Conversión de prueba cutánea de derivado proteico purificado durante el tratamiento con anti-TNF / Skin test conversion of purified protein derivative during treatment with anti-TNF

Introducción: los anti-TNF-α se asocian con mayor riesgo de desarrollar tuberculosis (TB). La prueba del derivado proteico purificado (purified protein derivative, PPD) se emplea para diagnosticar infección de tuberculosis latente (ITL). Se recomienda el cribado para TB previo al inicio de terapia anti-TNF-α y el seguimiento para evaluar la posible conversión de la PPD durante el tratamiento. El tratamiento de la ITL puede reducir el riesgo de desarrollar enfermedad activa en un 90%. Objetivos: actualmente los resultados de conversión de la PPD y su interpretación durante el tratamiento anti-TNF-α son variables, por tal motivo nos propusimos conocer la frecuencia de conversión de la PPD en este grupo de pacientes de nuestro medio. Materiales y métodos: realizamos un estudio descriptivo, observacional y retrospectivo que incluyó pacientes >18 años, diagnosticados con enfermedad reumática, tratados con anti-TNF-α. Resultados: se incluyeron 54 pacientes (46,7 ± a 12 años), de los cuales 36, presentaron diagnóstico de artritis reumatoidea, seis de artritis idiopática juvenil, cinco de espondilitis anquilosante, tres de artritis psoriásica, tres de uveítis y uno de queratitis intersticial. Los tratamientos fueron: 30 adalimumab, 17 certolizumab, siete etanercept, 44 metotrexato, 19 leflunomida, nueve hidroxicloroquina, dos sulfasalazina, dos azatioprina, uno mofetil micofenolato y glucocorticoides (28 de 54); la conversión de la PPD ocurrió en un solo paciente. Conclusiones: en el presente trabajo la seroconversión fue baja en contraste con otras series. La prueba de PPD es un método accesible, ampliamente disponible, adecuado y sensible para diagnosticar ITL.

Introduction: anti-TNF-α are associated with an increased risk of developing tuberculosis (TB). Purified protein derivative (PPD) is used to demonstrate a latent TB infection (LTBI). Screening is recommended for TB prior to the onset of anti-TNF-α and monitoring evaluating possible conversion of PPD during treatment. Treatment of LTBI can reduce the risk of active disease development by up to 90%. Objectives: currently the results of PPD conversion and its interpretation during anti-TNF-α treatment are variable and that is why we set out to know the frequency of conversion of PPD in this group of patients in our environment. Materials and methods: a descriptive, analytical, observational, retrospective study was conducted. Including patients >18 years old, diagnosed with rheumatic disease, treated with anti-TNF-α. Results: 54 patients were included (46.7 ± to 12 years), of which 36 presented a diagnosis of rheumatoid arthritis, 6 juvenile idiopathic arthritis, 5 ankylosing spondylitis, 3 psoriatic arthritis, 3 uveitis, 1 interstitial keratitis. The treatments were: 30 adalimumab, 17 certolizumab, 7 etanercept, 44 methotrexate, 19 leflunomide, 9 hydroxychloroquine, 2 sulfasalazine, 2 azathioprine, 1 mycophenolate mofetil and glucocorticoids (28/54). PPD conversion took place in 1 patient. Conclusions: in the present study, seroconversion was low in contrast to other series. The PPD test is an accessible, widely available, adequate and sensitive method for diagnosing LTBI, which the rheumatologist should use in his daily practice.

Chagas disease reactivation in rheumatologic patients: association with immunosuppressive therapy and humoral response.

Evidence for Chagas disease reactivation (CDR) in rheumatologic patients under rheumatologic treatments (RTs) is scarce. To screen and follow-up patients with rheumatic diseases and concomitant Chagas disease under RT to detect CDR and to describe a possible relationship between CDR and specific RT. An observational, longitudinal, prospective, consecutive study was carried out between 2018 and 2020. Included patients were evaluated during the follow-up for clinical and laboratorial manifestations of CDR. Direct blood parasitological examination (Strout method) and polymerase chain reaction (PCR) were employed to diagnose CDR. The dynamic of anti-T. cruzi-specific antibodies was also assessed by IHA and ELISA (total IgG and Anti-SAPA). Fifty-one patients were included (86% women). Rheumatoid arthritis was the predominant disease (57%). Classic DMARDs (86.3%) and corticosteroids (61%) were the most frequent RT. CDR was developed in 6 patients (11.7%), exhibiting both positive Strout and PCR. Symptomatic reactivation of CD (fever, asthenia, arthralgias, myalgias) occurred in two patients who had previously been diagnosed with it. Regardless of the different RT, all patients who experienced CDR had previously received more than ≥ 20 mg/day of prednisone equivalent. Despite immunosuppression, patients with CDR exhibited increased levels of specific anti-T. cruzi and anti-SAPA antibodies, which decreased after anti-parasitic treatment. CDR is possible in rheumatologic patients, especially after receiving high doses of corticosteroids. Since CDR symptoms may mimic rheumatic disease activity, monitoring of Chagas disease is highly recommended before, during and after immunosuppression. Key Points • Chagas disease reactivation (CDR) in the context of rheumatological treatment was associated to high doses of corticosteroids. • CDR was associated with an increase in anti-T. cruzi antibodies despite the immunosuppressive treatment. • Suspecting and anticipating CDR is mandatory in this patient population to diagnose and treat it.