Etiological agents of diarrhea in patients infected by the human immunodeficiency virus-1: a review

Despite the importance of understanding the epidemiology of agents responsible for infectious diarrhea in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) population, the number of articles about this subject is relatively few. The current article summarizes published data on bacterial, fungal, viral and parasitic enteropathogens in the HIV/AIDS seropositive subjects in different countries, regions and localities. In general, there is a great difference in the frequencies of etiological agents due to factors which include immune status, geographical location, climate and socioeconomic conditions. It is important to stress that a great prevalence of infection by emergent agents has been reported in the more advanced stages of AIDS. Therefore, to establish specific treatment depends directly on knowledge of these agents and risk factors associated to their distribution. Moreover, the colonization by potential pathogenic agents verified in these individuals is high thus implicating that they act as carriers. Finally, public health measures of control and prevention must take into consideration the regional previously identified enteropathogens, especially in areas where HIV prevalence is high.

Demographic and Clinical Characteristics of Human Immunodeficiency Virus-Infected Patients Receiving Dialysis in Portugal: a Nationwide Multicentre Survey

Background: Data on human immunodeficiency virus (HIV) infected patients receiving dialysis in Portugal is scarce. Methods: This nationwide epidemiological survey retrospectively evaluates HIV-infected patients on chronic dialysis in Portugal between 1997 and 2002. Results: Sixty-six patients were evaluated (mean age: 39.1±1.6 years, 47 men, 35 black African). Sixty-two patients started dialysis and 4 patients who were receiving dialysis had HIV seroconversion. Eighty-five percent of patients were treated in Lisbon. The annual incidence of HIV-infected patients on chronic dialysis was 0.5% in 1997 and 0.9% in 2002. Seventy-eight percent of patients were HIV-1 infected , 13% had hepatitis B and 31% hepatitis C. Sexual contact was the mode of transmission of HIV in 53% of cases. Four patients had biopsy-proved HIV-associated nephropathy. Ninety-five percent of patients were on chronic hemodialysis. Fifty percent of patients had acquired immunodeficiency syndrome. At follow-up, 12 patients died. HIV-infected CKD patient survival after starting dialysis was 80% at 3 years. Conclusion: The incidence of HIV-infected patients on chronic dialysis in Portugal has almost doubled. Widespread use of highly active antiretroviral therapy and the increasing number of black Africans from former overseas Portuguese colonies now living in Portugal are possible reasons for this large increase.

Epstein Barr virus detection in cervical samples of women living with human immunodeficiency virus

Epstein Barr Virus (EBV) is transmitted commonly by saliva, but it has been found in genital secretions, which suggests sexual transmission and led researchers to connect EBV and cervical neoplasia. People living with human immunodeficiency virus (HIV) are reported to be at high risk of acquiring genital infections and cervical lesions. To verify the presence of EBV in the genital tract and/or it could affect cervical changes, we analyzed cervical smears from 85 HIV seropositive women for EBV DNA determination. EBV was only detected in two (2.3%) samples. The present study provides neither evidence for EBV as sexually transmitted infection nor discards this possibility.

Morphological changes in the digestive system of 93 human immunodeficiency virus positive patients: an autopsy study

Involvement of the digestive system in patients with acquired immunodeficiency syndrome (AIDS) is frequent and many changes in these patients are diagnosed only at autopsy. There are few studies of autopsy with detailed analysis of this system and only one was conducted in Brazil. We evaluated each segment of the digestive system in 93 consecutive autopsies of patients infected with human immunodeficiency virus (HIV) and the importance of these lesions to death. Of these, 90 (96.8%) patients had AIDS. We reviewed medical records, autopsy reports and histological sections from tongue to rectum stained with hematoxylin-eosin. When necessary, we analyzed special stains and immunohistochemistry to investigate infections. There was damage to the digestive system in 73 (78.5%) cases. The most common infections were candidiasis (42%), cytomegalovirus (29%), histoplasmosis (11.8%), toxoplasmosis (9.7%) and mycobacterial infection (9.7%). Malignancies were rare, present in four (4.3%) cases (two Kaposi's sarcoma, one adenocarcinoma and one metastatic embryonal carcinoma). All segments showed lesions: tongue (48.6%), esophagus (44.8%), stomach (44.7%), colon (43.2%) and small intestine (28.9%). The lesions found were immediate cause of death in five (5.4%) cases. In another 36 (38.7%) cases the basic disease was systemic and also compromised the digestive system.

TESTING A SUBTYPE-SPECIFIC GP41 AMPLIFICATION METHOD FOR GENOTYPING INDIVIDUALS INFECTED BY HUMAN IMMUNODEFICIENCY VIRUS TYPE-1 IN THE BRAZILIAN POPULATION OF ITAJAÍ, SOUTH BRAZIL

The method used by YAGYU et al. for the subtype-specific polymerase chain reaction (PCR) amplification of the gp41 transmembrane region of the human immunodeficiency virus type-1 (HIV-1) env gene, was tested. HIV-1 proviral DNA from 100 infected individuals in Itajaí, South Brazil was used to analyze this method. Seventy individuals were determined according to this method as having PCR products at the expected size for subtypes B, C, D and F. Of these individuals, 26 (37.1%) were observed as having the expected amplification for subtype C, and 42 (60%) were observed as having the expected products for subtypes B and D. Of the subtype B and D amplicons, 16 (22.9%) were classified as subtype D, and 26 (37.1%) were classified as subtype B. Two individuals (2.9%) had amplicons that were observed after subtype F-specific amplification was performed. Sequencing and comparing the patient sequences to reference sequences confirmed the classification of sequences of subtypes C and B. However, sequences that were falsely determined as being D and F in the PCR assay were determined as being subtypes C and B, respectively, by sequence analysis. For those individuals from whom no amplified products were obtained, a low viral load that was indicated in their patient history may explain the difficulty in subtyping by PCR methods. This issue was demonstrated by the results of ANOVA when testing the effect of viral load on the success of PCR amplification. The alignment of the obtained sequences with HIV-1 reference sequences demonstrated that there is high intra-subtype diversity. This indicates that the subtype-specific primer binding sites were not conserved or representative of the subtypes that are observed in the Brazilian populations, and that they did not allow the correct classification of HIV-1 subtypes. Therefore, the proposed method by YAGYU et al. is not applicable for the classification of Brazilian HIV-1 subtypes.

Evolution of the Human Immunodeficiency Virus Type 2 Envelope in the First Years of Infection is Associated with the Dynamics of the Neutralizing Antibody Response

Background: Differently from HIV-1, HIV-2 disease progression usually takes decades without antiretroviral therapy and the majority of HIV-2 infected individuals survive as elite controllers with normal CD4+ T cell counts and low or undetectable plasma viral load. Neutralizing antibodies (Nabs) are thought to play a central role in HIV-2 evolution and pathogenesis. However, the dynamic of the Nab response and resulting HIV-2 escape during acute infection and their impact in HIV-2 evolution and disease progression remain largely unknown. Our objective was to characterize the Nab response and the molecular and phenotypic evolution of HIV-2 in association with Nab escape in the first years of infection in two children infected at birth. Results: CD4+ T cells decreased from about 50% to below 30% in both children in the first five years of infection and the infecting R5 viruses were replaced by X4 viruses within the same period. With antiretroviral therapy, viral load in child 1 decreased to undetectable levels and CD4+ T cells recovered to normal levels, which have been sustained at least until the age of 12. In contrast, viral load increased in child 2 and she progressed to AIDS and death at age 9. Beginning in the first year of life, child 1 raised high titers of antibodies that neutralized primary R5 isolates more effectively than X4 isolates, both autologous and heterologous. Child 2 raised a weak X4-specific Nab response that decreased sharply as disease progressed. Rate of evolution, nucleotide and amino acid diversity, and positive selection, were significantly higher in the envelope of child 1 compared to child 2. Rates of R5-to-X4 tropism switch, of V1 and V3 sequence diversification, and of convergence of V3 to a β-hairpin structure were related with rate of escape from the neutralizing antibodies. Conclusion: Our data suggests that the molecular and phenotypic evolution of the human immunodeficiency virus type 2 envelope are related with the dynamics of the neutralizing antibody response providing further support for a model in which Nabs play an important role in HIV-2 pathogenesis.

Parotid enlargement due to adenovirus infection in patient with human immunodeficiency virus infection

The authors report a case of adenovirus- induced enlargement of the parotid gland involving a patient infected with human immunodeficiency virus (HIV). Physical examination revealed good general condition, no fever and bilateral enlargement of the parotid region, which was of increased consistency and slightly tender to palpation. Histological examination of the parotid gland demonstrated a slight periductal lymphomononuclear inflammatory infiltrate with the presence of focal points of necrosis. Tests to determine the presence of fungi and alcohol-acid resistent bacilli were negative. Immunohistochemistry for cytomegalovirus, heipes simplex, HIV p24 antigen and adenovirus showed positivity only for adenovirus in the epithelial nuclei of numerous gland ducts. Tins is the third case of this type reported in the literature, indicating the importance of including adenovirus in the differential diagnosis of this condition.

Cytokine serum levels in patients infected by human immunodeficiency virus with and without Trypanosoma cruzi coinfection

This study assessed the number of CD4 T lymphocytes, the parasitemia and serum levels of interferon gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), interleukin-1 (IL-1), IL-4 and IL-10 of patients infected by human immunodeficiency virus (HIV) and human immunodeficiency virus/Chagas' disease coinfection. CD4 T lymphocytes were low in the two groups of patients, although significantly lower in patients without Chagas' disease. Serum levels of IFN-gamma, IL-4 and TNF-alpha were significantly higher in patients with HIV/Chagas' disease. IL-4/IFN-gamma ratios were higher in patients with HIV/Chagas' disease, which showed a clear balance in favor of Th2-like cytokines in this group of patients. This Th2 balance was higher in patients with detectable parasitemia. We conclude that, although immunosuppression was observed, with CD4 T lymphocytes bellow 200/µm³, these patients did not display reactivation of T. cruzi infection and that a balance favorable to Th2 was associated with the presence of parasitemia.

Vertical transmission of Cryptococcus neoformans from a mother coinfected with human immunodeficiency virus: case report

Disseminated infection with Cryptococcus neoformans was observed in a newborn infant who presented fever and respiratory symptoms since the 52nd day of life. The mother was infected by human immunodeficiency virus and presented pulmonary and meningeal cryptococcal infection. This is a rare case of cryptococcal infection with probable maternal-fetal transmission.

Low prevalence of hepatitis B virus, hepatitis D virus and hepatitis C virus among patients with human immunodeficiency virus or acquired immunodeficiency syndrome in the Brazilian Amazon basin

Comorbidities in human immunodeficiency virus infection are of great interest due to their association with unfavorable outcomes and failure of antiretroviral therapy. This study evaluated the prevalence of coinfection by human immunodeficiency virus and viral hepatitis in an endemic area for hepatitis B in the Western Amazon basin. Serological markers for hepatitis B virus, hepatitis C virus and hepatitis D virus were tested in a consecutive sample of all patients referred for treatment of human immunodeficiency virus or acquired immunodeficiency syndrome. The variables sex, age, origin and exposure category were obtained from medical records and from the sexually transmitted diseases and acquired immunodeficiency syndrome surveillance database. Among 704 subjects, the prevalence of chronic hepatitis B carriage was 6.4% and past infection 40.2%. The presence of hepatitis B was associated with birth in hyperendemic areas of the Amazon basin, male sex and illegal drug use. The overall prevalence of hepatitis C was 5% and was associated with illegal drug use. The prevalence of hepatitis B and C among human immunodeficiency virus or acquired immunodeficiency syndrome patients in the Western Amazon basin was lower than seen elsewhere and is probably associated with the local epidemiology of these viruses and the degree of overlap of their shared risk factors. An opportunity presents itself to evaluate the prevention of hepatitis C through harm reduction policies and hepatitis B through vaccination programs among human immunodeficiency virus or acquired immunodeficiency syndrome patients.

Mother-child transmission of Chagas disease: could coinfection with human immunodeficiency virus increase the risk?

A study was conducted on all newborns from mothers with Chagas disease who were attended at Hospital Donación F. Santojanni between January 1, 2001, and August 31, 2007. Each child was investigated for the presence of Trypanosoma cruzi parasitemia through direct examination of blood under the microscope using the buffy coat method on three occasions during the first six months of life. Serological tests were then performed. Ninety-four children born to mothers infected with Trypanosoma cruzi were attended over the study period. Three of these children were born to mothers coinfected with the human immunodeficiency virus. Vertical transmission of Chagas disease was diagnosed in 13 children, in all cases by identifying parasitemia. The overall Chagas disease transmission rate was 13.8% (13/94). It was 100% (3/3) among the children born to mothers with HIV infection and 10.9% (10/91) among children born to mothers without HIV [Difference = 0.89; CI95 = 0.82-0.95; p = 0.0021]. We concluded that coinfection with HIV could increase the risk of vertical transmission of Chagas disease.

Pre-travel health advice for human immunodeficiency virus-infected travelers, from Rio de Janeiro

Counseling for human immunodeficiency virus infected travelers is becoming increasingly specialized. Previous studies have reported the experience of HIV-infected travelers from temperate-climate countries but little is known about HIV-infected travelers from tropical countries. A retrospective study was conducted on HIV-infected travelers presenting at a travel health clinic in Rio de Janeiro. Eleven journeys by ten people were recorded. Brazil (Amazon region and Northeast) was the destination for six journeys. Other destinations were Peru, Angola, Europe and Asia. Nine attendees were undergoing antiretroviral therapy. Few HIV-infected people from Rio de Janeiro consulted a travel medicine specialist before traveling. Since they travel to destinations in Brazil and abroad where there are endemic diseases not encountered in Rio de Janeiro, careful pre-travel planning needs to be undertaken. Strategies for increasing the frequency of pre-travel consultations need to be developed, such as closer collaboration between HIV clinics and travel health clinics.

Antituberculosis drug-induced hepatotoxicity: a comparison between patients with and without human immunodeficiency virus seropositivity

INTRODUCTION: The prevalence and risk factors for rifampin, isoniazid and pyrazinamide hepatotoxicity were evaluated in HIV-infected subjects and controls. METHODS: Patients with tuberculosis (30 HIV positive and 132 HIV negative), aged between 18 and 80 years-old, admitted to hospital in Brazil, from 2005 to 2007, were selected for this investigation. Three definitions of hepatotoxicity were used: I) a 3-fold increase in the lower limit of normal for alanine-aminotransferase (ALT); II) a 3-fold increase in the upper limit of normal (ULN) for ALT, and III) a 3-fold increase in the ULN for ALT plus a 2-fold increase in the ULN of total bilirubin. RESULTS: In groups with and without HIV infection the frequency of hepatotoxicity I was 77% and 46%, respectively (p < 0.01). Using hepatotoxicity II and III definitions no difference was observed in the occurrence of antituberculosis drug-induced hepatitis. Of the 17 patients with hepatotoxicity by definition III, 3 presented no side effects and treatment was well tolerated. In 8 (36.4%) out of 22, symptoms emerged and treatment was suspended. Alcohol abuse was related to hepatotoxicity only for definition I. CONCLUSIONS: Depending on the definition of drug-induced hepatitis, HIV infection may or may not be associated with hepatotoxicity. The impact that minor alterations in the definition had on the results was impressive. No death was related to drug-induced hepatotoxicity. The emergence of new symptoms after initiating antituberculosis therapy could not be attributed to hepatotoxicity in over one third of the cases.