A Comparative Study of Different Immunoassays to Detect Specific Antibodies to Echinococcus Spp. in Human Sera

Performance of Echinococcosis Serology is Associated with Disease Endemicity, Hydatid Cyst Location, Eosinophilia, Imaging Finding, and Treatment

BACKGROUND

We aimed to assess echinococcosis serology performance for diagnosing cystic echinococcosis (CE) in children living in CE-endemic vs. non-endemic populations, and in different clinical settings.

METHODS

A retrospective cohort study, assessing children with ELISA test for echinococcosis, 2005-2021. Sensitivity, specificity, positive and negative predictive values (PPV and NPV) were calculated comparing CE-endemic vs. non-endemic populations, cases with/without eosinophilia, and cases with/without CE-suggestive imaging findings. Additionally, we examined the association between serology titers/levels (values) and clinical characteristics.

RESULTS

Of 273 cases, 66 (24%) were confirmed as CE. Overall, 97% of CE were in Bedouin children, and the pre-test probability was 28% vs. 9% (p < 0.001) in CE-endemic vs. non-endemic population, respectively. Sensitivity was higher in hepatic than extra-hepatic CE (74% vs. 47%). Overall specificity was 86%. PPVs were higher in CE-endemic population compared to non-endemic (66% vs. 22%), while NPVs were higher in non-endemic population (100% vs. 87%). Eosinophilia was associated with lower specificity (73% vs. 94%) and PPV (47% vs. 78%). Typical imaging was associated with higher specificity (94% vs. 82%) and PPV (91% vs. 11%), while NPVs were lower in typical imaging cases (77% vs. 98%). Higher titer levels (above median) were associated with typical imaging (76% vs. 49%), higher PPV (79% vs. 43%), albendazole treatment (100% vs. 56%), surgery (60% vs. 19%), and new imaging finding (75% vs. 0%).

CONCLUSIONS

Echinococcosis serology performance was impacted by disease endemicity, and by various clinical characteristics. These findings may assist physicians in the interpretation of echinococcosis serology results.

Parasitic and Vector-Borne Infections in HIV-Positive Patients in Slovakia-Evidence of an Unexpectedly High Occurrence of Anaplasma phagocytophilum

In HIV (human immunodeficiency virus) infected people, the immunodeficiency caused by a reduced level of CD4 (cluster of differentiation 4) T-lymphocytes increases the risk of infectious diseases. Additionally, in individuals with immunologically compromising conditions, tick-borne or some parasitic pathogens may cause chronic, debilitating opportunistic infections and even death. The study aimed at determining the IgG seropositivity of HIV-infected patients to Toxoplasma gondii, Toxocara spp., Echinococcus multilocularis, and E. granulosus s.l. and performing the molecular identification of T. gondii and some tick-borne pathogens, namely, Borrelia spp., Babesia spp., Anaplasma phagocytophilum, Rickettsia spp., and Bartonella spp. Out of 89 HIV-positive patients, specific IgG antibodies to T. gondii were detected in 17 (19.1%) and to Borrelia spp. in 12 (13.5%) individuals. Seropositivity to Toxocara spp., E. multilocularis, and E. granulosus s.l. was not recorded. Molecular approaches showed positivity to T. gondii in two (2.2%) patients, and 11 (12.4%) individuals had positive PCR signal for the msp2 gene of A. phagocytophilum. Relatively high prevalence of A. phagocytophilum in HIV-positive patients suggests that these people are more susceptible to some vector-borne pathogens. The presence of opportunistic infections may pose a health risk for patients with weakened immune systems, and should not be neglected during the regular monitoring of the patient’s health status.

Alveolar Echinococcosis of the Liver with a Rare Infiltration of the Adrenal Gland

Human alveolar echinococcosis (AE) is a silently-progressing disorder that has become a threat in many countries. Since 2000, when the first case was recorded, the number of human AE patients in Slovakia is on continuous raise. The article presents a rare case of alveolar echinococcosis with infiltration in the adrenal gland and discusses the problems associated with differential diagnosis of the disease. In 2016, abdominal ultrasound performed due abdominal pain complaint showed the presence of cystic lesions in the right liver lobe of 54-year old female patient. During surgery, another lesion in the right adrenal gland was found, and neoplastic processes or echinococcosis were considered in the differential diagnosis. Due to unclear correlation between radiology, serology and histopathology results and endemic situation in Slovakia, molecular examination was recommended. Subsequently E. multilocularis was confirmed as etiological agent of infection. Alveolar echinococcosis is considered as a rare disease, with very few patients referred to clinicians or hospitals that sometimes have almost none existing experience with the diagnosis and treatment of the disease. Therefore, the establishment of networks or reference centres specialized on management of the disease would be suitable way to provide the patients with the best care and improve the disease diagnosis, treatment and prognosis.