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1.
Chest ; 160(1): e39-e44, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34246387

RESUMO

CASE PRESENTATION: A 65-year-old man presented with shortness of breath, gradually worsening for the previous 2 weeks, associated with dry cough, sore throat, and diarrhea. He denied fever, chills, chest pain, abdominal pain, nausea, or vomiting. He did not have any sick contacts or travel history outside of Michigan. His medical history included hypertension, diabetes mellitus, chronic kidney disease, morbid obesity, paroxysmal atrial fibrillation, and tobacco use. He was taking amiodarone, carvedilol, furosemide, pregabalin, and insulin. The patient appeared to be in mild respiratory distress. He was afebrile and had saturation at 93% on 3 L of oxygen, heart rate of 105 beats/min, BP of 145/99 mm Hg, and respiratory rate of 18 breaths/min. On auscultation, there were crackles on bilateral lung bases and chronic bilateral leg swelling with hyperpigmented changes. His WBC count was 6.0 K/cumm (3.5 to 10.6 K/cumm) with absolute lymphocyte count 0.7 K/cumm (1.0 to 3.8 K/cumm); serum creatinine was 2.81 mg/dL (0.7 to 1.3 mg/dL). He had elevated inflammatory markers (serum ferritin, C-reactive protein, lactate dehydrogenase, D-dimer, and creatinine phosphokinase). Chest radiography showed bilateral pulmonary opacities that were suggestive of multifocal pneumonia (Fig 1). Nasopharyngeal swab for SARS-CoV-2 was positive. Therapy was started with ceftriaxone, doxycycline, hydroxychloroquine, and methylprednisolone 1 mg/kg IV for 3 days. By day 3 of hospitalization, he required endotracheal intubation, vasopressor support, and continuous renal replacement. Blood cultures were negative; respiratory cultures revealed only normal oral flora, so antibiotic therapy was discontinued. On day 10, WBC count increased to 28 K/cumm, and chest radiography showed persistent bilateral opacities with left lower lobe consolidation. Repeat respiratory cultures grew Pseudomonas aeruginosa (Table 1). Antibiotic therapy with IV meropenem was started. His condition steadily improved; eventually by day 20, he was off vasopressors and was extubated. However, on day 23, he experienced significant hemoptysis that required reintubation and vasopressor support.


Assuntos
Aspergillus niger/isolamento & purificação , COVID-19 , Hemoptise , Aspergilose Pulmonar Invasiva , Pseudomonas aeruginosa/isolamento & purificação , SARS-CoV-2/isolamento & purificação , Superinfecção , Voriconazol/administração & dosagem , Idoso , Antifúngicos/administração & dosagem , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/fisiopatologia , COVID-19/terapia , Deterioração Clínica , Estado Terminal/terapia , Procedimentos Clínicos , Diagnóstico Diferencial , Hemoptise/diagnóstico , Hemoptise/etiologia , Hemoptise/terapia , Humanos , Aspergilose Pulmonar Invasiva/complicações , Aspergilose Pulmonar Invasiva/diagnóstico , Aspergilose Pulmonar Invasiva/fisiopatologia , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Masculino , Radiografia Torácica/métodos , Respiração Artificial/métodos , Superinfecção/diagnóstico , Superinfecção/microbiologia , Superinfecção/fisiopatologia , Superinfecção/terapia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
2.
Chest ; 158(5): e233-e236, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33160543

RESUMO

CASE PRESENTATION: A 28-year-old woman G1P0 at 22 weeks of gestation and with no significant medical history presented to the ED complaining of worsening dyspnea and right-sided pleuritic chest pain. Symptoms started 2 weeks before presentation, with minimal productive cough and dyspnea on exertion. One week after the initial symptoms, the patient started noticing right-sided chest and shoulder pain along with subjective fevers and night sweats. She denied hemoptysis, weight loss, abdominal pain, diarrhea, nausea, vomiting, arthralgia, or rash. Her pregnancy had so far been uncomplicated. The patient did not use tobacco, alcohol, or recreational drugs. She worked at a daycare center but denied any particular sick contacts. She moved to the United States 7 years ago from Sudan and denied any recent travel.


Assuntos
Albendazol/administração & dosagem , Equinococose Pulmonar , Abscesso Pulmonar/diagnóstico , Derrame Pleural , Complicações na Gravidez , Pseudomonas aeruginosa/isolamento & purificação , Superinfecção , Toracentese/métodos , Adulto , Anti-Helmínticos/administração & dosagem , Diagnóstico Diferencial , Drenagem/métodos , Equinococose Pulmonar/complicações , Equinococose Pulmonar/diagnóstico , Equinococose Pulmonar/tratamento farmacológico , Feminino , Humanos , Derrame Pleural/diagnóstico , Derrame Pleural/etiologia , Derrame Pleural/fisiopatologia , Derrame Pleural/cirurgia , Gravidez , Complicações na Gravidez/microbiologia , Complicações na Gravidez/fisiopatologia , Complicações na Gravidez/terapia , Resultado da Gravidez , Superinfecção/diagnóstico , Superinfecção/fisiopatologia , Toracoscopia/métodos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
3.
J Virol ; 87(14): 8145-57, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23678165

RESUMO

We have developed a novel in vivo superinfection fitness assay to examine superinfection dynamics and the role of virulence in superinfection fitness. This assay involves controlled, sequential infections of a natural vertebrate host, Oncorhynchus mykiss (rainbow trout), with variants of a coevolved viral pathogen, infectious hematopoietic necrosis virus (IHNV). Intervals between infections ranged from 12 h to 7 days, and both frequency of superinfection and viral replication levels were examined. Using virus genotype pairs of equal and unequal virulence, we observed that superinfection generally occurred with decreasing frequency as the interval between exposures to each genotype increased. For both the equal-virulence and unequal-virulence genotype pairs, the frequency of superinfection in most cases was the same regardless of which genotype was used in the primary exposure. The ability to replicate in the context of superinfection also did not differ between the genotypes of equal or unequal virulence tested here. For both genotype pairs, the mean viral load of the secondary virus was significantly reduced in superinfection while primary virus replication was unaffected. Our results demonstrate, for the two genotype pairs examined, that superinfection restriction does occur for IHNV and that higher virulence did not correlate with a significant difference in superinfection fitness. To our knowledge, this is the first assay to examine the role of virulence of an RNA virus in determining superinfection fitness dynamics within a natural vertebrate host.


Assuntos
Vírus da Necrose Hematopoética Infecciosa/genética , Vírus da Necrose Hematopoética Infecciosa/patogenicidade , Superinfecção/fisiopatologia , Superinfecção/virologia , Animais , Genótipo , Modelos Lineares , Oncorhynchus mykiss , Fatores de Tempo , Carga Viral , Virulência , Replicação Viral/fisiologia
4.
PLoS Pathog ; 4(10): e1000184, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18949036

RESUMO

A number of human infections are characterized by the presence of more than one bacterial species and are defined as polymicrobial diseases. Methods for the analysis of the complex biological interactions in mixed infections with a large number of microorganisms are limited and do not effectively determine the contribution of each bacterial species to the pathogenesis of the polymicrobial community. We have developed a novel Drosophila melanogaster infection model to study microbe-microbe interactions and polymicrobe-host interactions. Using this infection model, we examined the interaction of 40 oropharyngeal isolates with Pseudomonas aeruginosa. We observe three classes of microorganisms, one of which acts synergistically with the principal pathogen, while being avirulent or even beneficial on its own. This synergy involves microbe-microbe interactions that result in the modulation of P. aeruginosa virulence factor gene expression within infected Drosophila. The host innate immune response to these natural-route polymicrobial infections is complex and characterized by additive, suppressive, and synergistic transcriptional activation of antimicrobial peptide genes. The polymicrobial infection model was used to differentiate the bacterial flora in cystic fibrosis (CF) sputum, revealing that a large proportion of the organisms in CF airways has the ability to influence the outcome of an infection when in combination with the principal CF pathogen P. aeruginosa.


Assuntos
Modelos Animais de Doenças , Drosophila/microbiologia , Interações Hospedeiro-Patógeno/fisiologia , Superinfecção/microbiologia , Superinfecção/fisiopatologia , Animais , Antibiose/fisiologia , Análise por Conglomerados , Contagem de Colônia Microbiana , Drosophila/genética , Drosophila/imunologia , Drosophila/fisiologia , Imunidade Inata/genética , Imunidade Inata/fisiologia , Microscopia de Fluorescência , Infecções por Neisseriaceae/microbiologia , Infecções por Neisseriaceae/mortalidade , Infecções por Neisseriaceae/patologia , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/mortalidade , Infecções por Pseudomonas/patologia , Infecções por Pseudomonas/fisiopatologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/patogenicidade , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/mortalidade , Infecções Estreptocócicas/patologia , Superinfecção/mortalidade , Superinfecção/patologia , Análise de Sobrevida
7.
Dig Dis Sci ; 49(2): 281-8, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15104371

RESUMO

We investigated the virological impact of acute hepatitis C virus (HCV) superinfection on two patients with hepatitis B virus (HBV)-related cirrhosis. In both patients, chronic HBV-infection persisted while acute HCV infection resolved spontaneously. HBV DNA was transiently suppressed in both patients but increased with HCV resolution. In Case 1 (HBeAg-positive; wild type of basic core promoter [BCP] and precore [PreC]), fluctuations of HBV DNA and HBeAg state were accompanied by mutations of the BCP and PreC. In Case 2 (HBeAg-negative; mutant type of the BCP and PreC), changes in HBV DNA levels were associated with mutations of PreC. In both cases, mutant PreC changed to the wild type upon HCV resolution, and no nucleotide A insertion at position 193 of the HCV 5'-untranslated region, which influences HCV spontaneous clearance, was detected. The putative DNA-binding motif in the HCV core was SPRG (amino acids 99-102). HCV infection was associated with changes in the nucleotide sequences of the binding site for the nuclear receptor family in HBV enhancer 2 (Enh2) including the BCP rather than Enh1. Our results suggest that the impact of acute HCV infection on chronic HBV infection varies according to HBV virological state.


Assuntos
Hepatite B/complicações , Hepatite C/complicações , Hepatite C/fisiopatologia , Cirrose Hepática/virologia , Superinfecção/complicações , Superinfecção/fisiopatologia , Regiões 5' não Traduzidas , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Sequência de Bases , Biomarcadores/análise , Elementos Facilitadores Genéticos/genética , Feminino , Hepacivirus/genética , Hepatite B/metabolismo , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Proteínas do Core Viral/genética
8.
Sex Health ; 1(4): 239-50, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-16335754

RESUMO

As the human immunodeficiency virus (HIV) pandemic progresses, an increasing number of recombinant viruses have been identified and in many geographical regions they are now the predominating strain. These recombinants are formed when an individual has acquired a co-infection or superinfection with more than one HIV-1 strain or subtype. Thus, dually infected individuals provide opportunities for studying HIV recombinants and viral interactions between infecting strains in vivo. The possible epidemiological, clinical and therapeutic implications of dual infections and recombination are many. Recombination may result in the emergence of more pathogenic and virulent HIV strains with altered fitness, tropism, and resistance to multiple drugs, and may hamper the development of subtype-based vaccines. This review is aimed at providing a more thorough understanding of dual infections (both co-infection and super-infection) and the possible consequences of the emergence of recombinant HIV-1 strains.


Assuntos
Infecções por HIV/virologia , HIV/genética , Recombinação Genética , Superinfecção/virologia , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Farmacorresistência Viral/genética , Saúde Global , HIV/classificação , HIV/patogenicidade , Infecções por HIV/fisiopatologia , Humanos , Fatores de Risco , Superinfecção/fisiopatologia
9.
Zhonghua Nei Ke Za Zhi ; 41(10): 656-9, 2002 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-12485528

RESUMO

OBJECTIVE: To observe the effect of hepatitis E virus (HEV) superinfection on hepatic lesion and hepatitis B virus (HBV) replication in patients with chronic hepatitis B (CHB). METHODS: Totally 122 patients with CHB were enrolled in this study. They were tested for anti-HEV IgM and IgG in serum, amount of HBV DNA in serum and liver tissue obtained by liver biopsy and HBcAg expression in liver tissue. Other parameters such as ALT, total bilirubin (TBil), albumin (A) and globulin (G), gamma-electrophoretic protein (gamma-EP), prothrombin activity (PTA) were also measured. 21 of the 122 patients (17.2%) were found to have HEV superinfection and the remaining 101 were not. Repeat liver biopsy was performed after 1 year in 7 patients with HEV superinfection and 14 patients without. Moreover, HBV DNA amount in serum from 8 HBeAg negative patients with HEV superinfection were tested dynamically in acute and recovery stage of HEV infection. RESULTS: Comparison of the data from the 21 patients with HEV superinfection and 101 without showed that there was no significant difference in the level of A/G ratio (1.74 +/- 0.50 vs. 1.83 +/- 0.37) and gamma-EP [(24.18 +/- 6.36)% vs. (22.27 +/- 4.59)%, P > 0.05]. However, the level of ALT [(244.61 +/- 81.07) U/L vs. (143.87 +/- 47.69) U/L] and TBil [(88.24 +/- 28.54) micro mol/L vs. (46.16 +/- 17.13) micro mol/L] was significantly higher (P < 0.05), but that of PTA lower in the group with HEV superinfection than in the group without superinfection [(58.57 +/- 17.44)% vs. (72.52 +/- 12.25)%, P < 0.05]. So were the amount of HBV DNA in serum [(5.45 +/- 1.86) copies/ml vs. (6.59 +/- 1.28) copies/ml, P < 0.05] and liver tissue [(6.96 +/- 2.52) copies/g vs. (8.47 +/- 1.79) copies/g, P < 0.05] as well as HBeAg and HBcAg positive rates (8/21 vs. 64/101; 9/21 vs. 67/101, P < 0.05). Pathologically, the hepatic inflammatory activity was more severer in patients with HEV superinfection, but the severity of fibrosis was not significantly different. There was no difference in the severity of inflammatory activity and stage of fibrosis between the 7 patients with HEV superinfection and the 14 patients without as well as before and after 1 year of treatment. The amount of HBV DNA and HBeAg positive rate in serum from recovery stage of HEV infection were higher than those of acute stage. CONCLUSIONS: HEV superinfection leads to activation of hepatic pathological changes and worsens the inflammatory activity. Moreover, HEV superinfection inhibits HBV replication, but it may not be long-lasting.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica/complicações , Vírus da Hepatite E , Hepatite E/complicações , Superinfecção/patologia , Adulto , Feminino , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/patologia , Hepatite E/sangue , Hepatite E/patologia , Humanos , Inflamação/etiologia , Testes de Função Hepática , Masculino , Superinfecção/sangue , Superinfecção/fisiopatologia , Superinfecção/virologia
10.
Clin Infect Dis ; 34(8): 1108-14, 2002 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11915000

RESUMO

Superinfection with multiple strains or subtypes of the human and simian immunodeficiency viruses has been documented. Recent increases in the prevalences of both unprotected anal intercourse and sexually transmitted diseases among men who have sex with men indicate that these men continue to practice unsafe sex and, therefore, are at risk for superinfection with the human immunodeficiency virus (HIV). Recurrent exposure to HIV among seropositive individuals who engage in high-risk behaviors can have serious consequences, because superinfection is a necessary first step for viral recombination to occur. Recombination may produce more virulent viruses, drug-resistant viruses, or viruses with altered cell tropism. Additionally, recombinant viruses and superinfection can accelerate disease progression and increase the likelihood of sexual transmission by increasing virus load in the blood and genital tract. The extent of superinfection and recombination in persons living with HIV is unknown. The implications of HIV superinfection and the generation of recombinant viruses are discussed.


Assuntos
Infecções por HIV/fisiopatologia , HIV/genética , Recombinação Genética , Superinfecção/fisiopatologia , Previsões , Variação Genética , HIV/classificação , HIV/patogenicidade , Infecções por HIV/virologia , Humanos , Fatores de Risco , Infecções Sexualmente Transmissíveis/virologia , Vírus da Imunodeficiência Símia/classificação , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/patogenicidade , Superinfecção/virologia
11.
J Exp Med ; 192(9): 1317-26, 2000 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-11067880

RESUMO

The effect of infection history is ignored in most animal models of infectious disease. The attachment protein of respiratory syncytial virus (RSV) induces T helper cell type 2-driven pulmonary eosinophilia in mice similar to that seen in the failed infant vaccinations in the 1960s. We show that previous influenza virus infection of mice: (a) protects against weight loss, illness, and lung eosinophilia; (b) attenuates recruitment of inflammatory cells; and (c) reduces cytokine secretion caused by RSV attachment protein without affecting RSV clearance. This protective effect can be transferred via influenza-immune splenocytes to naive mice and is long lived. Previous immunity to lung infection clearly plays an important and underestimated role in subsequent vaccination and infection. The data have important implications for the timing of vaccinations in certain patient groups, and may contribute to variability in disease susceptibility observed in humans.


Assuntos
Pulmão/imunologia , Pulmão/virologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/fisiologia , Animais , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Transplante de Células , Citocinas/metabolismo , Citotoxicidade Imunológica/imunologia , Modelos Animais de Doenças , Suscetibilidade a Doenças/imunologia , Eosinofilia/complicações , Eosinofilia/imunologia , Eosinofilia/patologia , Eosinofilia/virologia , Feminino , Proteína HN/imunologia , Histocitoquímica , Pulmão/patologia , Pulmão/fisiopatologia , Camundongos , Camundongos Endogâmicos BALB C , Orthomyxoviridae/imunologia , Orthomyxoviridae/fisiologia , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Infecções por Vírus Respiratório Sincicial/complicações , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Vírus Sincicial Respiratório Humano/patogenicidade , Baço/citologia , Baço/imunologia , Superinfecção/imunologia , Superinfecção/patologia , Superinfecção/fisiopatologia , Superinfecção/virologia , Proteínas do Envelope Viral , Replicação Viral
12.
Dig Surg ; 17(6): 571-577, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11155001

RESUMO

Sepsis continues to account for a second peak in mortality in patients with severe acute pancreatitis. The prevention of these septic complications and subsequent development of multiple organ dysfunction syndrome remains a major focus for investigators, yet despite considerable clinical and experimental work addressing its etiology, septic complications remain high. Several studies have been designed to demonstrate the mechanism of origin of these septic complications with an attempt to define strategies for their prevention to improve patient outcomes. There is clear evidence that the origin of this secondary bacterial infection arises from enteric bacterial translocation secondary to disruption of the gut mucosal barrier during acute pancreatitis. Strategies designed to prevent secondary pancreatic infection include aggressive fluid resuscitation to maximize organ perfusion, early systemic antibiotic treatment or selective gut decontamination, and recently attempts to block mediators of the systemic inflammatory response. This discussion will summarize our present understanding of the etiopathogenesis of secondary bacterial 'superinfection' of necrotizing pancreatitis and how the initiation of enteral feeding early in the course of acute pancreatitis may prove to be an effective means of preventing and/or reversing the breakdown of the gut mucosal defense barrier.


Assuntos
Nutrição Enteral , Pancreatite Necrosante Aguda/terapia , Superinfecção/prevenção & controle , Translocação Bacteriana , Mucosa Gástrica/microbiologia , Mucosa Gástrica/fisiopatologia , Humanos , Pancreatite Necrosante Aguda/microbiologia , Pancreatite Necrosante Aguda/fisiopatologia , Superinfecção/fisiopatologia , Fatores de Tempo
13.
Int J Pediatr Otorhinolaryngol ; 34(1-2): 171-4, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8770686

RESUMO

Aspecific membranous laryngitis is an unusual but very serious complication of viral infections. Here, we report the uncommon finding of infectious mononucleosis characterized by aspecific membranous laryngitis with fever, dysphonia and severe dyspnea in a 12-year-old girl. Endoscopy showed mucopus and sloughed epithelium forming a pseudomembrane covering almost all the supraglottal region and a supraglottal swelling including the epiglottis and arytenoids. The importance of suspecting diphtheria, epiglottitis, viral or bacterial croup and laringo-tracheo-bronchitis and including them in the differential diagnosis is emphasized.


Assuntos
Mononucleose Infecciosa/complicações , Laringite/etiologia , Infecções Estreptocócicas/diagnóstico , Streptococcus pyogenes/isolamento & purificação , Superinfecção/diagnóstico , Antibacterianos/uso terapêutico , Criança , Crupe/etiologia , Diagnóstico Diferencial , Epiglotite/etiologia , Feminino , Humanos , Laringoscopia , Laringe/patologia , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/fisiopatologia , Superinfecção/tratamento farmacológico , Superinfecção/fisiopatologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-7788421

RESUMO

Superinfection of human immunodeficiency virus (HIV)-1-infected rabbits with Treponema pallidum, Mycobacterium avium, herpes simplex, Candida albicans, Mycoplama incognitus, and malignant catarrhal fever virus, as well as irradiation or cortisone treatment, fails to activate production of infectious virus. For up to 6 months after infection of rabbits with HIV-infected cells or free virus, there are neither clinical symptoms nor positive laboratory tests for detection of HIV. However, after superinfection with other agents, HIV sequences may be transiently found in peripheral blood mononuclear cells by polymerase chain reaction (PCR), and multiple antibodies to HIV antigens may be detected by Western blotting. Both the PCR positivity and Western blot reactivity become negative with time after superinfection. Other than delayed healing of the skin lesions produced by T. pallidum and vaccinia in HIV-infected rabbits, there is no evidence of any immune abnormality. After death, gag sequences are detectable in the splenocytes of essentially every HIV-infected rabbit, and the splenocytes of eight of 25 infected rabbits responded by proliferation to HIV peptides. In addition, gag sequences are detectable in rabbits that are injected with lymphoid cells from HIV-infected rabbits. However, after multiple testing of both peripheral blood of living rabbits and organs of rabbits that died or were killed (spleen, brain, lymph nodes, liver, and gastrointestinal tract), no viable virus has ever been convincingly detected by in vitro cultivation with indicator cells. In contrast to some other published reports, these data indicate that HIV-1 infection of rabbits does not provide a model for AIDS pathogenesis therapy or prevention, but it may be useful as a model to study the relative resistance of a small fraction of the human population to development of AIDS after HIV infection.


Assuntos
Vírus Defeituosos/fisiologia , Infecções por HIV/fisiopatologia , HIV-1/fisiologia , Superinfecção/fisiopatologia , Ativação Viral/fisiologia , Animais , Infecções Bacterianas/fisiopatologia , Candidíase/fisiopatologia , Linhagem Celular , Cortisona/farmacologia , DNA Viral/análise , Produtos do Gene gag/análise , Anticorpos Anti-HIV/sangue , Antígenos HIV/imunologia , HIV-1/efeitos dos fármacos , HIV-1/isolamento & purificação , HIV-1/efeitos da radiação , Humanos , Immunoblotting , Leucócitos Mononucleares/fisiologia , Leucócitos Mononucleares/virologia , Masculino , Reação em Cadeia da Polimerase , Coelhos , Viroses/fisiopatologia , Latência Viral
15.
Gastroenterology ; 108(3): 796-802, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7875481

RESUMO

BACKGROUND/AIMS: Polymerase chain reaction (PCR) is very sensitive. The aim of the study was to reevaluate viral replication in hepatitis D virus (HDV) superinfection by PCR. METHODS: HDV and hepatitis B virus (HBV) were detected by PCR in 185 patients. RESULTS: The acute hepatitis group had the highest detection rate of HDV RNA compared with chronic hepatitis, cirrhosis, hepatocellular carcinoma, and remission groups (63 of 64 vs. 35 of 47, 17 of 23, 19 of 30, and 7 of 21) and the highest alanine aminotransferase (ALT) levels (mean, 1741 U/L vs. 266 to 27 U/L; P < 0.05). The detection rate of HBV DNA was the lowest in the acute group (41%) compared with 66%, 70%, 80%, and 57% in the remaining groups (P < 0.02). At the chronic stage, 13%-25% of cases had HDV RNA, and 30%-48% of cases had HBV DNA detected by PCR but not by traditional method. HDV RNA was associated with ALT levels in horizontal and longitudinal analyses. CONCLUSIONS: HDV superinfection may be divided into the following three phases: acute phase, active HDV replication and suppression of HBV with high ALT levels; chronic phase, decreasing HDV and reactivating HBV with moderate ALT levels; and late phase, development of cirrhosis and hepatocellular carcinoma caused by replication of either virus or remission resulting from marked reduction of both viruses.


Assuntos
Hepatite D/fisiopatologia , Reação em Cadeia da Polimerase , Superinfecção/fisiopatologia , Viremia/diagnóstico , Doença Aguda , Adulto , Idoso , Alanina Transaminase/sangue , Antígenos Virais/análise , DNA Viral/análise , Feminino , Seguimentos , Hepatite D/sangue , Hepatite D/imunologia , Vírus Delta da Hepatite/imunologia , Antígenos da Hepatite delta , Humanos , Fígado/patologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , Superinfecção/sangue , Superinfecção/imunologia , Transcrição Gênica
16.
Rev. mex. patol. clín ; 40(2): 54-7, abr.-jun. 1993. tab
Artigo em Espanhol | LILACS | ID: lil-124671

RESUMO

Con objeto de conocer la frecuencia de infección con el virus de la Hepatitis tipo Delta en nuestra población derechohabiebte, se determinó la presencia de anticuerpos a este virus en 1012 personas con cuadros clínicos de hepatitis Viral Aguda ó Crónica, en las que se había encontrado la presencia de infección con el virus de la hepatitis Viral de tipo B, en el laboratorio Clínico del ospital de Infectología del Centro Médico Nacional "La Raza". Los resultados obtenidos mostraron una baja prevalencia de infección con este virus (1.58 por ciento), 16 de 1012 pacientes estudiados, lo que coloca a nuestro país dentro de los considerados como de bajo nivel de endemicidad. La forma clínica más observada fue la de Superinfección que dio lugar a cuadros clínicos que progresaron a Hepatitis Crónica (75.0 por ciento); el antecedente epidemiológico más frecuente fue el de hemotransfusión; en ningún caso se observó evolución a Hepatitis Fulminante. Su presentación clínica indistinguible de otras formas agudas o crónicas de Hepatitis dificultan su diagnóstico clínico.


Assuntos
Humanos , Masculino , Feminino , Vírus Delta da Hepatite/patogenicidade , Hepatite B/diagnóstico , Hepatite B/fisiopatologia , Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , Superinfecção/fisiopatologia , Superinfecção/microbiologia , Testes Sorológicos/instrumentação
17.
Chest ; 100(2): 439-44, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1864118

RESUMO

This study assessed the incidence, etiology, and consequences of ventilator-associated pneumonia in 1,000 consecutive patients admitted in a medical-surgical intensive care unit (ICU). A total of 264 patients were submitted to mechanical ventilation (MV) for more than 48 hours. Fifty-eight (21.9 percent) patients developed a bacterial pneumonia after a mean of 7.9 days (range, 2 to 40 days) of MV. In addition, they were ten superinfections in nine patients, raising the mean incidence to 25.7 percent. Five patients developed secondary bacteremia, and another five had septic shock. Identification of the causative agent of pneumonia was possible in 47 episodes by means of highly specific techniques (telescoping plugged catheter, blood cultures, and/or necropsy). Thirteen (27.6 percent) of these cases were polymicrobial. The predominant pathogens isolated in the first episode of pneumonia were Gram-negative bacilli (62.6 percent), but a high incidence of Staphylococcus aureus infection (23.2 percent) was detected. Gram-negative bacilli represented 66.6 percent of the total organisms isolated in superinfections. The mortality rate in the pneumonia group was 42 percent; this percentage is similar to mortality rate among MV patients without pneumonia (37 percent). We conclude that nosocomial pneumonia is a frequent complication of MV in the medical-surgical ICU. Ventilator-associated pneumonia does not appear to increase fatality in critically ill patients with a high mortality rate (38 percent); however, it significantly prolongs the length of stay in the ICU for survivors.


Assuntos
Infecção Hospitalar/epidemiologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Pneumonia/epidemiologia , Respiração Artificial , Bactérias/isolamento & purificação , Comorbidade , Infecção Hospitalar/etiologia , Infecção Hospitalar/fisiopatologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/epidemiologia , Pneumonia/etiologia , Pneumonia/microbiologia , Pneumonia/fisiopatologia , Prognóstico , Estudos Prospectivos , Respiração Artificial/efeitos adversos , Espanha/epidemiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/fisiopatologia , Superinfecção/epidemiologia , Superinfecção/fisiopatologia , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Fatores de Tempo
18.
Am J Pathol ; 138(5): 1149-64, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1850960

RESUMO

Superinfection of latently human immunodeficiency virus (HIV)-infected rabbits with either Treponema pallidum or Shope fibroma virus (SFV) activates HIV expression. In addition, HIV-infected rabbits demonstrate prolonged cutaneous lesions (chancres) after intracutaneous challenge with T. pallidum, the causative agent of syphilis. Rabbits were infected by intravenous inoculation of 3 x 10(7) human T-cell lymphotrophic virus type III (HTLV-III)/B10 (HIV-1)-infected H9 (human) cells. Five weeks after initial infection, integrated HIV-1-specific DNA sequences were detected in the DNA of the peripheral blood lymphocytes of only one of eight rabbits using polymerase chain reactions (PCR); human DNA could not be detected at this time. Furthermore HIV infection could not be demonstrated by either seroconversion or PCR during the next 6 months. All HIV-infected rabbits remained clinically healthy and had normal white blood cell counts. Six months after HIV infection, four HIV-infected and two noninfected controls were superinfected with 10(6) T. pallidum in eight skin sites in the shaved skin of the back, and four infected and two control animals were challenged with an intradermal injection with SFV. After infection with either syphilis or SFV, the DNA from the white blood cells of all eight HIV-infected rabbits contained HIV sequences, and HIV sequences were demonstrated in dermal mononuclear cells of the syphilitic lesions by in situ hybridization. The SFV-induced tumors were rejected normally in the HIV-infected rabbits, but four of the four rabbits challenged with T. pallidum had delayed development of cutaneous lesions and three of four demonstrated larger and more prolonged lesions. White blood counts, mitogen responses, and interleukin-2 production remained within normal limits, and seroconversion for HIV was not detected. Three of four rabbits in a second group, challenged with T. pallidum 4 months after HIV-inoculation, also had delayed healing of syphilitic lesions. These results indicate that latent HIV-infection of rabbits may be activated by immunostimulation and that latently HIV-infected rabbits have impaired delayed hypersensitivity reactions. It is hypothesized that true latent HIV-infection in the rabbits is in monocytes and postulated that further immunostimulation may produce infection of lymphocytes and activation of disease.


Assuntos
Vírus do Fibroma dos Coelhos/fisiologia , HIV-1/fisiologia , Superinfecção/fisiopatologia , Sífilis/fisiopatologia , Treponema pallidum/fisiologia , Animais , Antígenos Virais/fisiologia , Sequência de Bases , Biópsia , Southern Blotting , Diferenciação Celular/fisiologia , Concanavalina A/farmacologia , DNA Viral/análise , DNA Viral/genética , Vírus do Fibroma dos Coelhos/imunologia , Vírus do Fibroma dos Coelhos/isolamento & purificação , Infecções por HIV/microbiologia , Infecções por HIV/patologia , Infecções por HIV/fisiopatologia , HIV-1/genética , HIV-1/isolamento & purificação , Linfócitos/microbiologia , Linfócitos/fisiologia , Masculino , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Coelhos , Superinfecção/metabolismo , Superinfecção/patologia , Sífilis/metabolismo , Sífilis/patologia , Treponema pallidum/imunologia , Treponema pallidum/isolamento & purificação
19.
J Hepatol ; 10(1): 41-5, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2307829

RESUMO

A clinicopathologic study in a total of 164 patients with acute hepatitis delta virus (HDV) infection showed that nine male patients (5.5%) had evidence of liver cirrhosis prior to or during the episode of acute hepatitis. All nine patients had typical clinical presentations and laboratory findings of acute viral hepatitis. Four of them had prolonged prothrombin time, three developed ascites and one finally died of hepatic failure. Clinical ascites occurred more frequently in cirrhotic patients with severe but non-fulminant hepatitis than their non-cirrhotic counterparts (p less than 0.05). In addition, histologic studies in five patients with cirrhosis disclosed diffuse lobular necrotizing inflammatory activity, with four showing bridging hepatic necrosis, which also occurs more frequently in cirrhotic than in non-cirrhotic patients (p less than 0.05). The data suggest that HBsAg positive patients with cirrhosis are susceptible to acute HDV infection which may lead to extensive necrosis or even decompensation and failure, simulating decompensation of the underlying liver disease. Therefore, careful clinicopathologic work-ups are required for accurate diagnosis and correct assessment of their outcomes.


Assuntos
Hepatite D/complicações , Cirrose Hepática/complicações , Superinfecção/complicações , Doença Aguda , Adulto , Biópsia , Feminino , Hepatite D/patologia , Hepatite D/fisiopatologia , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Necrose , Superinfecção/patologia , Superinfecção/fisiopatologia
20.
Ann Fr Anesth Reanim ; 9(3): 269-74, 1990.
Artigo em Francês | MEDLINE | ID: mdl-2372153

RESUMO

The treatment of synergistic bacterial soft tissue infections includes usually surgical debridements and radical excisions of necrotic tissues, antibiotic therapy and volumic resuscitation. Hyperbaric oxygen therapy did not prove efficient in these plurimicrobial infections. Their severity is due to virulence synergy of aerobic and anaerobic micro organisms in the involved areas. Sixty patients were admitted in the Surgical Intensive Care Unit (december 1980-march 1989) for severe synergistic soft tissue infections. From 1980 to the end of 1983 the initial surgical treatment was extensive with wide excisions. The antibiotic therapy was selected primarily against anaerobes and gram negative rods. Since 1984 antibiotic therapy was changed to take into account all the micro-organisms found in the initial cultures, especially encountered streptococci species (43 times/60 patients). Initial surgery, after fluid resuscitation and antibiotic therapy, included debridements, colostomy in case of perineal lesion and excisions limited to the really necrotic areas. Under antibiotic therapy according to the bacteriological results, surgical management was performed daily during the first week, later when required. In these series, 14 patients died (23.3%). The mortality during the first period (1980-1983) was high: 7/2 (31.8%) and decreased to 7/38 (18.4%) in the second period (1984-1989). Cellulitis is potentially a highly lethal infection. Early recognition as well as adequate medical and surgical management may be lifesaving.


Assuntos
Infecções Bacterianas/microbiologia , Doenças do Tecido Conjuntivo/etiologia , Infecções Bacterianas/fisiopatologia , Infecções Bacterianas/terapia , Celulite (Flegmão)/microbiologia , Doenças do Tecido Conjuntivo/fisiopatologia , Doenças do Tecido Conjuntivo/terapia , Fasciite/microbiologia , Gangrena/microbiologia , Humanos , Necrose , Superinfecção/microbiologia , Superinfecção/fisiopatologia , Superinfecção/terapia
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