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Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction
Published on: February 24, 2014
Evaluation of poststreptococcal illness
Ricardo G Hahn1, Lynda M Knox, Todd A Forman
1Department of Family Medicine, University of Southern California, Los Angeles, California, USA. rghaha@usc.edu
Abstract:
Group A beta-hemolytic streptococcal pharyngitis, scarlet fever, and rarely asymptomatic carrier states are associated with a number of poststreptococcal suppurative and nonsuppurative complications. As in streptococcal pharyngitis, acute rheumatic fever, pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection, and poststreptococcal glomerulonephritis most often occur in children. The hallmarks of rheumatic fever include arthritis, carditis, cutaneous disease, chorea, and subsequent acquired valvular disease. Pediatric autoimmune neuropsychiatric disorders encompass a subgroup of illnesses involving the basal ganglia in children with obsessive-compulsive disorders, tic disorders, dystonia, chorea encephalitis, and dystonic choreoathetosis. Poststreptococcal glomerulonephritis is most frequently encountered in children between two and six years of age with a recent history of pharyngitis and a rash in the setting of poor personal hygiene during the winter months. The clinical examination of a patient with possible poststreptococcal complications should begin with an evaluation for signs of inflammation (i.e., complete blood count, erythrocyte sedimentation rate, C-reactive protein) and evidence of a preceding streptococcal infection. Antistreptolysin O titers should be obtained to confirm a recent invasive streptococcal infection. Other important antibody markers include antihyaluronidase, antideoxyribonuclease B, and antistreptokinase antibodies.
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Acute pharyngitis is the inflammation of the back of the throat (pharynx), commonly resulting in a sore throat. It is a frequently encountered condition that prompts individuals to seek medical advice.
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Acute pharyngitis can be categorized based on its underlying cause:
