Clinical Description of Patients with Systemic Lupus Erythematosus Evaluated in a Specialized Center for Rheumatic Diseases in Guatemala City

Introduction

SLE is a chronic inflammatory autoimmune disease characterized by the increase in autoantibodies which generates systemic inflammation and multi-organ involvement. Genetic, hormonal, environmental factors intervene in the etiopathogenesis, and it presents as a set of highly variable clinical manifestations, so its diagnosis is a challenge for the treating doctor. This disease has a worldwide dominance and occurs in all ethnic groups with a higher prevalence in African Americans. According to The Lupus Foundation of America, 1,5 million Americans and at least 5 million people worldwide have some form of lupus. (1,2)

The Spanish Registry of Patients with Systemic Lupus Erythematosus (RELES) is an observational, prospective, multicenter, cohort study that began in 2010 and is designed to study the prevalence of non-inflammatory complications in patients with SLE; 44 centers in Spain and institutions such as care centers for SLE patients in other countries, including Guatemala.

Objective

Create a prospective observational registry of SLE patients in the Guatemalan population, describing the classification criteria, disease activity index, organ damage index with special attention to non-inflammatory complications and treatment.

Material and methods

A total number of fifty-one SLE outpatients were included and followed-up for evaluation during the first quarter of 2020. The information was collected by direct clinical interview and analysis of the respective clinical records performed by the same researchers using a standard questionnaire for this purpose. The ACR 1997 classification criteria (3,4) was initially evaluated and in follow-up appointments, the indicators of disease activity SLEDAI-2K, organ damage index SLICC/ACR (5,6) were applied and the treatments were described.

We defined disease activity, using the score The Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2k), in: mild ≤6 points, moderate 7 - 12 points and high activity 12. The Organic damage index by SLICC/ACR includes the evaluation of >12 organ systems through 39 items that record the damage that has occurred in SLE patients. The data was collected through the RELES questionnaire and sent to the coordinating center of the S&H Medical Sciences Service based in Madrid where it was analyzed and was later forwarded and analyzed in statistical programs (SPSS), expressed in the descriptive analysis of frequency in 2 x 2 tables, as  appropriate for the calculation of ″p″ with statistical significance (<0.05).

The RELES group authorized that the data be used for the analysis and publication of our cohort. Data confidentiality was guaranteed and the ethical principles established by the Helsinki Declaration were respected.

Results

Of the 51 patients analyzed, 92.2% were female, with a 10:1 ratio.

Classification criteria

Applying the ACR 1997 classification criteria, the most frequent manifestation in SLE patients was arthritis 94.1%, ANA (+) 92.2%, anti-dsDNA 82.4%, anti-Sm 19.6% and proteinuria 37.3% (Table 1). When compared with the Spanish RELES study, we observed similar behavior in the frequency of these manifestations (9-15); 7.8% of patients were ANA (-) (1,7-9).

Disease activity

The precise measurement of SLE activity remains a challenge, due to the complexity of this disease, and the great variability of manifestations between patients has been recognized and even within the same patient over time (16). Applying the SLEDAI-2k score (7,17,18) we found patients with mild activity 58.8%, with moderate activity 25.5% and with high activity 15.6% at the time of the examination (Table 1). Most of the patients with high activity were new cases, late visits or absenteeism, probably conditioned by economic and cultural factors. Our study population is heterogeneous and we did not investigate genetic factors related to ethnic groups. We do not have local studies to compare our population and its disease activity index.

Organ damage

Using the SLICC/ACR index (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index for Systemic Lupus Erythematosus), the musculoskeletal system was the most affected (82.2%) with arthritis (72.5%), followed by neuropsychiatric conditions (17.7%) with peripheral neuropathies (13.7%) and the renal system (13.7%). The patients that presented an organ damage index ≤2 (70.6%), with an element of damage (43.1%) and no element of damage (15.7%) (Table 2). Comparative cohorts in South American countries like the evidenced studies of Medina and Londoño (21) informed a damage index of 51.1% with at least 1 element, the predominant clinical manifestation was musculoskeletal with arthritis, followed by cardiovascular affectations (myocardiopathy and history of heart attack); similar to our data (19-20,24).

Treatment

It is aimed at remission or low activity of the disease, prevention of accumulated damage, minimization of adverse effects of drugs and improvement of the quality of life of patients (10,20,23-24). In our cohort, the most widely used drugs were oral glucocorticoids (prednisone/deflazacort) (92.1%) and antimalarials (85.7%), followed by immunosuppressants: azathioprine (68.7%), mycophenolate mofetil (31.3%), methotrexate (23%) and oral cyclophosphamide (21.5%). The decreased use of hydroxychloroquine and mycophenolate mofetil is due to its cost. Of the patients treated with oral glucocorticoids, 64.6% received low doses (< 7.5 mg of prednisone or its equivalent), 21.8% moderate doses (7.5 to 30 mg) and 4% high doses (> 30 mg) (23,25).

Conclusions

Most of our patients with SLE are in low activity of the disease and are mostly maintaining low doses of corticosteroids, antimalarial drugs and one immunosuppressant. Arthritis is the most common clinical manifestation and ≤ 2 elements predominate on the organ damage scale. At AGAR, as a Guatemalan institution dedicated to the study and treatment of patients with rheumatic diseases, we are committed to achieving timely management, with the lowest rate of disease activity and the least organ damage in the medium and long term. Most of our population has low economic resources, little education and multiple comorbidities, which favors a high activity of the disease in some patients. However, most cases are diagnosed and treated early, which is reflected in a large proportion of patients with low activity and mild to moderate organ damage.