Items in AFP with MESH term: Streptococcus pyogenes
Pharyngitis - Article
ABSTRACT: Sore throat is one of the most common reasons for visits to family physicians. While most patients with sore throat have an infectious cause (pharyngitis), fewer than 20 percent have a clear indication for antibiotic therapy (i.e., group A beta-hemolytic streptococcal infection). Useful, well-validated clinical decision rules are available to help family physicians care for patients who present with pharyngitis. Because of recent improvements in rapid streptococcal antigen tests, throat culture can be reserved for patients whose symptoms do not improve over time or who do not respond to antibiotics.
Evaluation of Poststreptococcal Illness - Article
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.
ABSTRACT: Erythema nodosum, a painful disorder of the subcutaneous fat, is the most common type of panniculitis. Generally, it is idiopathic, although the most common identifiable cause is streptococcal pharyngitis. Erythema nodosum may be the first sign of a systemic disease such as tuberculosis, bacterial or deep fungal infection, sarcoidosis, inflammatory bowel disease, or cancer. Certain drugs, including oral contraceptives and some antibiotics, also may be etiologic. The hallmark of erythema nodosum is tender, erythematous, subcutaneous nodules that typically are located symmetrically on the anterior surface of the lower extremities. Erythema nodosum does not ulcerate and usually resolves without atrophy or scarring. Most direct and indirect evidence supports the involvement of a type IV delayed hypersensitivity response to numerous antigens. A deep incisional or excisional biopsy specimen should be obtained for adequate visualization. Erythema nodosum represents an inflammatory process involving the septa between subcutaneous fat lobules, with an absence of vasculitis and the presence of radial granulomas. Diagnostic evaluation after comprehensive history and physical examination includes complete blood count with differential; erythrocyte sedimentation rate, C-reactive protein level, or both; testing for streptococcal infection (i.e., throat culture, rapid antigen test, antistreptoly-sin-O titer, and polymerase chain reaction assay); and biopsy. Patients should be stratified by risk for tuberculosis. Further evaluation (e.g., purified protein derivative test, chest radiography, stool cultures) varies based on the individual. Erythema nodosum tends to be self-limited. Any underlying disorders should be treated and supportive care provided. Pain can be managed with nonsteroidal anti-inflammatory drugs.
ABSTRACT: Common signs and symptoms of streptococcal pharyngitis include sore throat, temperature greater than 100.4 degrees F (38 degrees C), tonsillar exudates, and cervical adenopathy. Cough, coryza, and diarrhea are more common with viral pharyngitis. Available diagnostic tests include throat culture and rapid antigen detection testing. Throat culture is considered the diagnostic standard, although the sensitivity and specificity of rapid antigen detection testing have improved significantly. The modified Centor score can be used to help physicians decide which patients need no testing, throat culture/rapid antigen detection testing, or empiric antibiotic therapy. Penicillin (10 days of oral therapy or one injection of intramuscular benzathine penicillin) is the treatment of choice because of cost, narrow spectrum of activity, and effectiveness. Amoxicillin is equally effective and more palatable. Erythromycin and first-generation cephalosporins are options in patients with penicillin allergy. Increased group A beta-hemolytic streptococcus (GABHS) treatment failure with penicillin has been reported. Although current guidelines recommend first-generation cephalosporins for persons with penicillin allergy, some advocate the use of cephalosporins in all nonallergic patients because of better GABHS eradication and effectiveness against chronic GABHS carriage. Chronic GABHS colonization is common despite appropriate use of antibiotic therapy. Chronic carriers are at low risk of transmitting disease or developing invasive GABHS infections, and there is generally no need to treat carriers. Whether tonsillectomy or adenoidectomy decreases the incidence of GABHS pharyngitis is poorly understood. At this time, the benefits are too small to outweigh the associated costs and surgical risks.
Making Decisions at the Point of Care: Sore Throat - Improving Patient Care
Defending the Real Standard of Care - The Last Word
ABSTRACT: Bacteria are responsible for approximately 5 to 10 percent of pharyngitis cases, with group A beta-hemolytic streptococci being the most common bacterial etiology. A positive rapid antigen detection test may be considered definitive evidence for treatment; a negative test should be followed by a confirmatory throat culture when streptococcal pharyngitis is strongly suspected. Treatment goals include prevention of suppurative and nonsuppurative complications, abatement of clinical signs and symptoms, reduction of bacterial transmission and minimization of antimicrobial adverse effects. Antibiotic selection requires consideration of patients' allergies, bacteriologic and clinical efficacy, frequency of administration, duration of therapy, potential side effects, compliance and cost. Oral penicillin remains the drug of choice in most clinical situations, although the more expensive cephalosporins and, perhaps, amoxicillin-clavulanate potassium provide superior bacteriologic and clinical cure rates. Alternative treatments must be used in patients with penicillin allergy, compliance issues or penicillin treatment failure. Patients who do not respond to initial treatment should be given an antimicrobial that is not inactivated by penicillinase-producing organisms (e.g., amoxicillin-clavulanate potassium, a cephalosporin or a macrolide). Patient education may help to reduce recurrence.
Group A Beta-Hemolytic Strepococcal Pharyngitis - Editorials
Diagnosis and Management of Group A Streptococcal Pharyngitis - Practice Guidelines
Strep Throat - Point-of-Care Guides