Clinical and laboratory features of patients with undifferentiated spondyloarthritis and ankylosing spondylitis

ABSTRACT Background: The terms Spondyloarthritis and spondyloarthropathy (Spa) are used to define a group of diseases with related clinical characteristics and genetics. Aim: To report the clinical and demographic characteristics of ankylosing spondylitis (AS) and undifferentiated spondyloarthritis (USpA) and to evaluate the frequency of cyclic citrullinated peptide antibody (anti-CCP) positivity. Material and Methods: Two hundred patients with USpA or AS, 100 control patients with a diagnosis of rheumatoid arthritis (RA) and 100 healthy volunteers were included. For each patient, their detailed medical histories, physical examination, whole blood counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), anti-CCP, routine biochemical tests, and HLA-B27 test results were evaluated. ASDAS and BASDAI scores and morning stiffness were used to evaluate the disease activity. Results: The presenting symptom of 73 (73%) patients in the AS group and 58 (58%) patients in the USpA group was pain in axial joints. A family history of Spa was positive in 32 patients from both groups (32%). A positive HLA-B27 was found in 55% of the AS group and 25% of the USpA group (p < 0.01 for the difference between groups). The frequency of positive HLA-B27 was significantly higher in individuals with a family history of SpA (p = 0.022). A positive Anti-CCP was found in 56% of the RA group, a significantly higher frequency compared with other groups (p < 0.001). The frequency of positive Anti-CCP in patients in AS (9%) and USpA (6%) was significantly higher than in healthy controls (p < 0.001). Conclusions: The frequency of anti-CCP positivity was higher in SpA patients than in healthy controls.

Introducción: Los términos espondiloartritis y espondiloatropatia (Spa) se usan para definir un grupo de enfermedades con características y genética relacionadas. Objetivo: Informar las características clínicas y demográficas de la espondilitis anquilosante (EA) y espondiloartritis indiferenciada (USpA) - y para evaluar la frecuencia de positividad del anticuerpo péptido citrulinado cíclico (anti-CCP). Material y Métodos: En este estudio observacional se incluyeron doscientos pacientes con USpA y EA, 100 pacientes control con diagnóstico de artritis reumatoide (AR) y 100 voluntarios sanos. Se evaluó la historia clínica, exámen físico, recuentos sanguíneos completos, velocidad de sedimentación globular (ESR), proteína C reactiva (PCR), anti-CCP, pruebas bioquímicas de rutina y resultados de la prueba HLA-B27. Para evaluar la actividad de la enfermedad se utilizaron las puntuaciones ASDAS y BASDAI y la rigidez matutina. Resultados: El síntoma inicial de 73 (73%) pacientes en el grupo de EA y 58 (58%) pacientes en el grupo de USpA fue dolor en las articulaciones axiales. Treinta y dos pacientes de cada grupo (32%) tenían antecedentes familiares de SPA. HLA-B27 fue positivo en el 55% del grupo AS y el 25% del grupo USpA con una diferencia significativa entre los dos grupos (p < 0.001). La frecuencia de positividad HLA-B27 fue mayor en individuos con historia familiar de SpA (p = 0,02). Se encontraron anti-CCP positivos en el 56% del grupo con AR, una frecuencia significativamente mayor en comparación con otros grupos (p < 0,01). La frecuencia de anti-CCP positivo fue mayor los pacientes con AS (9%) y USpA (6%) que en el grupo sano (p < 0,001). Conclusiones: La frecuencia de positividad anti-CCP fue mayor en los grupos de SpA en comparación con los grupos control sanos.

Clinical and laboratory features of patients with undifferentiated spondyloarthritis and ankylosing spondylitis.

BACKGROUND: The terms Spondyloarthritis and spondyloarthropathy (Spa) are used to define a group of diseases with related clinical characteristics and genetics. AIM: To report the clinical and demographic characteristics of ankylosing spondylitis (AS) and undifferentiated spondyloarthritis (USpA) and to evaluate the frequency of cyclic citrullinated peptide antibody (anti-CCP) positivity. MATERIAL AND METHODS: Two hundred patients with USpA or AS, 100 control patients with a diagnosis of rheumatoid arthritis (RA) and 100 healthy volunteers were included. For each patient, their detailed medical histories, physical examination, whole blood counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), anti-CCP, routine biochemical tests, and HLA-B27 test results were evaluated. ASDAS and BASDAI scores and morning stiffness were used to evaluate the disease activity. RESULTS: The presenting symptom of 73 (73%) patients in the AS group and 58 (58%) patients in the USpA group was pain in axial joints. A family history of Spa was positive in 32 patients from both groups (32%). A positive HLA-B27 was found in 55% of the AS group and 25% of the USpA group (p < 0.01 for the difference between groups). The frequency of positive HLA-B27 was significantly higher in individuals with a family history of SpA (p = 0.022). A positive Anti-CCP was found in 56% of the RA group, a significantly higher frequency compared with other groups (p < 0.001). The frequency of positive Anti-CCP in patients in AS (9%) and USpA (6%) was significantly higher than in healthy controls (p < 0.001). CONCLUSIONS: The frequency of anti-CCP positivity was higher in SpA patients than in healthy controls.