High prevalence of rheumatoid factor associated with clinical manifestations of rheumatic disease in Kaingang and Guarani Indians from Southern Brazil

Evaluation of rheumatoid factor and anti-citrullinated peptide antibodies in relation to rheumatological manifestations in patients with leprosy from Southern Brazil

BACKGROUND

Leprosy patients may present several osteoarticular complaints, which require further evaluation of inflammatory diseases, such as rheumatoid arthritis (RA). Therefore, an adequate clinical assessment in addition to testing for rheumatoid factors (RF) and anticyclic citrullinated peptide antibodies (anti-CCP), can be useful in order to establish the correct diagnosis.

METHOD

In this study, the relation of RF and anti-CCP with rheumatological manifestations was evaluated in 97 leprosy patients from Southern Brazil. The results were compared to RA patients and healthy controls from the same geographical area and ethnic background.

RESULTS

Neuropathy was observed in 71.1% and arthritis in 35.1% of the leprosy patients. A high frequency of RF positivity was observed among the leprosy patients (41.2%, 40/97), with RF immunoglobulin A (IgA) significantly associated with arthritis (OR = 7.9, 95% CI = 1.5-40.6 P = 0.008). Anti-CCP was observed in 9.3% (9/97) of the patients, with anti-CCP2 being the most frequent subtype. Only 4.1% (4/97) of the patients were RF and anti-CCP concomitantly positive. RF IgM showed a significant association with leprosy when compared to healthy controls (P < 0.0001) whereas for anti-CCP2 no significant results were observed (P = 0.0585). However, both biomarkers showed a strong association with RA when compared to leprosy in patients from the same geographical area and ethnic background (anti-CCP2 OR = 38.6; 95% CI = 16.49-90.26; P < 0.0001 and RF IgM OR = 4.51; 95% CI = 2.62-7.77; P < 0.0001).

CONCLUSION

Due to the similarity of some rheumatological manifestations in leprosy with other inflammatory diseases, such as RA, clinical and laboratorial evaluation of affected patients must be carefully assessed in order to achieve proper diagnosis and treatment.

Celiac disease in native Indians from Brazil: A clinical and epidemiological survey

Background:

Celiac disease has been described in populations from around the world, with recent data emphasizing the occurrence of the disease in ethnic minorities. There are only a few studies evaluating celiac disease in native Indians.

Aims:

This study aimed to screen the anti-endomysial antibody (IgA-EmA) in Kaingang and Guarani Indians from southern Brazil, in order to establish a clinical serological evaluation of celiac disease in these individuals.

Material and Methods:

Serum samples from 321 individuals (125 male and 196 female; 4-86 years old) from Mangueirinha Indigenous Reserve, State of Parana, Brazil, and 180 non-Indigenous healthy individuals (62 male and 118 female; 2-81 years old) were analysed to the presence of anti-endomysial antibody class IgA by indirect immunofluorescence assay. Amongst the Indians, 158 were Kaingang, 98 Guarani and 65 of mixed race. Indians presenting complaints of diarrhea (N=12) were also evaluated to the IgG class of anti-endomisyal antibody.

Results:

None of the individuals showed positive results either to IgA or IgG anti-endomysial antibodies.

Conclusions:

Although the results indicate an absence of celiac disease in Kaingang and Guarani Indians, the authors call attention to the importance of following up indigenous children or adults presenting gastrointestinal complaints or other symptoms related to the disease. Consideration should be given to the genetic background of these individuals, allied to the inter ethnic marriages and the changing habits or occupational activities, that have gradually introduced diseases previously not described in indigenous populations.