Jack S

Moreland NJ

Meagher J

Fittock M

Galloway Y

Ralph AP

2018-09-25

Globally, there is wide variation in streptococcal titer upper limits of normal (ULN) for antistreptolysin O (ASO) and anti-deoxyribonuclease B (ADB) used as evidence of recent group A streptococcal (GAS) infection to diagnose acute rheumatic fever (ARF). We audited ASO and ADB titers among individuals with ARF in New Zealand (NZ), and in Australia's Northern Territory (NT). We summarized streptococcal titers by different ARF clinical manifestations, assessed application of locally-recommended serology guidelines where NZ uses high ULN cut-offs, and calculated the proportion of cases fulfilling alternative serologic diagnostic criteria. From January 2013-December 2015, GAS serology results were available for 350 patients diagnosed with ARF in NZ, and 182 patients in NT. Median peak streptococcal titers were similar in both settings. Among NZ cases, 267/350 (76.3%) met NZ serologic diagnostic criteria while 329/350 (94.0%) met Australian criteria. By applying Australian ULN titer cut-off criteria to NZ cases, excluding chorea, ARF definite cases would increase by 17.6% representing 47 cases. ASO and ADB values were similar in these settings. Use of high ULN cut-offs potentially undercounts definite and probable ARF diagnoses. We recommend NZ and other high-burden settings use globally accepted age-specific lower serologic cut-offs to avoid misclassification of ARF.

Centre for International Health, Department of Preventive and Social Medicine, University of Otago, Dunedin, New Zealand.. Institute of Environmental Science and Research, Wellington, New Zealand..

School of Medical Sciences and Maurice Wilkins Centre, University of Auckland, New Zealand..

Royal Darwin Hospital, Darwin, Northern Territory, Australia..

Northern Territory Rheumatic Heart Disease Control Program, Darwin, Northern Territory, Australia..

Institute of Environmental Science and Research, Wellington, New Zealand..

Royal Darwin Hospital, Darwin, Northern Territory, Australia.. Global and Tropical Health, Menzies School of Health Research, Darwin, Northern Territory, Australia..

The Pediatric infectious disease journal 2018-09-25

https://pubmed.ncbi.nlm.nih.gov/30256313/?otool=iaurydwlib

https://hdl.handle.net/10137/7078

Streptococcal Serology in Acute Rheumatic Fever Patients: Findings from Two High-income, High Burden Settings.

Journal Article

Publication