A combination of history, clinical manifestations, and laboratory findings is required to distinguish a viral genesis of acute angina tonsillaris from bacterial causes. The Centor and McIsaac criteria are a useful diagnostic tool in this regard. Regarding treatment options, the pros and cons of using antibiotics should be carefully weighed.
Inflammation of the palatine tonsils (angina tonsillaris) is a common clinical picture. Acute tonsillitis is mostly caused by viral pathogens, less frequently by bacterial pathogens. A common viral form is Pfeiffer’s glandular fever, which is caused by the Epstein-Barr virus (EBV) and is also known as infectious mononucleosis or EBV tonsillitis. In addition to tonsil infection, this may involve other lymphoid organs such as the liver and spleen. The main pathogens of acute bacterial tonsillitis are Streptococcus pyogenes [1]. Infectious mononucleosis is very common worldwide.
Lymphocyte-Leukocyte Index is very informative
In the case of EBV-associated genesis, the classic symptom triad of tonsillopharyngitis, fever, and cervical lymph node swelling is present in 98% of affected patients [1]. According to the s2k guideline, in contrast to streptococcal tonsillitis, viral causes tend to present with two-dimensional rather than stipple-like coatings on the tonsils [1]. In addition, cervical lymph node swelling is palpable not only anterior to the sternocleidomastoid muscle but usually posterior to it as well. On an immunopathologic level, viral tonsillitis is typically associated with a lymphocytic inflammatory response, whereas bacterial tonsillitis is associated with granulocytic inflammation [1]. The diagnostic procedure includes clinical inspection, EBV serology, lymphocyte-leukocyte index, and smear, possibly including a Streptococcus A rapid test. Determining the lymphocyte-leukocyte index is a very informative method, explains Nikos Kastrinidis, MD, senior physician at the Department of Ear, Nose, Throat and Facial Surgery at the University Hospital Zurich [2]. If the ratio of the number of lymphocytes to the number of leukocytes >is 0.35, the diagnosis of glandular fever can be made with 90% sensitivity and 100% specificity. A bacterial smear is useful in cases that are unclear and resistant to therapy. In cases of suspected or confirmed EBV infection, symptomatic treatment including physical rest, hydration, analgesia, and antipyresis is recommended. The s2k guideline suggests ibuprofen and paracetamol as non-steroidal analgesic anti-inflammatory drugs (NSAIDs). Regarding acetaminophen, which is contraindicated in hepatic damage, Dr. Kastrinidis points out that the infection often affects the liver as well, so liver tests should be routinely obtained [2,3]. As a further diagnostic clarification, an ultrasound of the abdomen is useful in the case of a severe course, to rule out splenic hyperplasia.
In which cases prescribe antibiotics?
Streptococcal angina usually has a benign course with spontaneous improvement within a week, and antibiotics are not always needed, Dr. Kastrinidis said. If antibiotics are used, this could also be delayed, for example, if symptoms worsen or do not improve within 72 hours. A review article on the question in which cases antibiotic treatment is useful was published last year [4]. The Centor criteria and the McIsaac criteria can be informative in assessing whether or not streptococcus-positive angina, i.e. bacterial tonsillitis, is present (Fig. 1) . A score can be calculated which indicates the probability that a streptococcus-positive finding will be detected in a smear. The authors of the review article suggest treatment with antibiotics (e.g. penicillin) depending on the patient’s condition or if the symptoms worsen at a value of >2 in the Centor score or McIsaac score. Dr. Kastrinidis points out that affected individuals very often reach this cut-off value, and in these cases, detection of potentially tonsillo-pathogenic bacteria by bacterial culture or rapid test is useful to confirm the diagnosis [2]. If this cut-off value is less than 2, a smear may be misleading because several hundred different bacterial species and viruses are present in the ear, nose, and throat and it may be difficult to clearly differentiate between commensal and (potentially) pathogenic germs [1].
The benefits of antibiotic therapy should be carefully weighed against potential disadvantages, particularly side effects and the risk of bacterial resistance development [1]. If antibiotic treatment is chosen, amoxicillin and ampicillin should be avoided because of the high risk of drug exanthema; clindamycin (Dalacin®) can be used instead [1,2]. With adequate therapy, most patients are symptom-free after less than 48 hours. If this is not the case, therapy compliance and diagnosis should be reviewed. A throat swab after cessation of antibiotic therapy is only useful in patients with risk factors (e.g., acute rheumatic fever in the medical history)
Literature:
- S2k Guideline 017/024: Therapy of inflammatory diseases of the palatine tonsils – tonsillitis, www.awmf.org
- Kastrinidis N: The management of common ENT disorders in family practice. Nikos Kastrinidis, MD. FOMF 5/13-16/2020, Livestream.
- Swiss Drug Compendium, www.compendium.ch
- Hofmann Y, et al: Time for a paradigm shift. Treatment of streptococcal angina. Swiss Med Forum 2019; 19(2930): 481-488.
HAUSARZT PRAXIS 2020; 15(10): 55-56
