and spleen. Bacterial infections that cause tonsillitis can also cause a distinct "scarletiniform" rash, vomiting, and tonsillar spots or discharge. Tonsilloliths occur in up to 10% of the population frequently due to episodes of tonsillitis. Causes Viral infections cause 40 to 60% of cases of tonsillitis. Many viruses can cause inflammation of the tonsils (and the rest of throat) including adenovirus, rhinovirus, coronavirus, influenza virus, parainfluenza virus, coxsackievirus, measles virus, Epstein-Barr virus, cytomegalovirus, respiratory syncytial virus, and herpes simplex virus. Tonsillitis can also be part of the initial reaction to HIV infection. An estimated 1 to 10% of the cases are caused by Epstein-Barr virus. Tonsillitis can also stem from infection with bacteria, predominantly Group A β-hemolytic streptococci (GABHS), which causes strep throat. Bacterial infection of the tonsils usually follows the initial viral infection. When tonsillitis recurs after antibiotic treatment for streptococcus bacteria, it is usually due to the same bacteria as the first time, which suggests that the antibiotic treatment was not fully effective. Less common bacterial causes include: Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydia pneumoniae, Bordetella pertussis, Fusobacterium sp., Corynebacterium diphtheriae, Treponema pallidum, and Neisseria gonorrhoeae. Anaerobic bacteria have been implicated in tonsillitis, and a possible role in the acute inflammatory process is supported by several clinical and scientific observations. Sometimes tonsillitis is caused by an infection of spirochaeta and treponema, which is called Vincent's angina or Plaut-Vincent angina. Within the tonsils, white blood cells of the immune system destroy the viruses or bacteria by producing inflammatory cytokines like phospholipase A2, which also lead to fever. The infection may also be present in the throat and surrounding areas, causing inflammation of the pharynx. Diagnosis There is no firm distinction between a sore throat that is specifically tonsillitis and a sore throat caused by inflammation in both the tonsils and also nearby tissues. An acute sore throat may be diagnosed as tonsillitis, pharyngitis, or tonsillopharyngitis (also called pharyngotonsillitis), depending upon the clinical findings. In primary care settings, the Centor criteria are used to determine the likelihood of group A beta-hemolytic streptococcus (GABHS) infection in an acute tonsillitis and the need of antibiotics for tonsillitis treatment. However, the Centor criteria have their weaknesses in making precise diagnosis for adults. The Centor criteria are also ineffective in diagnosis for tonsillitis in children and in secondary care settings (hospitals). A modified version of the Centor criteria, which modified the original Centor criteria in