Liver cystic echinococcosis: which cysts are correlated with false negative indirect passive hemagglutination (IHA)?

It's generally agreed that calcified liver cystic Echinococcosis (CE) is associated with negative serology; the influence of other cystic features on serologic result remains unclear. The aim of this study is to determine predictive factors of negative indirect passive hemagglutination (IHA) in liver CE.

119 patients operated on for liver CE, had preoperative IHA. Correlation was studied between serological result and sex, age of patient and number (single vs multiple), size, ultrasonic type (unilocular, multivesicular, degenerative) and intrabiliary rupture of cyst.

IHA sensitivity was 74.8%. Univaried analysis showed that false negative serology was correlated with age <10 or >20 years (p < 0.01), single cyst (p < 0.006), cystic size <9 cm (p < 0.03) and unilocular or degenerative cyst in comparison with multivesicular type (p < 0.01 and p < 0.03 respectively).

in liver CE, cystic predictive factors of false negative IHA are single cyst, unilocular or degenerative type and size inferior to 9 cm.