Antígenos del sistema sanguíneo ABO como factor de riesgo para la gravedad de la infección por SARS-CoV-2 / Blood system ABO antigens as risk factor for severity of SARS-CoV-2 infection

Resumen Introducción: Se desconoce si existe una influencia del sistema sanguíneo ABO en susceptibilidad y gravedad de la enfermedad. Objetivo: Analizar si existe una asociación entre los antígenos del sistema ABO y la susceptibilidad y gravedad de la infección por SARS-CoV-2. Material y métodos: Se compararon las frecuencias de los antígenos del sistema ABO en 73 casos confirmados de infección por SARS-CoV-2 y 52 donadores clínicamente sanos. La gravedad de la infección se evaluó comparando la frecuencia de los antígenos por gravedad de la enfermedad y la mortalidad. Resultados: El riesgo de padecer infección por SARS-CoV-2 se incrementa en sujetos con antígeno A vs los no-A (OR=1.45; IC95 %:1.061-1.921). El fenotipo sanguíneo O disminuye el riesgo de padecer infección por SARS-CoV-2 (OR=0.686; IC95 %: 0.522-0.903). No se encontraron diferencias entre la gravedad de la enfermedad. En los pacientes graves, el riesgo de mortalidad se incrementó en sujetos con antígeno A vs los no-A (OR= 3.34; IC95 %: 1.417-8.159). Conclusión: El grupo sanguíneo A es un factor de riesgo para padecer infección por SARS-CoV-2, no así en la gravedad de la enfermedad, pero en los pacientes graves fue un factor de riesgo para la mortalidad.

Abstract Introduction: Whether there is an influence of the ABO blood system on susceptibility to the disease and its severity is unknown. Objective: To analyze if there is an association between the ABO blood system phenotypes and susceptibility to SARS-CoV-2 infection and its severity. Material and methods: The frequency of ABO antigens was compared in 73 confirmed cases of SARS-CoV-2 infection and 52 clinically healthy donors. The severity of the infection was evaluated by comparing the frequency of antigens by severity of the disease and mortality. Results: The risk of SARS-CoV-2 infection is increased in subjects with antigen A vs non-A subjects (OR=1.45; 95 %: 1.061-1.921). Blood phenotype O decreases the risk of SARS-CoV-2 infection (OR= 0.686; 95 % CI: 0.522-0.903). No differences were found regarding disease severity. The mortality risk is increased in subjects antigen A vs non-A (OR= 3.34; 95% IC: 1.417-8.159). Conclusion: Blood group A is a risk factor for SARS-CoV-2 infection, but not for disease severity, although in critically ill patients it is a risk factor for mortality.

Intracerebral hemorrhage in children

Intracerebral hemorrhage [ICH] in children is relatively less common as compared to adults. It could be traumatic or spontaneous. There are limited studies about ICH in children. In this study, we analyze the etiology, clinical features, management options and outcome assessment in this population. All patients with intracerebral hemorrhage under 18 years of age admitted to the neurosurgery department; Alexandria University Main Hospital and Medical Research Institute over a period of one year [June 2008-May 2009] were subjected to clinical examination, laboratory and radiological investigations and the cause of hemorrhage was determined. Thirty patients with ICH were included in this study. Age of patients ranged from one month to 17.5 years with a higher predilection in males. Presenting features were symptoms of raised intracranial pressure [60%], deterioration in sensorium [46%], limb weakness [36%] and seizures [30.0%]. Trauma was the most common cause of ICH and was found in 13 patients [43%], followed by bleeding diathesis in nine patients [30%], arteriovenous malformation [AVM] in five patients [17%], intracranial tumor in two patients and an aneurysm in one patient. Treatment modalities consisted of: hematoma evacuation, excision of AVM, AVM emobilization, aneurysm clipping, tumor excision, and conservative management. Eleven patients were treated conservatively and 19 patients were treated surgically. The outcome showed: good recovery in 14[47%], fair recovery in seven [23%], poor recovery in seven [23%], and death in two patients [7%]. Trauma is the leading cause of ICH in children. Bleeding diathesis and AVM come next. The initial neurological status of patients, the size, location and underlying pathophysiology of the hematoma are the most important determinants of patient outcome. Intracerebral hemorrhage due to bleeding diathesis was generally associated with a better outcome

A high corticosterone/DHEA-s ratio in young rats infected with Trypanosoma cruzi is associated with increased susceptibility

We have previously established that young male rats are more susceptible to the effects of Trypanosoma cruzi infection than adult rats. To explore underlying age-associated differences in disease outcome, we simultaneously assessed hormone levels and cytokine release throughout the acute infection period in young and adult rats infected with T. cruzi. Young rats were inoculated with 1 x 10(6) and adult rats with 7 x 10(6) blood trypomastigotes, according to their relative body weight. At zero, seven, 14, 21 and 28 days after infection, blood was collected for the determination of gonadal and adrenal hormones, tumor necrosis factor α (TNF-α), interleukin (IL)-10 and specific IgM and IgG subtypes. Young animals displayed significantly higher parasitaemia values and an endocrine pattern that was characterised by elevated values in corticosterone (CT) and the CT/dehydroepiandrosterone-sulfate ratio, which favours immunosuppression and susceptibility. In contrast, adult male rats were able to restrict the parasite burden, which likely resulted from increased IgG antibody synthesis and oestradiol levels. Adult rats also showed a reduced TNF-α/IL-10 ratio and less tissue damage. We conclude that young animals exhibited increased vulnerability to T. cruzi infection compared with adults and this is associated with an unsuitable immunoendocrine milieu.

Dermatophytosis: association between ABO blood groups and reactivity to the trichophytin

The authors investigated the relationship between dermatophytosis and ABO blood groups through blood typing, identification of isolated dermatophytes and specific cellular immune response of 40 individuals carriers of this mycosis. They verified that the fungus Trichophyton rubrum, isolated from 54.5 percent of the patients, was more frequent in individuals belonging to blood group A. The cellular immune response, evaluated through the trichophytin antigen, was positive in 25 percent of the studied patients; the presence of immediate reactions (30 minutes) was verified in 35 percent. The blood group distribution among patients with dermatophytosis and control groups was, respectively: 47.5 percent X 36 percent in group A, 40 percent X 50 percent in group O, 12.5 percent X 11 percent in group B. Even though the authors have found a higher number of patients belonging to blood group A infected by T. rubrum, these results suggest that there is no statistical evidence that these individuals are more susceptible to dermatophytosis

Susceptibility to hepatitis A virus infection among chronic liver disease patients and healthy blood donors in Thailand.

Due to improvements in socio-economic and sanitation conditions, Thailand has undergone a change from hyperendemicity to intermediate endemicity for hepatitis A virus infection, leaving a large part of the adult population without immunity. At the same time, the country is still highly endemic for hepatitis B and especially in the northeast, hepatitis C virus infection both of which when acquired during infancy or early childhood exhibit a strong tendency to turn towards chronic liver disease, although in particular with hepatitis B virus the asymptomatic carrier state is also rather common. As no cross-immunity exists between any of these viruses, double or triple infections do occur, a situation where previously acquired immunity to HAV becomes crucial as double infections have been shown to take a more severe or even fatal course. In the present study, we investigated 820 HBV- and/or HCV-related chronic liver disease (CLD) patients and 195 blood donors, both groups divided by 10-year age intervals, for the prevalence of anti-HAV. The results showed the same age dependence of immunity for all groups tested as can be expected for an area of intermediate endemicity, in that approximately 50% of those between 21 and 30 years of age had acquired anti-HAV. These findings indicate the immune response to HAV infection not to be altered by chronic infection with either HBV or HCV. Hence, vaccination against HAV should be considered, particularly in anti-HAV-negative patients with CLD.

Dermatophytosis: association between ABO blood groups and reactivity to the trichophytin / Dermatofitose: associação entre grupos sanguíneos ABO e reatividade à tricofitina

The authors investigated the relationship between dermatophytosis and ABO blood groups through blood typing, identification of isolated dermatophytes and specific cellular immune response of 40 individuals carriers of this mycosis. They verified that the fungus Trichophyton rubrum, isolated from 54.5 percent of the patients, was more frequent in individuals belonging to blood group A. The cellular immune response, evaluated through the trichophytin antigen, was positive in 25 percent of the studied patients; the presence of immediate reactions (30 minutes) was verified in 35 percent. The blood group distribution among patients with dermatophytosis and control groups was, respectively: 47.5 percent X 36 percent in group A, 40 percent X 50 percent in group O, 12.5 percent X 11 percent in group B. Even though the authors have found a higher number of patients belonging to blood group A infected by T. rubrum, these results suggest that there is no statistical evidence that these individuals are more susceptible to dermatophytosis

Os autores investigaram a relação entre dermatofitose e grupos sanguíneos ABO por meio da tipagem sanguínea, identificação de dermatófitos isolados e resposta imune celular específica de 40 indivíduos portadores dessa micose. Verificaram que o fungo Trichophyton rubrum, isolado de 54,5 por cento dos pacientes, era mais frequente em indivíduos pertencentes ao grupo sanguíneo A. A resposta imune celular, avaliada pelo antígeno tricofitina, foi positiva em 25 por cento dos pacientes estudados; a presença de reações imediatas (30 minutos) foi verificada em 35 por cento. A distribuição do grupo sanguíneo entre os pacientes com dermatofitose e grupos controle foi, respectivamente: 47,5 por cento X 36 por cento no grupo A, 40 por cento X 50 por cento no grupo O, 12,5 por cento X 11 por cento no grupo B. Mesmo que os autores encontraram um maior número de pacientes pertencentes ao grupo sanguíneo A infectado por T. rubrum, estes resultados sugerem que não há evidências estatísticas de que esses indivíduos sejam mais suscetíveis à dermatofitose