Spondyloarthritis in Kinshasa, DR Congo: Epidemiology, phenotype, immunogenetic, clinical diagnosis and management.

Chronic arthritides are hardly studied in central Africa. Our recent studies in Rheumatoid arthritis in the DR Congo showed different demographic and phenotypic characheristics compared to a Caucasian population. Data in the field of Spondyloarthritis (SpA) are scarses. The current project aims to study the epidemiology, clinical diagnosis including immunogenetic phenotype and management of SpA in Kinshasa, DR Congo. It will be based on four studies: 1. Study 1: Development and validation of a screening questionnaire for SpA 1.1. Objectives: - to develop and validate a screening questionnaire to identify patients with a high likelihood of having SpA for use in clinical setting and epidemiological studies - to evaluate the frequency of SpA in rheumatologic practice in Kinshasa 1.2. Methods: This study will be conducted with rheumatologic patients attending at University Hospital of Kinshasa (UHK) and the Provincial General Hospital of Kinshasa (PGHK) in the period from November 2018 to February 2019. We will develop an item questionnaire assessing symptoms and signs seen among patients with SpA as determined by an experience rheumatologist. Additional validation of this questionnaire will be done in a second group of SpA and other inflammatory and non-inflammatory rheumatisms. Study 2: Epidemiology of spondyloarthritis in Kinshasa 2.1. Objectives - to determine the prevalence of SpA - to determine its distribution among linguistic groups in the urban area of Kinshasa - to identify determinants of the prevalence in Kinshasa 2.2. Methods This study will be conducted in the ppulation of Kinshasa. The prevalence of Sp will be determined on a random sample of at least 8,000 inhabitants of Kinshasa based on an unbiased selection strategy and taking account the know ethnic heterogeneity. This study will be conducted in the period from April 2019 to August 2019. After screening with the ad hoc questionnaire above, all suspected cases will be invited to the University Hospital of Kinshasa for case confirmation. For this purpose, the suspects will undergo a physical examination and x-rays; inflammatory biomarkers (ESR, CRP) will be determined and HLA-B27. The history of recent infection will be checked. The family history and previous or current treatments, ethnicity, occupation and social status of patients will be noted. Patients will be classified according to existing criteria as ASAS, ESSG and Amor. HLA-B27 positivity will be assessed in patients confirmed with SpA. The prevalence of HLA-B27 in the Congolese population will be estimed from samples of volunteer blood donors. HLA typing will be performed in the Laboratory of Tissue Homeostasis and Disease, Skeletal Biology and Engineering Center (Prof Dr Rik Lories) of the KU Leuven in Belgium. Study 3. Genotype and phenotype of Spondyloarthritis in Kinshasa 3.1. Objectives: - to describe the phenotype features and the immunogenetic profile of SpA in Kinshasa - to assess the radiological severity - to assess the association between the presence of HLA-B27 and phenotype severity 3.2. Methods This study will be conducted in the Rheumatology unit of the UHK and the PGHK in the period from November 2019 to January 2020. Patients with SpA presenting spontaneously will be evaluated for articular and extra-articular SpA features by interview, clinical evaluation and imaging. The BASDAI, BASFI and BASMI will be calculated. The complementary tests will include blood count, inflammatory biomarkers (ESR, CRP), stool tests (direct and after concentration examinations, culture) and urine (urinary sediment and culture), HIV serology and HLA-B27. HLA typing will be performed in the laboratory of Tissue Homeostasis and Disease, Skeletal Biology and Engineering Center (Prof Dr Rik Lories) of the KU Leuven in Belgium. Patients will be classified according to existing criteria as ASAS, ESSG and Amor. Study 4. Clinical assessment and management of Spondyloarthritis in Kinshasa 4.1. Objectives: - to describe the clinical features of SpA in Kinshasa - to assess evolution of SpA with NSAID treatment and exercice till 6 months later - to determine the clinical remission and its determinants 4.2. Methods This study will be conducted in the Rheumatology unit of the UHK and the PGHK in the period from June 2020 to November 2020. Patients with SpA presenting spontaneously will be included consecutively. Patient enrolled in the study 2 (see above) will also be included. Patients will be evaluated forarticular and extra articular SpA features by clinical evaluation and imaging. The BASDAI, BASFI, BASMI and ASDAS will be calculated. Patients will receive a treatment with NSAID and exercice. The follow up at 6th month will determine the rate of improvement and explore the modalities and difficulties of thie treatment and the specific perception of patient will be explored additionally.