Prevalence of autoimmune manifestations in patients with large granular lymphocytic leukemia: Exploratory analysis of a series of consecutive patients.

Abstract

6555 Background: Review of literature suggests certain autoimmune abnormalities to accompany LGL leukemia. The present study was set to identify the prevalence of autoimmune phenomena in LGL leukemia patients and compare it with same in general population. Methods: We conducted both retrospective and prospective analyses in a series of consecutive patients (n=11) with LGL leukemia that had been followed in outpatient setting. Median age was 71 years ( ± 14 years). The presence of associated autoimmune disorders in our cohort was compared to the published prevalence of these conditions in general population. Statistical analysis: The obtained values were tested for statistical significance using Fisher’s exact test for small number of observations (95% confidence); a p value < 0.05 was considered significant. Results: A total of 45% patients in our study were diagnosed with autoimmune conditions. Identified autoimmune disorders included rheumatoid arthritis [RA] (n=3), Hashimoto thyroiditis (n=3), Felty syndrome (n=1), aplastic anemia (n=1), pernicious anemia (n=1), and leukocytoclastic vasculitis (n=1). Statistical analysis showed the following significance: Hashimoto thyroiditis (p=0.044), RA (p=0.003), Felty syndrome (p<0.001), aplastic anemia (p<0.001), pernicious anemia (p<0.001), and leukocytoclastic vasculitis (p<0.001). Statistical difference was also noted for autoimmune serologic abnormalities, with ANA positivity present in 63.6% of the cases (p< 0.001) and RF present in 50% of the patients (p=0.005). Conclusions: Nearly half of LGL leukemia patients in our cohort had autoimmune conditions, thus significantly exceeding the overall prevalence in general population. Statistically significant differences were recorded for RA, Hashimoto thyroiditis, Felty syndrome, aplastic anemia, pernicious anemia, leukocytoclastic vasculitis, ANA and RF positive serologies. The prevalence of Hashimoto thyroiditis and ANA positivity in our patient cohort was significantly higher than the one in existing literature. Given the relatively small size of the analyzed cohort, larger studies are expected to confirm our findings.