immune deviation in recurrent vulvovaginal candidiasis: correlation with iron deficiency anemia

background: iron deficiency anemia (ida) has been controversially linked to il-4 production in previous studies. a predominant th1 response leads to resistance against recurrent vulvovaginal candidiasis (rvvc), whereas a th2 response exacerbates the disease. objective: to investigate the possible effect of iron deficiency on the host’s susceptibility to rvvc as a result of the th1/th2 cytokine polarization. methods: we conducted a case-control study of 92 women in 4 groups based on strict inclusion and exclusion criteria: rvvc+ida+ group consisted of 23 women with rvvc and ida; rvvc+ ida- group consisted of 23 women with rvvc without ida; rvvc-ida+ group consisted of 23 women without rvvc and with ida and rvvc- ida- group consisted of 23 healthy women. the iron parameters and key cytokines (ifn-γ, il-10, il-12, il-4) were measured in blood samples. results: comparison of il-4 production between rvvc+ ida+ (12.2 ± 1.3 pg/ml) and rvvc+ ida- (2.4 ± 4.0 pg/ml) groups (p=0.044), between rvvc- ida+ (14.6 ± 1.7 pg/ml) and rvvc- ida- (1.28 ± 3.6 pg/ml) groups (p=0.006), between rvvc- ida+ (14.6 ± 1.7 pg/ml) and rvvc+ ida-) 2.4 ± 4.0 pg/ml) groups (p=0.009) and also between rvvc+ ida+ and rvvc- ida- (1.28 ± 3.6 pg/ml) groups (p=0.03) showed significant differences. we found a significant positive correlation between il-4 and total iron binding capacity (tibc, p=0.046) and between serum il-10 and hb levels (p=0.041) in the rvvc+ ida- group. there was also a significant negative correlation between serum il-4 and levels of serum iron (si, p=0.041) in the rvvc- ida- group. conclusion: it seems that ida determines the balance between and the intensity of th1 and th2 arms of the immune response and leads to a deviation toward th2 response which could contribute to recurrence of candidiasis.