Antistreptolysin O titer in health and disease: levels and significance.

Alyaa Amal Kotby,Nevin Mamdouh Habeeb,Sahar Ezz El Elarab

doi:10.4081/pr.2012.e8

Alyaa Amal Kotby, Nevin Mamdouh Habeeb + Show 1 more

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https://doi.org/10.4081/pr.2012.e8

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Journal: Pediatric reports	Publication Date: Feb 9, 2012
Citations: 26	License type: CC BY 4.0

Affiliation: Ain Shams University Hospital

Abstract

Over diagnosis of acute rheumatic fever (ARF) based on a raised antistreptolysin O titer (ASOT) is not uncommon in endemic areas. In this study, 660 children (aged 9.2 ±1.7 years) were recruited consecutively and classified as: G1 (control group, n=200 healthy children), G2 (n=20 with ARF 1st attack), G3 (n=40 with recurrent ARF), G4 (n=100 with rheumatic heart disease (RHD) on long acting penicillin (LAP)), G5 (n=100 with acute follicular tonsillitis), and G6 (n=200 healthy children with history of repeated follicular tonsillitis more than three times a year). Serum ASOT was measured by latex agglutination. Upper limit of normal (ULN) ASOT (80th percentile) was 400 IU in G1, 200 IU in G4, and 1600 IU in G6. Significantly high levels were seen in ARF 1st attack when compared to groups 1 and 5 (P<0.001 and P<0.05, respectively). ASOT was significantly high in children over ten years of age, during winter and in those with acute rheumatic carditis. ASOT showed significant direct correlation with the number of attacks of tonsillitis (P<0.05). Egyptian children have high ULN ASOT reaching 400 IU. This has to be taken into consideration when interpreting its values in suspected ARF. A rise in ASOT is less prominent in recurrent ARF compared to 1st attack, and acute and recurrent tonsillitis. Basal levels of ASOT increase with age but the pattern of increase during infection is not age dependent.

Highlights

Introduction recurrentacute rheumatic fever (ARF), diagnosed according to updated kit
Acute rheumatic fever (ARF) is rel- prophylaxis; taining elevated levels of ASO antibodies on a atively rare in developed economies, it is much Group 4: 100 patients with slide, clear agglutination is seen within 2 min
More common in the developing world and chronic RHD, all of whom had mitral regurge This test has been calibrated to WHO ASO First among aboriginal populations.[1]

Summary

Materials and Methods

This is a cross-sectional case control study conducted on 660 patients chosen consecutively from the Children’s Hospital and Pediatric Cardiology clinic, Ain Shams University Hospital, a tertiary referral center in Cairo. Group 1: 200 apparently healthy children with no history of recent tonsillitis or sore doi:10.4081/pr.2012.e8 patients with acute follicular tonsillitis. Group 3 (recurrent RF): 40 patients with tion of ASOT in serum using Avitex ASO test. Acute rheumatic fever (ARF) is rel- prophylaxis; taining elevated levels of ASO antibodies on a atively rare in developed economies, it is much Group 4 (chronic RHD): 100 patients with slide, clear agglutination is seen within 2 min. The ULN in our studied control group was even centile).[12] ASOT values were positively skewed and so the raw data were log-transformed prior to using the statistical test, and the results were presented as geometric means and 95%. ANOVA (analysis of variance) was used to test the difference about mean values of ASOT among the six groups, in ly different seasons and in different presentations of patients with acute rheumatic fever. ARF, acute rheumatic fever; RHD, rheumatic heart disease; H of recurrent F tonsillitis, history of recurrent follicular tonsilli [page 26]

Acute follicular tonsillitis

Findings

Practice guidelines for the diagnosis and