Intrathecal immunoglobulin synthesis by diagnosis stage and reported duration of infection.

a: intrathecal synthesis where Q(Ig)>QLIM.
Significantly higher frequency in late stage cases compared to early stage cases * and *** p<0.05 and p<0.0001 respectively, fishers exact test.
Significant correlation of intrathecally synthesised Ig concentration with duration of illness. ¶, ¶¶ and ¶¶¶, p<0.05, p<0.01 and P<0.001 respectively, Spearman correlation test.