Apparent Contrasting Rates of Pharyngitis and Pyoderma in Regions where Rheumatic Heart Disease is Highly Prevalent

Point of care testing for group A streptococci in patients presenting with pharyngitis will improve appropriate antibiotic prescription

“…Patients presenting to the Mount Isa Hospital ED with a sore throat showed a high prevalence of GAS infection (26%), resulting in a high positive predictive value of the POC test. While there have been high GAS prevalence found in the USA (20–30%) and Europe (30–40%), studies in the northern parts of the Northern Territory show a very low prevalence of GAS infection (0.1%) . This alerts to the fact that the prevalence documented in studies in other areas of Australia may not apply to northwest Queensland …”

“…The incidence of GAS colonisation of the pharynx of asymptomatic patients in literature is controversial and ranges from less than 2% to 11% per year . The positive rate of GAS swabs in the control group was low (<1%) much lower than found in the Northern Territory (3.7%) . Therefore, it is unlikely that they have confounded the results, implying that the test has some value for ruling in patients with positive GAS swab for antibiotic treatment in a setting similar to Mount Isa with high prevalence of GAS pharyngitis and low prevalence of asymptomatic carriers.…”

Extensive Diversity of Streptococcus pyogenes in a Remote Human Population Reflects Global-Scale Transmission Rather than Localised Diversification

“…In the Indigenous population of this zone, S. pyogenes pharyngitis appears rare [10]. Despite this, this population has one of the highest burdens of ARF and RHD in the world [2], which challenges the dogma that S. pyogenes skin infections do not play a role in these pathologies [10], [11]. Paradoxically, in the southern region of the NT, which is arid with low humidity, pyoderma rates appear lower than in the northern region, pharyngitis is more common, but the incidence of acute rheumatic fever and the prevalence of rheumatic heart disease are similar to the tropical north [11].…”

“…Despite this, this population has one of the highest burdens of ARF and RHD in the world [2], which challenges the dogma that S. pyogenes skin infections do not play a role in these pathologies [10], [11]. Paradoxically, in the southern region of the NT, which is arid with low humidity, pyoderma rates appear lower than in the northern region, pharyngitis is more common, but the incidence of acute rheumatic fever and the prevalence of rheumatic heart disease are similar to the tropical north [11]. Post-streptococcal glomerulonephritis is also frequently seen in the NT, with epidemics seen in the northern region and sporadic cases in the south [12], [13].…”

Etiologic predictive value of a rapid immunoassay for the detection of group A Streptococcus antigen from throat swabs in patients presenting with a sore throat

“…Furthermore, the proportion of patients having GAS may vary in different settings from close to zero up to 40%. 2,3 In unselected cases in primary health care or similar settings it would most often be between 5% and 25%. Clinical decision rules have not shown appropriate predictive values to be considered sufficient for clinical decision-making alone as to whether or not to treat a sore throat as a GAS infection.…”