Inflammatory Response and Activation of Coagulation after COVID-19 Infection

SARS-CoV-2 (COVID-19) infection is responsible for causing a disease with a wide spectrum of clinical presentations. Predisposition to thromboembolic disease due to excessive inflammation is also attributed to the disease. The objective of this study was to characterize the clinical and laboratory aspects of hospitalized patients, in addition to studying the pattern of serum cytokines, and associate them with the occurrence of thromboembolic events.

METHODOLOGY

A retrospective cohort study with 97 COVID-19 patients hospitalized from April to August 2020 in the Triângulo Mineiro macro-region was carried out. A review of medical records was conducted to evaluate the clinical and laboratory aspects and the frequency of thrombosis, as well as the measurement of cytokines, in the groups that presented or did not present a thrombotic event.

RESULTS

There were seven confirmed cases of thrombotic occurrence in the cohort. A reduction in the time of prothrombin activity was observed in the group with thrombosis. Further, 27.8% of all patients had thrombocytopenia. In the group that had thrombotic events, the levels of IL1b, IL-10, and IL2 were higher (p < 0.05).

CONCLUSIONS

In the studied sample, there was an increase in the inflammatory response in patients with thrombotic events, confirmed by the increase in cytokines. Furthermore, in this cohort, a link was observed between the IL-10 percentage and an increased chance of a thrombotic event.

Clinical-Epidemiology Aspect of Inpatients With Moderate or Severe COVID-19 in a Brazilian Macroregion: Disease and Countermeasures

COVID-19, also known as coronavirus disease 2019, is an infectious viral disease caused by SARS-CoV-2, a novel coronavirus. Since its emergence, its epidemiology has been explored; however, for some regions of the world, COVID-19’s behavior, incidence, and impact remain unclear. In continental nations like Brazil, this lack of knowledge results in nonuniform control, prevention, and treatment measures, which can be controversial in some locations. This study aimed to describe the epidemiological profile of patients with COVID-19 in the macroregion of Triângulo Sul in the state of Minas Gerais (MG), Brazil. Between March 25 and October 21, 2020, data were collected and statistically analyzed from 395 hospitalized patients in the city of Uberaba, MG, suspected to have moderate or severe forms of the disease. Of the 395 suspected cases, 82% were confirmed to be positive for COVID-19. The mean age of positive patients was 58.4 years, and 60.76% were male. Following these patients throughout their hospitalization, a mortality rate of 31.3% was observed. In the population positive for COVID-19, the risk of death increased by 4% for each year of the patient’s age. Likewise, the older the patient, the longer their hospitalization and the higher the risk of developing acute respiratory failure. Among the treatments tested in patients, heparin was associated with protection against mortality, and the absence of anticoagulant use was linked to a more than six times greater risk of death. Finally, comorbidities in patients with COVID-19 were positively correlated with increased hospitalization time. In summary, this study revealed that age, presence of comorbidities, length of hospitalization, and drug treatment considerably altered COVID-19’s lethality. To understand infection rates and the factors involved in COVID-19’s lethality, knowledge of the local epidemiology is necessary.

Novel polymorphisms in the promoter region of the perforin gene among distinct Brazilian populations and their functional impact

Cytotoxic T lymphocytes and natural killer cells play a crucial role in eliminating tumour and virus-infected cells. The perforin is a key part of the arsenal that these cells use to destroy their targets. In this study, we characterized single-nucleotide polymorphisms (SNPs) located in the promoter region of the perforin gene among distinct Brazilian ethnic groups. The study was carried out by sequencing this region in three groups: European, African and Asian descents. We demonstrated for the first time the occurrence of three new polymorphisms in the promoter region of gene PRF1: 494A/G (rs78058707), 720G/A (rs75925789) and 1176C/T (rs75183511). Three other SNPs already described in the literature 63A/G (rs35401316), 112A/G (rs10999428) and 1012C/T (rs35069510) were also detected. The SNPs are distributed differently in the ethnic groups studied. The 112G allele was observed at high frequency, especially among Asian descents (48.1%). The 1012T allele was detected only among European descents, the 494G allele only among Asian descents and 1176T allele only in African descents. Based on the association between the polymorphisms described, ten new haplotypes were originated. In functional analysis, we noticed that SNPs present in most common haplotypes cannot induce significant differences in expression levels of perforin alone. In conclusion, this study demonstrates for the first time the existence of three new polymorphisms in perforin promoter and, contrary to what was stated, the presence of these SNPs does not alter the levels of protein expression.

The importance of hemovigilance in the transmission of infectious diseases

Background

Hemovigilance is an organized system of surveillance throughout the transfusion chain intended to evaluate information in order to prevent the appearance or recurrence of adverse reactions related to the use of blood products.

Objective

The aims of this study were to assess the late reporting of incidents related to possible seroconversion in respect to age, marital status and ethnical background, annual variations in late reporting, the number of reports opened and closed, seroconversion of donors and transfusions of blood products within the window period.

Methods

This retrospective, descriptive study used data on blood donations in the blood bank in Uberaba during the period from 2004 to 2011. Some socio-epidemiological characteristics of the donors and serology test results of donors and recipients were analyzed in respect to the late reporting of incidents related to possible seroconversion. The Chi-square test, odds ratio and a regression model were used for statistical analysis.

Results

From 2004 to 2011, the blood bank in Uberaba collected 117,857 blood bags, 284 (0.24%) of which were investigated for late reported incidents. The profile of the donors was less than 29 years old, unmarried and non-Whites. Differences in age (p-value < 0.0001), marital status (p-value = 0.0002) and ethnical background (p-value < 0.0001) were found to be statistically significant. There was no statistical difference between men and women (0.24% and 0.23% respectively; p-value = 0.951). The number of late reported incidents increased until 2008 followed by a downward trend until 2011. There were twelve cases of seroconversion in subsequent donations (seven human immunodeficiency virus, four hepatitis B and one hepatitis C) with proven human immunodeficiency virus infection after screening of only one recipient.

Conclusion

The twelve cases of seroconversion in donors with subsequent infection proven in one recipient underscores the importance of this tool to increase transfusion safety.

Efeito de dois agentes tripanosomicidas, violeta de genciana e WR6026, na preservação de concentrado de plaquetas

Visando verificar a viabilidade do concentrado de plaquetas, após sua preservação com substâncias, que adicionadas ao sangue sejam capazes de destruir o Trypanosoma cruzi, testamos concentrado de plaquetas estocado com a violeta de genciana e a quinolina WR6026. A viabilidade foi avaliada através da contagem do número de plaquetas, da medida do pH e agregação plaquetária com par de agonistas durante seu período de estocagem. Alterações significativas foram observadas nos concentrados plaquetários tratados com violeta de genciana sugerindo comprometimento da viabilidade plaquetária. Com o WR6026 foram observados valores similares aos controles, abrindo perspectivas para o emprego deste sal na quimioprofilaxia da doença de Chagas transfusional, em regiões altamente endêmicas.

The application of latent class analysis for diagnostic test validation of chronic Trypanosoma cruzi infection in blood donors

The main strategy to prevent transfusion-associated Chagas disease is the identification of T. cruzi-infected blood donors by serological screening tests, however there is no perfect serological gold standard. We evaluated an enzyme immunoassay (EIA), an indirect hemaglutination (IHA), and an indirect immunofluorescence (IIF) test for detecting T. cruzi antibodies in Brazilian blood donors. The results were submitted to latent class analysis, and a radioimmunopreciptation (RIPA) test was performed on repeatedly positive samples. Among 1951 donors, 11 (0.56%) were positive by EIA, 6 (0.31%) by IHA and 16 (0.82%) by IIF. Six samples were positive with all tests, while 4 reacted with EIA and IIF. The RIPA was positive in 6 (75.0%), 7 (66.6%), and 4 (54.0%) samples reacting by the EIA, IHA and IIF tests, respectively. The latent class model detected a high sensitivity rate (100%) for the EIA and IIF, and a specificity rate of 99.95% and 99.69% for the EIA and IIF tests, respectively. The probability of being case according to the model was 99.92% when both EIA and IIF were positive, and 100% for the association of EIA, IIF, and IHA.

Chagas infection transmission control: situation of transfusional transmission in Brazil and other countries of Latin America

The transmission of the transfusion-associated Chagas disease is an important mechanism of its dissemination in several Latin American countries. The transmission risk depends on five factors: prevalence of infection in blood donors, degree of serological coverage, sensibility of used tests, safety of obtained results and infection risk. The Southern Cone Iniciative set off by the Pan-American Health Organization, in 1991, is contributing to the implementation of blood law in each endemic country, and to reduce the risk of transfusional transmission of this horrible disease. Despite the clear improvement of Brasilian hemotherapy after 1980 (with the creation of the Blood National Program - Pró-Sangue) and the significant reduction of the chagasic infection among its blood donors; socio-economic, politic and cultural unlevels, prevent it from reaching the necessary universality and security. In order to assure both, the Brazilian Ministry of Health decided to restructure its blood system. In May, 1998, a great program was launched, to reach a specific goal: Blood - 100% with quality safety in all its process until 2003. It was divided in 12 projects, intends to guarantee the quality and self sufficiency in blood and hemoderivates.

Removal of Trypanosoma cruzi by white cell-reduction filters: an electronmicroscopic study

White cell (WBC)-reduction filters have been shown to be effective in removing infectious agents from infected blood products. In this study, the mechanisms of Trypanosoma cruzi (T. cruzi) retention by WBC-reduction filters were assessed. Human packed red blood cell (PRBC) and platelet concentrate (PC) samples were contaminated with T. cruzi organisms (Y strain; 3.4 x 10(6)/ml), and then filtered using WBC-reduction experimental filters that provided about 3 log10 WBC removal. Transmission electron microscopy sections showed that T. cruzi parasites were removed from contaminated PRBC and PC samples primarily by mechanical mechanism without interacting with filter fibers or blood cells. In addition, we found that T. cruzi parasites were also removed by a direct fiber adhesion. These data indicate that T. cruzi parasites are removed from infected blood not only by mechanical mechanism but also by biological mechanism probably mediated by parasite surface proteins.

Strategies for prevention of transfusion-associated Chagas' disease

Available epidemiological data indicate that Chagas' disease, a zoonosis caused by the flagellate protozoan parasite T cruzi, is a very important medical and social problem in Latin America. More than 60% of T cruzi-infected individuals have migrated to urban areas, in both endemic and nonendemic countries. Thus, with the implementation and maintenance of regular vector control programs in some countries, allogeneic blood transfusions have been the main mechanism for the continuation of this endemy. The risk of infection after transfusion of a unit of T cruzi-infected blood product depends mainly on the amount of blood transfused, parasite concentration in the infected transfused blood unit, and the recipient's immunological status. Current strategies to prevent transfusion-associated Chagas' disease include the identification of T cruzi-infected blood donors by predonation questionnaire, serological tests for T cruzi antibodies, and the treatment of the blood collected with gentian violet. Because T cruzi infection is lifelong, and most infected persons are asymptomatic, the identification of high-risk blood donors by a predonation questionnaire is relevant in nonendemic countries but this strategy seems to be of limited usefulness for donor deferral in endemic areas. Because T cruzi antigens are shared by other parasites, the serological diagnosis of T cruzi infection is complex yielding both false-positive and false-negative results. Although sensitive, the tests currently available for the serodiagnosis of T cruzi infection lack specificity and a more specific, confirmatory test is still needed for the routine confirmation of T cruzi chronic infection. In areas of high endemicity or where serological screening is not available, the risk of T cruzi transmission by blood transfusion may be reduced by the addition of gentian violet to the collected blood. The use of gentian violet, alone or combined with ascorbic acid and light, effectively inactivate T cruzi present in donor blood; however, the long-term toxicity of this agent for blood recipients is still an open issue. In conclusion, the prevention of TA-CD is based on various strategies that are not mutually exclusive. Blood donor education, identification of putatively infectious blood donors by questionnaire or serological screening tests, and methods of parasite inactivation may significantly reduce the transmission of T cruzi by allogeneic blood transfusions.

Treatment of T. cruzi infected human platelet concentrates with aminomethyltrimethyl psoralen (AMT) and ultraviolet A (UV-A) light: preliminary results

The present measures adopted to prevent transfusion-associated Chagas' disease include screening of blood donors, and/or the inactivation of T. cruzi in collected blood using gentian violet (GV), as a trypanocidal agent. In this study, we investigated the efficacy of the combined use of AMT and UV-A in inactivating T. cruzi in infected human platelet concentrates. Human platelet concentrates were infected with T. cruzi (2 x 10(8)/ml) of the Y strain, transfered to PL 269 (Fenwal Laboratories) containers, and treated with GV (250 micrograms/ml), and ascorbic acid (1 mg/ml); GV, ascorbic acid and UV-A; GV and UV-A; AMT (40 microG/ml) and ascorbic acid; AMT, ascorbic acid and UV-A; AMT and UV-A; UV-A alone; and untreated (control). All UV-A treated platelet concentrates were exposed to UV-A doses of 24, 92, 184, 276, 368 and 644 kJ/m2, and the microscopical research of active T. cruzi was performed, using the microhematocrit technique, 1, 6 and 24 hours after each treatment. A high number of active forms of T. cruzi was observed in all condictions, except when GV was used as the trypanocidal agent, providing evidence of the failure of AMT and UV-A in inactivating T. cruzi in infected human platelet concentrates.

Prevention of transfusion-associated Chagas' disease: efficacy of white cell-reduction filters in removing Trypanosoma cruzi from infected blood

BACKGROUND

Transfusion-associated Chagas' disease (TA-CD) is a worldwide problem. Measures adopted to prevent TA-CD include the clinical and serologic screening of blood donors and/or the inactivation of Trypanosoma cruzi present in collected blood, using gentian violet as the trypanocidal agent. This study investigated the efficacy of white cell-reduction filters in removing T. cruzi from infected blood.

STUDY DESIGN AND METHODS

Human blood was contaminated with 2 or 150 T. cruzi parasites per mL and then left unfiltered or filtered with white cell-reduction filters that provided either 2, 3, or 6 log10 white cell removal. The efficacy of the parasite removal of these filters was evaluated by microscopic enumeration of active forms of T. cruzi both in vivo and in vitro. The in vivo experiments were done in Swiss mice that had been intraperitoneally inoculated with T. cruzi-infected human blood. The in vitro experiments were performed with fresh human blood that had been deliberately contaminated with T. cruzi.

RESULTS

The number of parasites seen in mice inoculated with unfiltered blood containing 2 or 150 parasites per mL was significantly higher than the number of parasites seen in mice inoculated with blood from the same sample, but filtered with white cell-reduction filters providing 3 or 6 log10 white cell removal. Fifty to 70 percent of the mice given T. cruzi-infected (2 parasites/mL) filtered blood did not develop T. cruzi infection. In vitro, the use of white cell-reduction filters, providing 2, 3, or 6 log10 white cell removal, significantly reduced the number of parasites seen in culture.

CONCLUSION

The present experimental data provide evidence that white cell-reduction filters are effective in reducing the number of parasites in T. cruzi-infected blood and that this efficacy depends, in part, on the concentration of parasites in the artificially infected blood. Properly designed clinical studies of known carriers of T. cruzi must be conducted to determine whether the use of white cell-reduction filters may be an alternative method of reducing the incidence of TA-CD.

Prevention of transfusion-associated Chagas' disease by sterilization of Trypanosoma cruzi-infected blood with gentian violet, ascorbic acid, and light

BACKGROUND

Allogeneic blood transfusions are the second most frequent route of Chagas' disease transmission in countries where the disease is endemic. The prevention of transfusion-associated Chagas' disease has been attempted through clinical and serologic screening of blood donors and/or by the addition of trypanomicidal substances such as gentian violet (GV) to stored blood for 24 hours. The present study describes an alternative method of chemoprophylaxis of transfusion-associated Chagas' disease that reduces the sterilization time by using a combination of low-concentration GV, ascorbic acid (AA), and photoradiation with visible light.

STUDY DESIGN AND METHODS

To better reproduce the conditions of blood transfusion in developing areas, normal human blood was collected in blood collection bags, infected with different concentrations of Trypanosoma cruzi, and treated with GV, AA, and photoradiation. Mice were then inoculated with the T. cruzi-infected human blood that had been stored at different incubation intervals. Active parasites were sought in mouse blood for parasitologic diagnosis and serologic evaluation (mice inoculation, blood culture, and indirect immunofluorescence).

RESULTS

The association of GV (250 micrograms/mL), and photoradiation with visible light (75W) sterilized T. cruzi-infected blood even after treatment for less than 30 minutes and even when chagasic blood was treated with low-concentration GV (62.5 micrograms/mL for 30 min). Moreover, the trypanomicidal activity of GV associated with AA and photoradiation with visible light was found even when blood was infected with a 10-fold parasite concentration.

CONCLUSIONS

The proposed alternative prophylactic method is reproducible, easy to perform, and inexpensive, and it may have practical importance in endemic areas where serologic screening of donor blood is not always available. In addition, the reduction of the GV trypanomicidal concentration might further minimize the potential for GV-related side effects.

[Multiple neoplasms after a well succeeded treatment of Hodgkin's disease]

The authors refer to a 21-year-old Caucasian (white) woman, who in 1977 presented fever and cervical and axillary adenopathy, whose biopsy showed nodular sclerosis Hodgkin's Disease, stage IIIB. The patient received six chemotherapy cycles associated with immunotherapy and supplemented with radiation therapy with good response. RESULTS--In 1985, after routine gynaecological examination and a hysterectomy, cervical intraepithelial neoplasia grade 3 (CIN 3) and atypic leiomyoma of the uterine body were diagnosed. Five years later, biopsies diagnosed invasive duct carcinoma in the right breast and homolateral axillary and cervical nodes. The patient was submitted to chemo and radiation therapy and died nine months later. CONCLUSION--The possibility of later occurrence of a second or multiple new malignancies in patients successfully treated for Hodgkin's Disease points out the need for a more complete long-term follow-up, including periodic mammography.

[Hemotherapy and transfusional Chagas' disease in Brazil]

With the increased presence of Chagas' disease in urban areas and the rising importance of transfusional transmission of Trypanosoma cruzi, a proper and realistic approach to hemotherapeutic treatment has become crucial in Brazil. Bringing together data from various institutions, this study analyzed hemotherapy and the problem of transfusional Chagas' disease in 850 Brazilian municipalities from 1988 to 1989. It was found that some type of hemotherapy was practiced in 68.8% of these municipalities at the time, this practice being qualitatively and quantitatively proportional to the population size of the municipality. The official blood bank system supplied the blood used in 13% of these services. In relation to prevention of the main diseases transmissible by transfusion, prior screening of donors was carried out by 75.2% of the services for syphilis, 65.4% for hepatitis, 53.8% for AIDS, and 66.9% for Chagas' disease. These percentages vary by region and by size of the municipality. The majority of donors are classified as voluntary, with only 2% categorized as paid donors. In the case of Chagas' disease, most services used only one serologic technique to screen donors, most commonly hemagglutination or immunofluorescence, while only 10.3% of services had previous experience with chemoprophylaxis using gentian violet. The proportion of potential donors with positive serology for anti-Trypanosoma cruzi antibodies was around 1%. These data were confirmed by information from blood banks and Brazilian hemotherapy professionals.

[Control of hemotherapy and transfusional Chagas disease: 1988 and 1990]

An inquiry with the objective of bringing the study of the hemotherapy situation in the state of S. Paulo, up-to-date was undertaken in 1990 and compared with that carried out in 1988. In 1990 research was undertaken in 62 counties, 48 of which performed blood transfusions through 104 services, with hemocenter participation in 13.5% of these latter. In 1988 the respective figures were 57, 40, 71 and 8.5%. The number of donors and transfusions and prevalence of serological positivity for Chagas' disease were, respectively: 105,170; 79,544 and 1.24%, while in 1988 the corresponding numbers were: 51,614; 49,211 and 1.52%. Evaluating the serological selection it was found that the following percentages of the services performed serological tests: for Chagas' disease (94.2%), syphilis (94.2%), hepatitis (94.2%), HIV (92.3%) and malaria (20.2%) while in 1988 only 69.0%; 70.4%; 67.6%, 63.4% and 16.9%, respectively, of the services utilized these same tests. In respect of the serological trial specific for Chagas' disease the results were: complement fixation-4.9%; latex-4.0%; indirect immunofluoresce-80%; direct hemaglutination-24.0%, indirect hemaglutination-69.0% and ELISA-59.0% of all services. In the preceding inquiry only 14.3% of the services performed the ELISA test, and complement fixation was utilized in 28.6%. The results show that the services are utilizing ever more sensitive techniques in the serological routine. Further it was observed that in 1988, 77.6% of all the services studied used only one technique for the diagnosis of Chagas' disease while in 1990 92.9% utilized two or more different techniques. It is concluded that the quality of the hemotherapy undertaken in the state of S. Paulo has improved significantly.