Rheumatoid factor in non-rheumatoid black patients

Area of Science:

• Rheumatology
• Immunology
• Clinical Medicine

Background:

• Rheumatoid factor (RF) is an autoantibody often associated with rheumatic diseases.
• Understanding RF prevalence and causes in non-rheumatic populations is crucial for accurate diagnosis.
• Previous research has not fully elucidated RF prevalence in Black patients without rheumatic conditions.

Purpose of the Study:

• To estimate the prevalence of positive rheumatoid factor (RF) in Black patients without rheumatic diseases.
• To identify potential causes and associated conditions of RF positivity in this cohort.
• To investigate the relationship between gamma-globulin levels and RF positivity.

Main Methods:

• A cohort of 301 Black patients without diagnosed rheumatic diseases was studied.
• The latex slide test was employed to detect rheumatoid factor.
• Gamma-globulin levels, including IgG, were analyzed in relation to RF status.

Main Results:

• A significant prevalence of 25% for positive rheumatoid factor was observed.
• 21% of patients exhibited a 'diagnostic' titre of 80 or higher.
• A significant association was found between elevated gamma-globulin levels (especially IgG) and RF positivity.

Conclusions:

• Rheumatoid factor positivity is prevalent in Black patients without rheumatic diseases.
• Elevated gamma-globulin levels, particularly IgG, are significantly related to RF positivity.
• Cirrhosis and tuberculosis were the most common comorbidities among sero-positive patients.