fever, cervical lymphadenopathy with absence of cough.
Chamberlain (2010) stated that clinical and epidemiological factors must be looked at for appropriate diagnosis. Table 1 below shows the clinical and epidemiological factors to be considered as they are suggest bacterial causative agent if present in a patient. Almost all these factors are signs and symptoms as well as epidemiological factors in the 6 year old boy and thus, suggest bacterial etiology i.e. S pyogenes as the infectious agent.
TABLE 1: Clinical and Epidemiologic Findings Useful in the Diagnosis of Pharyngitis Epidemiologic findings suggestive of Streptococcus pyogenes as the etiologic agent|
Source: http://www.atsu.edu/faculty/chamberlain/Website/lectures/lecture/uriphyn.htm
When commenting on epidemiological features, Bisno et al (2002) further contended that the when age of a patient falls between 5-15 years, no child abuse or travel, GABHS should be highly suspected as the causative agent. The patient fits this description and it can thus be said that he has acute pharyngitis caused by GABHS.
According to Chamberlain (2010), any delay in treating S pyogenes pharyngitis over 9 days after symptoms have begun makes the patient to be at a risk of developing rheumatic fever and also suppurative complications. Thus, strategies must be used to appropriately diagnose the infectious agent causing acute pharyngitis as they will require antimicrobial therapy and hence unnecessary treatment of patients who are diagnosed with acute pharyngitis of viral origin is avoided (Chamberlain, 2010). Two methods are used for this diagnosis:
- Rapid strep test and,
2. Throat culture (Kim, 2009)- 1. Rapid strep test.
A swab from both tonsils and posterior pharyngeal area from the patient is collected to test for by detecting group A–specific carbohydrate N-acetylglucosamine. Sensitivity of this test varies but the specificity is superb if compared to culture with a range of 95–100% generally (Kim, 2009; Bisno et al 2002). Thus, a positive antigen test indicates GAS and therefore, a throat culture confirmation is neither needed nor necessary. However, confirmation must be carried out with a throat culture if the antigen test is negative (Kim, 2009).2. Throat culture.
A swab is taken from the same places as is taken for the rapid antigen test. The specimen is grown on agar blood plates. If GABHS is the etiologic agents, there would be b-hemolytic colonies which are catalase-negative, are gram-positive cocci and also exhibit sensitivity to Bacitracin (Chamberlain, 2010). This test is more sensitive than the rapid antigen test. Though the rapid test is readily available in the Doctors’ office and takes 5 to 10 minutes to perform, the throat culture takes 48 hours to complete thus, leading to the use of the rapid antigen tests more often (Chamberlain, 2010).
It follows that, if the rapid antigen detection test is positive, the throat culture is not required and thus treatment should commence with antibiotics e.g. penicillin. However, if rapid antigen detection test result is negative, a throat culture needs to be carried out (Chamberlain, 2010; Kim, 2009).
CONCLUSION
From the clinical and epidemiological data, it can be said that the 6 year old boy has acute pharyngitis. Though, it has also been seen that clinical and epidemiological factors must be taken into account with a follow up of the appropriate laboratory test for the accurate diagnosis of acute pharyngitis.
REFERENCES
Bisno, A. L., Gerber, M. A., Gwaltney, J. M. Jr., Kaplan, E. L. and Schwartz, R. H. (2002) 'Practice guidelines for the diagnosis and management of group A streptococcal pharyngitis.' Clinical infectious disease, 35(2), 113-25.
Chamberlain, N. R. (2010) Infections of the upper respiratory tract. Avaliable at: http://www.atsu.edu/faculty/chamberlain/Website/lectures/lecture/uriphyn.htm (Accessed: 17th December 2010).
Fox, J. W., Marcon, M. J. and Bonsu, B. K. (2006) ‘Diagnosis of Streptococcal Pharyngitis by detection of Streptococcus Pyogenes in posterior pharyngeal versus oral cavity Specimens.’ Journal of Clinical Microbiology, 2593-2594.
Harari, B. L., Darenberg, J., Neal S., Siljander, T., Strakova, L., Tanna, A., Ekelund, C. R. K., Koliou, M., Tassios, P.T., Van der Linden, M., Straut, M., Vuopio-Varkila, J., Bouvet, A., Efstratiou, A., Schale´n, C., Henriques-Normark, B., the Strep-EURO study group and Jasir, A. (2009) ‘Clinical and microbiological characteristics of severe Streptococcus pyogenes Disease in Europe.’ Journal of clinical microbiology, 47(4), 1155–1165.
Kim, S. (2009) ‘The evaluation of SD bioline Strep A rapid antigen test in Acute Pharyngitis in paediatric Clinics.’ Korean J Lab Med., 29:320-3.