Email updates

Keep up to date with the latest news and content from BMC Public Health and BioMed Central.

Open Access Research article

Epidemiological characteristics of acute disseminated encephalomyelitis in Nanchang, China: a retrospective study

Chang-hui Xiong1, Yan Yan1*, Zhen Liao2, Shi-hui Peng2, Hai-rong Wen2, Yan-xia Zhang2, Shu-hua Chen3, Jian Li3, Hai-ying Chen2, Xiao-wu Feng2, Hui-qing Yao1, Li Huang1 and Li Zhang1

Author Affiliations

1 School of Public Health, Central South University, Changsha 410078, China

2 Nanchang City Center for Disease Control and Prevention, Nanchang, China

3 Donghu District Center for Disease Control and Prevention, Nanchang, China

For all author emails, please log on.

BMC Public Health 2014, 14:111  doi:10.1186/1471-2458-14-111

Published: 4 February 2014

Abstract

Background

Acute disseminated encephalomyelitis (ADEM) is an autoimmune disease that typically follows a monophasic course and may affect any age group. The precise population-based incidence of ADEM is still unknown in most countries. In China, there is no ADEM surveillance system. The exact incidence of ADEM is difficult to estimate, and other epidemiological characteristics of ADEM are unknown. The purpose of this study is to investigate the epidemiological characteristics of ADEM in Nanchang, China.

Methods

A retrospective investigation was conducted with ADEM patients admitted to second-level and third-level hospitals in Nanchang from 2008 to 2010, aiming to analyse the epidemiologic characteristics of ADEM in the population in Nanchang. ADEM patients, defined as patients who were diagnosed according to the consensus definition of ADEM provided by the International Pediatric MS Study Group, were enrolled in the study. The data were extracted from the ADEM patients’ medical records.

Results

Forty-seven ADEM patients were investigated. The average annual incidence was 0.31/100,000; the incidence among males (0.31/100,000) was nearly equal to that among females (0.31/100,000). The median age of onset was 25.97 years old, and the peak incidence was observed in the 5- to 9-year-old age group (0.75/100,000), followed by the over-60 age group (0.55/100,000). ADEM occurs throughout the year, but it occurs most frequently in March (n = 7) and least frequently in April and July (both n = 2). The patient numbers are roughly even in the other months. In the 2 months before the onset of ADEM, 15 patients presented with a preceding infection, but none of the patients received a vaccination. An increased number of vaccination was not accompanied by a corresponding increased number of cases of ADEM.

Conclusions

The average annual incidence of ADEM was 0.31/100,000 in Nanchang. The incidence among males was nearly equal to that among females. The peak age of onset was 5–9 years old. The peak season of onset was not apparent. There was no evidence of an association between increased number of vaccines administered and number of cases of ADEM in Nanchang, China.

Keywords:
Acute disseminated encephalomyelitis; Incidence; Epidemiology