Changing pattern of rheumatic fever in a paediatric ward : then and now

Objectives: To describe the socio-demographic and clinical features of children with primary episode of rheumatic fever (RF) during two periods of time and to attempt a comparison of the clinical features with previously published data from the same ward at Lady Ridgeway Hospital (LRH), Colombo. Method: Children admitted to University Paediatric Unit with the primary episode of RF based on the revised Jones criteria, were studied. Sociodemographic and clinical features were recorded prospectively from August 1994 to August 1999 and compared with data collected retrospectively from January 2004 to December 2008. Respecting the limitations, an attempt was made to compare this data with previously published data from the same ward during a period of ten years from 1966, when the primary episode of RF was diagnosed based on the modified Jones criteria. Results: There were 91 children from 1994 to 1999 and 52 (57%) were boys. Majority were >5 years and from families with a monthly income <Rs.10,000.00 but 56 (62%) of their mothers were educated up to Grade 10. Migratory polyarthritis was seen in 56 (62%) and 58 (64%) had a significant murmur on admission. Echocardiography was done on 87 and 24 (28%) had evidence of rheumatic heart disease (RHD). There were 29 (17 boys) during the 4 years from January 2004. Echocardiography was done on all the patients and 8 (28%) had RHD. During 1966 1976, RHD diagnosed on clinical features, was reported in 42% of 158 children (92 girls). Chorea has progressively increased through the years, with girls being more commonly affected. Conclusions: Childhood RF has declined in Sri Lanka. Disease pattern has also changed with more boys being affected but chorea continues to manifest more commonly in girls. RHD continues to be an important manifestation. ________________________________________ 1 Senior Lecturer in Paediatrics, Faculty of Medicine, University of Colombo (Revised version received on 23 April 2009. Accepted on 26 June 2009) Introduction Rheumatic fever (RF) has been an important cause of morbidity in Sri Lankan children. Stanley de Silva reported a series of 107 patients admitted to a ward at the Lady Ridgeway Hospital (LRH) during 1953 – 1957 1 and Priyani Soysa et al in their report 2 had 328 children admitted to the University Paediatric Unit in the same hospital over 10 years from 1966. In the recent past, the number of children admitted with rheumatic fever has declined.


Introduction
Rheumatic fever (RF) has been an important cause of morbidity in Sri Lankan children.Stanley de Silva reported a series of 107 patients admitted to a ward at the Lady Ridgeway Hospital (LRH) during 1953 -1957 1 and Priyani Soysa et al in their report 2 had 328 children admitted to the University Paediatric Unit in the same hospital over 10 years from 1966.In the recent past, the number of children admitted with rheumatic fever has declined.

Objectives
This study was done to describe the sociodemographic and clinical features of children with the primary episode of rheumatic fever (RF) admitted to a ward at LRH during two periods of time, and to attempt a comparison between the disease manifestations of the recent study with previously published data regarding the primary episode of RF, from the same ward.

Method
Children admitted to the University Paediatric Unit with RF conforming to the revised Jones criteria 3 from August 1994 to August 1999 were prospectively studied.The socio-demographic and clinical features were recorded and the children were examined by the investigator.Throat swabs were obtained on the day of admission and were cultured on blood agar.Beta haemolytic streptococci were isolated and subsequently identified as group A by using the Bacitracin test and Lancefield grouping 4,5,6 .Echocardiography was done at the Cardiology Unit of the National Hospital, Colombo as LRH did not have a cardiology unit at that time, and thus the investigation was done by different cardiologists over the years.
Hospital records of children admitted to the same ward with RF from January 2004 to December 2008, diagnosed according to the revised Jones criteria, were perused retrospectively and the data during these two periods of study were compared.A comparison was attempted with data published from the same ward from 1966 to 1976 subject to the limitations that the diagnosis of the primary episode of RF was based on the modified Jones criteria and RHD was a clinical diagnosis based on the presence of a cardiac murmur or evidence of cardiac failure or presence of pericarditis 2 .The modified (1956) and revised Jones criteria (1965/1984) are similar except that evidence of a recent streptococcal infection is an essential criterion in the latter definition whereas it was a minor criterion in the former 7 .The Ethical Review Committee of the Faculty of Medicine, Colombo approved the study.

Results
There were 96 children with various manifestations of RF admitted during the 5 years from 1994 to 1999.A significant seasonal variation in the admissions was not observed.Majority (91, 95%) were admitted with the primary episode, while 4 children had been previously diagnosed as having rheumatic heart disease (RHD) and one as having chorea.Twelve children gave a previous history of joint symptoms which had not been investigated.
Following is a description of the 91 children with the primary episode of RF.Fifty two (57%) were boys.Eighty four (92%) were more than 5 years of age.Seventy eight children (86%) came from families with a monthly income less than Rs.10,000.00 but 56 (62%) of their mothers were educated up to Grade 10 (Table 1).Fifty six (62%) presented with migratory polyarthritis while 58 (64%) had a significant murmur at presentation.Two children were in heart failure while 6 had clinical and echocardiographic evidence of infective endocarditis.Thirteen (08 girls) presented with chorea (Table 2).One child with RHD and infective endocarditis subsequently died after several admissions, 3 years after initial presentation.Investigations performed are given in Table 3.An ESR more than 50mm in the first hour was seen in 75 children (82%) while a significantly elevated ASOT ≥ 400 Todd units/ml was observed in 74 (81%).Throat swabs were obtained from 84 children and group A β haemolytic streptococci were isolated from 18 (21%) swabs.Echocardiography was performed during the hospital stay on 87 children.Twenty three of the 58 with a murmur had evidence of RHD and one child without a murmur had similar findings (Table 4).
Therefore in this series, 24 out of 87 (28%) with the primary episode of RF had echocardiographic evidence of RHD.

Discussion
RF is still rampant in developing countries, whereas the incidence is negligible in developed countries 7 apart from the resurgence reported from USA in 1987 8,9 .Improvement of housing and living standards is implicated as the reason for the very low incidence of RF in the more affluent countries of the world.According to the Demographic and Health Surveys 2000, 1993, 1987 of the Department of Census and Statistics, a survey of 8918 and 8169 houses in 1993 and 2000 respectively, has shown a possible improvement in our living standards.This is reflected by a reduction in the 'Mean household size' of 4.5 in 2000 from 4.7 in 1993.The 'Percent of one member households' has also increased to 3.7 in 2000 from 3.3 in 1993.