A correlative study of ultrasound with serology in an area in China co‐endemic for human alveolar and cystic echinococcosis

Abstract

SummaryWe correlated ultrasound (US) imaging classifications for human alveolar echinococcosis (AE) and cystic echinococcosis (CE) with serology (ELISA and immunoblotting (IB) incorporating native and recombinant/purified echinococcal antigens) in community surveys (2001)(2002)(2003) and follow-up (2002 and 2003) of US-confirmed cases in Ningxia, China. One hundred and seventy-one cases (96 with AE, 75 with CE) were identified; of these, US classification and serological data were obtained for 142 and 112 cases, respectively. Seropositive-rates increased in CE patients with highly viable unilocular cyst lesions (Types CL, CE 1 or CE 2) to degenerating primary lesions (CE 3), but then decreased in subjects with inactive (CE 4) or dead (CE 5) cysts. In contrast, there was a constant increase in seropositivity from the early (P1, P2) to the advanced stages (P3, P4) with AE cases. For US-confirmed cases, follow-up by US combined with serology is invaluable for studying the clinical progression of echinococcosis and for detecting recurrent cysts or reinfection post-treatment.

Factors Influencing the Serological Response in Hepatic Echinococcus granulosus Infection

“…The stage of the cyst is the variable most often investigated in correlation with serology results, with a consensus finding that patients with CE1 and CE4-CE5 (hepatic) cysts are seronegative in a high percentage of cases (30-58% and 50-87%, respectively), while rates of negativity are lower in the presence of CE2 and CE3 cysts (5-20%). 10,[12][13][14] When the variables associated with serology results were investigated in more detail, serodiagnosis performance correlated with stage, number (single versus multiple), location (liver versus lungs), and size (< or > than 15 cm) of cysts; presence of complications; and collection of serum after treatment. 10,11,13,15 Although in the majority of cases of hepatic CE the combined use of imaging and serology allows for a reliable diagnosis, in some instances they are inconclusive, and differential diagnosis with other lesions may be challenging.…”

Echinococcosis

“…Up to 20 % of patients with single hepatic and up to 50 % of those with lung CE cysts may be seronegative, while patients with cysts in other localizations are often seronegative Barbieri et al 1998). In the case of hepatic cysts, patients with CE1 and CE4-CE5 cysts are often seronegative (30-58 % and 50-87 % respectively), while rates of negativity are lower in the presence of CE2 and CE3 cysts (5-20 %) (Hernandez-Gonzalez et al 2012;Li et al 2010Li et al , 2011bYang et al 2007;Ortona et al 2000). Presence of multiple cysts, complications, and therapy are associated with positive serological results (HernandezGonzalez et al 2012;Li et al 2011b;Ben Nouir et al 2008;Santivanez et al 2012).…”

Cystic and Alveolar Echinococcosis: Fraternal Twins both in Search of Optimal Treatment

“…(Yang et al 2007(Yang et al , 2008aZhang et al 2012;Feng et al 2010;Liance et al 2000;Ito and Craig 2003). From the available literature and clinical experience, it may be stated that: (1) complement fixation tests are no longer used because of their poor sensitivity and specificity; (2) indirect haemagglutination and latex tests, using crude Echinococcus extracts, are both relatively inexpensive and sensitive, but poorly specific; (3) immunoelectrophoresis or immunosyneresis are specific, but poorly sensitive and time-consuming; they are no longer used; , commercialized by Bordier Affinity Products, Crissier, Switzerland, or the rapid DOT-immunogold assay, commercialized by Xinjiang Key Lab, Urumqi, P.R.…”

“…However, diagnostic efficiency of serology is limited both by 1) the reduced capacity of some infected patients to develop specific antibodies (or some isotypes), for genetic or acquired reasons (such as immunosuppression) and 2) the absence of release of specific antigens by the cysts in CE, which decreases sensitivity, and by the existence of infected-non-diseased persons in endemic areas, which decreases specificity. Positive serological results in individuals at mass screening account for at least five different situations: (1) "patent", overt disease with symptoms, (2) "latent", non-apparent disease; (3) calcified dead lesions in the liver; (4) CE cyst in the lung or other organs and rare cases of isolated extra-hepatic AE despite no US lesions in the liver; and, (5) no parasitic lesions at all (Yang et al 2007(Yang et al , 2008a. Negative serology with patent CE or AE lesions have been found in all mass screening surveys and is the rule in all published hospital case series (Yang et al 2007(Yang et al , 2008b.…”

“…Positive serological results in individuals at mass screening account for at least five different situations: (1) "patent", overt disease with symptoms, (2) "latent", non-apparent disease; (3) calcified dead lesions in the liver; (4) CE cyst in the lung or other organs and rare cases of isolated extra-hepatic AE despite no US lesions in the liver; and, (5) no parasitic lesions at all (Yang et al 2007(Yang et al , 2008a. Negative serology with patent CE or AE lesions have been found in all mass screening surveys and is the rule in all published hospital case series (Yang et al 2007(Yang et al , 2008b. Serology should thus never been used as a "first intent" test, but always combined with ultrasound imaging in mass screening, and only be used as a confirmation test for a suspected diagnosis based on imaging techniques in clinical settings.…”