Detection of Anti-Echinococcus granulosus Antibodies in Humans: An Update from Pakistan

Human cystic echinococcosis (CE) is a zoonotic disease caused by the larval stage of Echinococcus granulosus sensu lato that causes economic losses by affecting livestock and also poses a public health threat worldwide. The present study is the first retrospective report on the seroprevalence of anti-E. granulosus antibodies in humans in Pakistan. The study used data from 93 blood analysis reports of patients suspected of having CE from different medical centers in Lahore, Pakistan. Out of 93 sera samples, 20 (21.5%) were seropositive, and higher seropositivity (17.2%) was recorded with the indirect hemagglutination test (IHA) than with enzyme-linked immunosorbent assay (ELISA). The findings indicated that age, gender, and year had no significant relationship with the seropositivity of CE. The current study provides directions towards the management of the disease in the near future in Pakistan.

Isolated Renal Hydatid Cyst in a 6-Year-Old Boy: A Case Report

Hydatid cyst (HC) is a parasitic infection transmitted by oral ingestion of Echinococcus granulosus eggs. Isolated kidney involvement is extremely rare. It is even less common in children. We present a case of isolated renal HC in a 6-year-old boy from Şanlıurfa, southeast Turkey who complained of abdominal pain and distension. Cystectomy was performed with a flank incision using the extraperitoneal approach. No recurrence was detected in the postoperative 6-month follow-up. There are not enough data about the efficacy of medical treatment in renal HC. Therefore, medical treatment should be considered pre- and post-operatively to prevent dissemination, rather than being used as a primary treatment. Kidney-sparing surgery should be the first choice in patients with isolated renal HC. However, nephrectomy is recommended for nonfunctioning kidneys, large cysts thought to be connected with the collecting system, and cysts with suspicious tumor. In societies where HC disease is endemic, renal HC should be considered in children with cysts located in kidney, even if the indirect hemagglutination test is negative.

Melioidosis: Laboratory Investigations and Association with Patient Outcomes

Melioidosis is an infection caused by the bacterium Burkholderia pseudomallei. The most common presentation is bacteremia occurring in 38–73% of all patients, and the mortality rate ranges from 9% to 42%. Although there is abundant data representing risk factors for infection and patient outcomes, there is limited information regarding laboratory investigations associated with bacteremia and mortality. We assessed a range of baseline and diagnostic investigations and their association with patient outcomes in a retrospective cohort study in Townsville, Australia. About 124 patients’ medical and laboratory records were reviewed between January 1, 1997 and December 31, 2020. Twenty-seven patients died and 87 patients were bacteremic. The presence of lymphopenia (< 1.5 × 109 cells/L) was the highest risk for bacteremia (relative risk [RR] 2.2; 95% CI: 1.3–3.7, P < 0.001). Factors associated with mortality included lymphopenia, (RR: 1.4; 95% CI: 1.2–1.6, P = 0.004); uremia (RR: 1.7; 95% CI: 1.1–2.5, P = 0.03); and an elevated international normalized ratio (RR: 1.5; 95% CI: 1.2–2.0, P = 0.006). Median incubation to positive blood culture result was 28 hours with 15/82 (18%) positive in ≤ 24 hours. For serological testing during admission only 53/121 (44%) were indirect hemagglutination assay positive, 67/120 (56%) enzyme immunoassay IgG positive, and 23/89 (26%) IgM positive. Simple baseline investigations at time of presentation may be used to stratify patients at high risk for both bacteremia and mortality. This information can be used as a decision aid for early intensive management.

Presence of atypical genotypes of Toxoplasma gondii isolated from cats in the state of Bahia, Northeast of Brazil

In this study, 20 blood, heart, and brain samples were collected from euthanized cats at the Zoonosis Control Centers and Veterinary Clinics in the state of Bahia, Brazil. The sera were examined for anti-T. gondii antibodies using the indirect hemagglutination test. The brains and hearts of seven seropositive cats were ground, and peptide digestion was performed for bioassay in mice. Toxoplasma gondii was isolated in 5/7 (71.42%) of seropositive cats. In these isolates, the parasite was genotyped using the Polymerase chain reaction, associated with the DNA fragment polymorphism obtained by restriction enzyme PCR-RFLP technique with 11 markers (SAG1, 5’-SAG2, 3’-SAG2, alt. SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3) and 15 microsatellite markers (TUB-2, W35, TgM-A, B18, B17, M33, IV.1, XI.1, M48, M102, N60, N82, AA, N61, N83). The analysis of the isolates by PCR-RFLP revealed five distinct genotypes. Three of these genotypes have never been reported before; one corresponded to the TgDgCo13 genotype, and one incomplete genotype. In genotyping analysis using microsatellite markers, it was observed that the isolates showed atypical alleles in the typing and fingerprint markers. This revealed five atypical genotypes. The typing marker B17 showed the highest degree of atypia. This study is the first to report the genotyping of T. gondii obtained from naturally infected cats in Bahia, Northeast Brazil. The genotypes found in this study were different from those found in other studies conducted in Bahia, which included different species of animals. None of the clonal lineages I, II, or III were found. This study demonstrates the diversity of T. gondii in the study region, with the presence of unusual genotypes, reaffirming the genetic variability of the parasite in Brazil.

A case of pseudotuberculosis with lethal outcome

A rare case of pseudotuberculosis with lethal outcome in the child aged two months and 20 days is described. Y. pseudotuberculosis infection of the child occurred likely in using milk, for the second time contaminated by the pseudotuberculosis pathogene. The inhibition reaction of indirect hemagglutination is more sensitive method of revealing Y. pseudotuberculosis than the bacteriologic method.

Indirect hemagglutination reaction in the differential diagnosis of bovine tuberculosis

The main problem of improving the health of farms from tuberculosis is diagnosis, in particular, differential diagnosis. Despite the comprehensive study and a fairly impressive number of proposed diagnostic methods, including on the molecular genetic level, the problem of differentiation of non-specific reactions remains topical today. About effectiveness of serological methods of research, in particular, indirect hemagglutination reactions, in the literature there are scattered and polar data. In the methods of setting up reactions, in the variety of antigens, methods of adsorption of agglutinins, stabilization of red blood cells, etc., the researchers ' opinions differ. Four methods of stabilization of sheep erythrocytes sensitized with polysaccharide antigen (Feeli, Weinbach, Ling, RES) have been comparatively studied. The maximum antibody titer was established for the stabilization of red blood cells by Feeli. A total of 1911 blood samples from four farms with different relationships to tuberculosis were studied in the reaction of indirect hemagglutination with diagnostics from Mycobacterium bovis and Mycobacterium fortuitum. Relatively high positive indicators of the reaction of indirect hemagglutination were revealed in animals in farms with tuberculosis problems, in which the diagnosis was confirmed by pathoanatomic method in 87.5% of cases. The results of the tuberculin test coincided with the results of indirect hemagglutination reactions in 37.07% of cases. Diagnostic antibody titers were detected in 201 anergic animals of the treated herd and in 5 from the isolation unit. During the slaughter of 20 heads from a dysfunctional farm and 5 from the overexposure group, tuberculosis was established in 15 and 5, respectively. The practical significance of the reaction of indirect hemagglutination with different diagnostics in the detection of homologously infected animals is shown.

Metapneumovirus infection of poultry: development of sovereign method of diagnosis and epizootological monitoring in poultry farms of Ukraine

The main biological (cultural) properties of field isolates of metapneumovirus (MPV) were studied, normal and hyperimmune sera to metapneumovirus for IHR-diagnosticum (erythrocyte diagnosticum based on indirect hemagglutination reaction) were obtained, and a set of M-component components was developed. A diagnostic system of IHR (indirect hemagglutination reaction) was developed, with the help of which epizootological monitoring was carried out in poultry farms and the spread of a new infectious disease of poultry (metapneumovirus infection) among turkeys and chickens in poultry farms of Ukraine was studied. The purpose of the research is to develop a domestic diagnostic test system (erythrocyte diagnosticum for IHR) for metapneumovirus infection (MPVI) or infectious avian rhinotracheitis (IRT). As a result of the conducted researches metapneumovirus infection or infectious rhinotracheitis was established in poultry farms of 4 regions of Ukraine. The pathogen was isolated, its molecular-biological properties were studied by PCR (polymerase chain reaction), and it was established that it belongs to the genus Metapneumovirus (MPV), subtype B. The results of the epidemiological monitoring indicate that the developed erythrocyte MPV (IRT) antigen based on IHR is sensitive and specific and can be used to control the spread of metapneumovirus infection and the intensity of immunity in birds vaccinated against this disease. The production inspection in poultry farms in the western regions of Ukraine established the possibility of using IHR-diagnosticum for control of MPVI. As a result of the performed work the new domestic method of diagnostics, forecasting and protection of poultry against a metapneumovirus infection is offered. Prospects for further research are to use this erythrocyte diagnosticum based on the indirect hemagglutination reaction to monitor metapneumovirus infection of birds in poultry farms in Ukraine and determine the epizootic situation for this disease.

Comparison of Dot ELISA Using GroEL Recombinant Protein as an Antigen and an Indirect Hemagglutination Assay for Serodiagnosis of Melioidosis

Background: Melioidosis is a disease caused by the Burkholderia pseudomallei bacterium. The mortality rate of infected patients is quite high because the symptoms are similar to those of various diseases, making it difficult to diagnose clinically and preventing the immediate treatment with effective antibiotics that is required for the management of acute infections. To provide appropriate treatment, accurate and rapid diagnosis is required. Objective: The aims of this study were to develop Dot ELISA using purified GroEL B. pseudomallei recombinant protein as an antigen and to compare the newly developed assay with an indirect hemagglutination assay (IHA) for the diagnosis of melioidosis. Methods: The GroEL recombinant protein was purified by immobilized metal affinity chromatography before being used as an antigen. The optimal conditions of the Dot ELISA were determined and used for subsequent experiments. A total of 291 serum samples were evaluated by the established Dot ELISA and IHA, using the bacterial culture method as the gold standard of melioidosis diagnosis. Results: The results from Dot ELISA and IHA revealed sensitivity, specificity, and accuracy of 85.7% (Dot ELISA)/64.3% (IHA), 94.4%/85.5%, and 93.1%/82.5%, respectively. Conclusion: These results indicate that the Dot ELISA developed is an efficient, simple, rapid and cost-effective technique for the early diagnosis of melioidosis and can be used in a local laboratory without specialized equipment.

Development of new antigens for serologic diagnosis of animal trypanosomosis and their use for epizootic monitoring

The purpose of the research is developing a method for obtaining erythrocyte antigens containing and not containing Trypanosoma equiperdum and T. evansi DNA, which can later be used in serological reactions to differentiate these types of Trypanosoma.Materials and methods. The studies were conducted in the Protozoology Laboratory and the Vyshnevolotsk Branch of the Federal State Budget Scientific Institution “Federal Scientific Centre VIEV RAS”, as well as livestock farms of the Russian Federation and other countries using clinical, microscopic, hematological, parasitological, biomolecular and serological methods.Results and discussion. Studies carried out for the first time have shown that it is possible to use erythrocyte antigens containing the T. equiperdum and T. evansi DNA obtained after 3-fold administration to mice and rabbits of a mixture of trypanosomal antigen with addition of 1.0 ml of an adjuvant (aluminum hydroxide), and bleeding of animals at 25 to 30 days. The formed precipitate was used as an antigen for serological tests. Experiments have shown that blood for preparation of positive serum can be taken when antibodies are in titers of 1:20 in the Prolonged Complement Fixation Test, and at least 1:400 in the Indirect Hemagglutination Test and ELISA, and for negative serum when horse blood serum reacts negatively with antigens of T. equiperdum and T. evansi in the Prolonged Complement Fixation Test, Indirect Hemagglutination Test and ELISA. The test systems of the Prolonged Complement Fixation Test, Indirect Hemagglutination Test and ELISA prepared by us with antigens containing and not containing T. equiperdum and T. evansi DNA resulted in creating a universal test system (Indirect Hemagglutination Test) for differentiating T. equiperdum from T. evansi.