Diagnosis Of Mixed Infection Research Articles

Infecção mista de Bartonella e Eperythrozoon em um cão - relato de caso

ABSTRACT A March male Golden, weighing 7.6kg, presented with gradual weight loss, high body temperature, depression, poor appetite and thirst, and vomiting before consultation. The results showed that the erythrocytes, hematocrit, hemoglobin, and platelets were lower than the reference values. The diagnosis of mixed infection with haematocrit and eosinophilic bodies was confirmed by real-time fluorescence PCR of whole blood, which was positive for haematocrit and eosinophilic bodies. The dog was treated with doxycycline and ceftriaxone, and the dog fully recovered after 2 weeks with blood transfusion, symptomatic treatment, and supportive therapy. This indicates that the disease can be treated well by a comprehensive treatment approach.

Nanopore Technology Applied to Targeted Detection of Tomato Brown Rugose Fruit Virus Allows Sequencing of Related Viruses and the Diagnosis of Mixed Infections

Tomato (Solanum lycopersicum) plants from a commercial glasshouse were identified with symptoms compatible with a tomato brown rugose fruit virus (ToBRFV) infection. Reverse transcription-PCR and quantitative PCR confirmed the presence of ToBRFV. Subsequently, the same RNA sample and a second from tomato plants infected with a similar tobamovirus, tomato mottle mosaic virus (ToMMV), were extracted and processed for high-throughput sequencing with the Oxford Nanopore Technology (ONT). For the targeted detection of ToBRFV, the two libraries were synthesized by using six ToBRFV sequence-specific primers in the reverse transcription step. This innovative target enrichment technology enabled deep coverage sequencing of ToBRFV, with 30% of the total reads mapping to the target virus genome and 57% mapping to the host genome. The same set of primers applied to the ToMMV library generated 5% of the total reads mapping to the latter virus, indicating that sequencing of similar, non-target viral sequences was also allowed. Further, the complete genome of pepino mosaic virus (PepMV) was also sequenced from the ToBRFV library, thus suggesting that, even using multiple sequence-specific primers, a low rate of off-target sequencing can usefully provide additional information on unexpected viral species coinfecting the same samples in an individual assay. These results demonstrate that targeted nanopore sequencing can specifically identify viral agents and has sufficient sensitivity towards non-target organisms to provide evidence of mixed virus infections.

Application of Alveolar Lavage Fluid Second-Generation Sequencing in the Treatment of Severe Pneumonia

To observe the application of alveolar lavage fluid second-generation sequencing in diagnosing and guiding the treatment of patients with severe pneumonia with unidentified pathogenic bacteria and to provide novel ideas and methods for the effective clinical treatment of this disease. The clinical data of 80 patients with severe pneumonia included in our intensive care unit from June 2020 to June 2022 were analyzed and all patients had undergone metagenomic next-generation sequencing and traditional cultures (alveolar lavage fluid culture, sputum culture) to analyze the advantages of metagenomic next-generation sequencing in detecting pathogens in patients with severe pneumonia. The positive rate of metagenomic next-generation sequencing pathogen detection was higher than that of conventional culture. In patients who were negative for conventional culture and positive for metagenomic next-generation sequencing, metagenomic nextgeneration sequencing was able to further identify multiple pathogenic infections. In terms of pathogen distribution, metagenomic next-generation sequencing detected 71 bacterial, 39 fungal and 3 viral strains. In mixed infections, metagenomic next-generation sequencing yielded a higher rate of positive diagnosis. In addition, metagenomic next-generation sequencing had a higher pathogen detection rate in patients with combined underlying diseases and metagenomic next-generation sequencing could identify specific pathogenic infections especially in patients with combined immunocompromised conditions. Metagenomic next-generation sequencing could improve the detection rate of pathogenic microorganisms in patients with severe pneumonia and could be used as a complementary test for patients negative for conventional cultures. Metagenomic next-generation sequencing has advantages in the diagnosis of mixed infections and can identify multiple pathogenic infections simultaneously. Clinically, early application of metagenomic next-generation sequencing in patients with severe pneumonia is recommended for increased clinical benefit.

Clinical case of associative course of panleukopenia and intestinal yersiniosis in cats

The study of the course and manifestation of mixed infections is an important modern problem of both humane and veterinary medicine because their diagnosis is quite complex and time-consuming. The clinical manifestation of double and sometimes triple infection has its characteristics, which depend on various biotic and abiotic factors. To date, it has been proven that the associative course of several infectious diseases is registered more and more often, which confirms the case of simultaneous manifestation of panleukopenia and intestinal yersiniosis in domestic outbred cats. Diagnosis of mixed infection was comprehensive through general clinical and laboratory studies, the use of rapid test systems to confirm the diagnosis of panleukopenia and RNGA with specific yersinia antigens to determine the status of intestinal yersiniosis in cats. The latter was caused by serovar Y. enterocolitica O: 9 with a diagnostic titer of 1: 400. Thanks to microbiological studies, the causative agent of intestinal yersiniosis Y. enterocolitica was isolated. Its biological properties were determined, and antimicrobial sensitivity to enrofloxacin and doxycycline was established against the background of polyresistance to ceftriaxone and tetracycline. During treatment, it was found that the clinical case of intestinal yersiniosis was also due to the simultaneous infection of Y. enterocolitica with two types of serotypes O: 3 and O: 9. Which also have their own specific features. But in most cases, we have different sensitivity to antibacterial drugs, in contrast to the case we described. Clinical signs of the associated course of panleukopenia and intestinal yersiniosis in domestic outbred cats were characterized by prolonged diarrhea, streaks of blood and mucus, apathy, refusal to feed, general weakness. Therapeutic measures containing antibacterial drugs, energy sources, crystalloids, buffer infusions which were aimed at reducing dehydration and maintaining water-salt balance in the complex, were effective, clinical signs of the disease disappeared on the eighth day of treatment, and complete isolation of the pathogen in the environment ceased on the thirteenth day, which indicated the complete recovery of the animal. However, to prevent re-infection, it was recommended to treat disinfectants with care items and utensils. And also to avoid direct contact with animals that have pronounced clinical signs of disease. To prevent the occurrence of panleukopenia, scheduled mass vaccinations with mandatory observance of time limits.

Diagnosis of mixed infections with swine viruses using an integrated microfluidic platform

Early diagnosis and intervention of livestock epidemics is extremely important because disastrous outbreaks of an infectious disease can not only hit livestock industry but also cause a series of negative economic and social consequences. In order to fulfill the requirement of point-of-care testing, a reliable, field-portable, time-efficient and cost-effective microfluidic platform including a microfluidic chip and a semi-automated immunoassay system (SAIS) is developed. Multiple samples can be tested simultaneously in a single chip for multiple-biomarker testing. The entire assay, including reagent injection, well washing, waste collection and colorimetric detection, can be realized in the user-friendly system. The assay of three contagious diseases, PRRSV, CSFV and PCV2, is conducted in the microfluidic platform. The consistency of the reaction for different samples can be guaranteed owing to the chip design for flow balance. The assay only takes 12 min and 4 μL of sample is required. The assay achieves high accuracy (>93.8 %), high sensitivity (>88.8 %) and high specificity (>96.6 %). The platform has the potential to be applied for on-site rapid screening livestock diseases.

Severe heartworm disease in two dogs cured by an alternative therapy

The objective of this paper is to describe two cases of heartworm disease in dogs presented with ascites and dyspnea. A diagnosis of mixed infection with both Dirofilaria immitis (D. immitis) and Dirofilaria repens (D. repens) was established in the first case, while D. immitis was detected in the other dog. Based on clinical, parasitological, laboratory and radiographic examinations, the diagnosis of severe stage heartworm disease (HWD) was established because both dogs were in heart failure due to HWD. An alternative therapeutic protocol with combined doxycycline and ivermectin was used as an antiparasitic treatment in both cases. No microfilariae were detected after 30 and 60 days, and no antigen to D. immitis was detected after 8 and 12 months in the first and second case, respectively. Based on the clinical examinations and parasitological testing performed, the two dogs were considered cured of HWD by this alternative therapy.

Immunohistochemical localization of viral antigens causing immunosuppressive diseases in poultry under field conditions

The present study was conducted to diagnose viral diseases viz. Chicken Infectious Anaemia(CIA), Infectious Bursal Disease (IBD) and Avian Reovirus (ARV)infection causing immunosuppression in commercial poultry flocks. Tissue samples were collected from affected birds showing lesions in lymphoid organs. The formalin-fixed, paraffin embedded lymphoid tissues were processed for assessing histopathological changes and localization of viral antigens associated with immunosuppression in chickens under field conditions. The histopathological scores in lymphoid organs were correlated with localization of viral antigens in lymphoid organs using Pearson correlation coefficient. The results indicated high prevalence (23%) of mixedinfection of CIA, IBD and ARV. Among various viral diseases, highest incidence of CIA (18%) was found to be statistical significant (÷2 =9.23; P<0.05). A significant positive correlation was observed between histopathological score and immonohistochemical localization of viral antigens in thymus (0.60; P<0.05), spleen (0.63; P<0.05), bursa (0.51; P<0.05) and caecal tonsils (0.80; P<0.05). In conclusion, Chicken Anaemia Virus (CAV) causes mixed infection with other immunosuppressive viruses under field conditionsand imunohistochemical localization of these viral antigens in the formalin-fixed, paraffin-embedded tissue sections can be used effectively for differential diagnosis of mixed infection.

Development and application of an in-house reverse hybridization method for Chlamydia trachomatis genotyping

To develop and evaluate an in-house reverse hybridization technique for Chlamydia trachomatis genotype identification. The evaluation of the developed and optimized reverse hybridization method on reference strains showed the specific detection of all genotypes. This technique showed its ability to type one inclusion-forming unit of C.trachomatis genotype E and equivalent sensitivity to the Cobas TaqMan assay. It was also able to detect mixed infections in vitro. Application of the reverse hybridization method on 38 isolated C.trachomatis strains and their respective swabs allowed the detection of six urogenital genotypes D, E, F, G, H and K and one trachoma genotype B. Genotype E was the most prevalent, detected in 73% of the swab samples. Mixed infections were detected in 26% of swab cases. The reverse hybridization technique is simple and does not require specialized instruments. It is powerful in the diagnosis of mixed infections and is suitable for use in epidemiological studies. This technique allowed rapid C.trachomatis genotype identification.

Amplification of a Specific Repetitive DNA Sequence for Trypanosoma rangeli Identification and Its Potential Application in Epidemiological Investigations

Vargas, N., Souto, R. P., Carranza, J. C., Vallejo, G. A., and Zingales, B. 2000. Amplification of a specific repetitive DNA sequence for Trypanosoma rangeli identification and its potential application in epidemiological investigations. Experimental Parasitology 96, 147– 159. Trypanosoma rangeli can infect humans as well as the same domestic and wild animals and triatomine vectors infected by Trypano soma cruzi in Central and South America. This overlapping distribution complicates the epidemiology of American trypanosomiasis due to the cross-reactivity between T. rangeli and T. cruzi antigens and the pres ence of conserved DNA sequences in these parasites. We have isolated a T. rangeli-specific DNA repetitive element which is represented in approximately 103 copies per parasite genome and is distributed in several chromosomal bands. The 542-bp nucleotide sequence of this element, named P542, was determined and a PCR assay was standard ized for its amplification. The sensitivity of the assay is high, allowing the detection of one tenth of the DNA content of a single parasite. The presence of the P542 element was confirmed in 11 T. rangeli isolates from mammalian hosts and insect vectors originating from several countries in Latin America. Negative amplification was ob served with different T. cruzi strains and other trypanosomatids. The potential field application of the P542 PCR assay was investigated in simulated samples containing T. rangeli and/or T. cruzi and intestinal tract and feces of Rhodnius prolixus. Epidemiological studies were conducted in DNA preparations obtained from the digestive tracts of 12 Rhodnius colombiensis insects collected in a sylvatic area in Colombia. Positive amplification of the P542 element was obtained in 9/12 insects. We have also compared in the same samples the diagnostic performance of two PCR assays for the amplification of the variable domain of minicircle kinetoplast DNA (kDNA) and of the large subunit (LSU) of the ribosomal RNA gene of T. cruzi and T. rangeli. Data indicate that the kDNA PCR assay does not allow diagnosis of mixed infections in most insects. On the other hand, the PCR assay of the LSU RNA gene showed lower sensitivity in the detection of T. rangeli than the PCR assay of the P542 element. It is predicted that the use of sensitive detection techniques will indicate that the actual distribution of T. rangeli in America is wider than presumed.

THE OPSONIC INDEX IN THE DIAGNOSIS OF MIXED INFECTION IN PULMONARY TUBERCULOSIS

The importance of mixed infection in tuberculosis is at present a much-disputed question. Some investigators believe that secondary invasion by pyogenic organisms is responsible for practically all the damage done in consumption, while others believe that the tubercle bacillus alone is capable of producing all the pathological changes. Between these two extremes of opinion are found those occupying all possible positions in the middle ground. The reason for this great disagreement of opinion among investigators and clinicians is the inefficiency of the methods used in the diagnosis of mixed infection. Practically all of our data on the subject, up to the present time, have been obtained by: (1) animal experimentation; (2) post-mortem histological and bacteriological examination of the lung; (3) blood cultures before and after death; and (4) sputum examination. The results obtained in animal experimentation are greatly at variance with each other. Sputum inoculated into rabbits and