Date Published: January 17, 2019
Publisher: Public Library of Science
Author(s): Nafiu Amidu, Benedict Boateng Antuamwine, Otchere Addai-Mensah, Abass Abdul-Karim, Azure Stebleson, Braimah Baba Abubakari, John Abenyeri, Afia Serwaa Opoku, John Eyulaku Nkukah, Ali Sidi Najibullah, Adriana Calderaro.
Bacterial meningitis is a public health crisis in the northern part of Ghana, where it contributes to very high mortality and morbidity rates. Early detection of the causative organism will lead to better management and effective treatment. Our aim was to evaluate the diagnostic accuracy of Pastorex and Wellcogen latex agglutination tests for the detection of bacterial meningitis in a resource-limited setting. CSF samples from 330 suspected meningitis patients within the northern zone of Ghana were analysed for bacterial agents at the zonal Public Health Reference Laboratory in Tamale using polymerase chain reaction (PCR) and two latex agglutination test kits; Pastorex and Wellcogen. The overall positivity rate of samples tested for bacterial meningitis was 46.4%. Streptococcus pneumoniae was the most common cause of bacterial meningitis within the sub-region, with positivity rate of 25.2%, 28.2% and 28.8% when diagnosed using Wellcogen, Pastorex and PCR respectively. The Pastorex method was 97.4% sensitive while the Wellcogen technique was 87.6% sensitive. Both techniques however produced the same specificity of 99.4%. Our study revealed that the Pastorex method has a better diagnostic value for bacterial meningitis than the Wellcogen method and should be the method of choice in the absence of PCR.
Bacterial meningitis is a huge public health problem especially in the northern parts of Ghana, making its contribution to mortality and morbidity rates difficult to overlook. Whilst the global outlook on meningitis indicates a mortality rate of 2–30%, that of Ghana is estimated to be between 36–50%, with majority of the cases occurring within the northern zone [1–3]. The location of northern Ghana within the imaginary boundaries of the meningitis belt of sub-Saharan Africa accounts for the high burden of the infection in the region [4, 5].
Bacterial meningitis is a life threatening contagious disease, endemic in most developing countries, and thus requires early diagnosis [6, 31]. Worldwide, about 500,000 cases of meningococcal disease occur annually with 10% mortality rate . The severity of these infections and the outbreaks they cause have necessitated the development and use of several rapid test kits for the diagnosis of bacterial meningitis. Concerns have however been raised about the diagnostic accuracy of these rapid test kits [21, 22].
Our study has shown that the Pastorex method has a better diagnostic value for bacterial meningitis than the Wellcogen method. A diagnostic sensitivity of 97.4% and a specificity of 99.4% in the detection of bacterial meningitis by the Pastorex technique are remarkable. The study also found a high positivity rate of bacterial meningitis within the northern zone of Ghana to be 46.4%, with S. pneumoniae being the most common causative organism in the sub-region.