Therefore, throat culture is not routinely used in clinical practice for the detection of GABHS.Bacterial culture may need to be performed in cases of a negative rapid streptococcal test. An increase in antistreptolysin O (ASO) streptococcal antibody titer  following the acute infection can provide retrospective evidence of GABHS infection and is considered definitive proof of GABHS infection, but not necessarily of the tonsils. Epstein Barr virus serology can be tested for those who may have infectious mononucleosis with a typical lymphocyte count in full blood count result. Blood investigations are only required for those with hospital admission requiring intravenous antibiotics. Increased values of secreted phospholipase A2 and altered fatty acid metabolism  observed in people with tonsillitis may have diagnostic utility.Nasoendoscopy can be used for those with severe neck pain and inability to swallow any fluids to rule out masked epiglotitis and supraglotitis. Routine nasoendscopy is not recommended for children. Treatment
Treatments to reduce the discomfort from tonsillitis include:
pain and fever reducing medications such as paracetamol (acetaminophen) and ibuprofen
warm salt water gargle, lozenges, honey, or warm liquidsThere are no antiviral medical treatments for virally caused tonsillitis. Antibiotics
If the tonsillitis is caused by group A streptococcus, then antibiotics are useful, with penicillin or amoxicillin being primary choices. Cephalosporins and macrolides are considered good alternatives to penicillin in the acute care setting. A macrolide, such as azithromycin or erythromycin, is used for people allergic to penicillin. If penicillin therapy fails, bacterial tonsillitis may respond to treatment effective against beta-lactamase producing bacteria such as clindamycin or amoxicillin-clavulanate.
Red streaks in the skin along the direction of regional lymph nodes indicate lymphatic involvement. Infection may spread within hours and can cause sepsis and death. Symptoms and signs
Warm skin over site of infection. The person may also have chills and a high fever - between 38 and 40 degrees Celsius - along with moderate throbbing pain and swelling. The red streaks can be clearly outlined and demarcated or just barely visible, particularly in dark-skinned patients. Malaise, tenderness at the site of infection, skin ulcers (a rare symptom of lymphangitis), rapid pulse, and enlarged, swollen, and tender lymph nodes are also seen. Appetite loss has been documented with the presence of inflammation (inflammation-associated anorexia), but it is unclear whether appetite loss seen in patients with lymphangitis leads to weight loss; in cases that develop after lymphedema—which can be upwards of 8.14% of the time—weight gain has actually been documented.If these symptoms are absent, it is suggestive of other underlying disorders such as tuberculosis, lymphoma, or Hodgkin’s disease. A person with lymphangitis should be hospitalized and closely monitored by medical professionals. In very minor cases, regular application of antibiotic creams and cleanliness of the area can accelerate the healing process with no medical professional intervention or consultation required. When the inferior limbs are affected, the redness of the skin runs over the great saphenous vein location and can be confused for thrombophlebitis. Chronic lymphangitis is a cutaneous condition that is the result of recurrent bouts of acute bacterial lymphangitis.