Radiographic features of pulmonary tuberculosis in patients infected by HIV: is there an objective indicator of co-infection?

This study aimed to compare the radiographic characteristics of patients with pulmonary tuberculosis (TB) and human immunodeficiency virus (HIV) infection with those of HIV-negative patients. In all, 275 TB patients attending the outpatients clinics at the University Hospital/UFPE, were studied from January 1997 to March 1999. Thirty nine (14.2%) of them were HIV+, with a higher frequency of males in this group (p=0.044). Seventy-five percent of the HIV+ patients and 19% of the HIV- had a negative tuberculin test (PPD) (p < 0.001). The proportion of positive sputum smears in the two groups was similar. The radiological finding most strongly associated with co-infection was absence of cavitation (p < 0.001). It may therefore be concluded that the lack of cavitation in patients with pulmonary TB may be considered a useful indicator of the need to investigate HIV infection. This approach could contribute to increasing the effectiveness of local health services, by offering appropriate treatment to co-infected patients.

Outbreak of aggressions and transmission of rabies in human beings by vampire bats in northeastern Brazil

Outbreaks of attacks upon human beings by vampire bats seems to be a common phenomenon in several regions of Latin America, but the occurrence of rabies infection among humans bled by vampires, is relatively low. In the present study, two outbreaks of human rabies transmitted by common vampire bats (Desmodus rotundus) are described from Bahia State, Northeasthern Brazil, in 1991 and 1992. The first was recorded in Aporá where 308 people were bled by vampire bats and three of these die from this zoonosis. The 2nd outbreak occurred in Conde where only five people were bled by vampires, and two deaths by rabies were registered. Our data suggest that rabies transmitted by bats basically depends on the presence of virus in the vampire bat population and not on the number of humans bled by them.

New evidence of spontaneous cure in human Chagas' disease

A new case of spontaneous cure of human Chagas' disease is described in Uruguay. An 87-year-old man who had a typical acute phase of Trypanosoma cruzi infection in 1947 and never received specific treatment against the disease, when examined in 1998 revealed several completely negative parasitological and serological tests, including traditional serology, PCR and flow cytometry. As a whole, such findings fulfill the current criteria to define the cure of Chagas' disease. Clinical data suggest the possibility of a benign evolution of Chagas' disease in this case, but the basic findings (slight cardiac and esophageal impairment) could also be due to the advanced age of the patient.

Clinical presentation of parvovirus B19 infection in HIV-infected patients with and without AIDS

Human parvovirus B19 replicates in erythrocyte precursors. Usually, there are no apparent hematological manifestations. However, in individuals with high erythrocyte turnover, as in patients with sickle-cell disease and in the fetus, the infection may lead to severe transient aplasia and hydrops fetalis, respectively. In AIDS patients, persistent infection may result in chronic anemia. By contrast, in HIV-positive patients without AIDS the infection evolves as a mild exanthematous disease. Two clinical descriptions exemplify these forms of presentation. In the first, an AIDS patient presented with bone marrow failure that responded to immunoglobulin. In the second, an HIV-positive patient without AIDS had a morbilliform rash, and needed no treatment. Knowing that an AIDS patient has chronic B19 anemia lessens concern about drug anemia; protects the patient from invasive diagnostic maneuvers; and prevents the patient from disseminating the infection. In AIDS patients with pure red cell aplasia, a search for parvovirus B19 DNA in the serum or in the bone marrow is warranted.

Serological and parasitological study and report of the first case of human babesiosis in Colombia

A study on the presence of Babesia in humans was performed in Puerto Berrío (Latitude 6.50deg. Longitude: -74.38deg. River: Magdalena. Area: 74.410km², Colombia-South America). Indirect immunofluorescence, thin and thick blood smears were used to study 194 individuals. Patients were grouped according to their risk-factors for Babesia infection: (group 1) individuals with fever, chills, sweating and other malaria-type symptoms; (group 2) symptomatic and asymptomatic individuals from local cattle ranches, which were enrolled in an active form, and (group 3) workers from the local slaughterhouse. Seven individuals were serologically positive for Babesia: Three individuals presented IgM antibodies against B. bovis, while one had IgG against this species; one individual had IgM against B. bigemina, another had IgG and a third both IgM and IgG against this species. Only one individual was parasitologically positive for Babesiaand serologically positive for Babesia bovis (IgM 1:64)

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.

Diagnosing human asymptomatic visceral leishmaniasis in an urban area of the State of Minas Gerais, using serological and molecular biology techniques

A population-based cross-sectional study was set up in Sabará country, Southeastern Brazil, to identify asymptomatic human visceral leishmaniasis in an urban area of low disease prevalence. Blood was collected on filter paper (n=1,604 inhabitants) and examined by indirect immunofluorescent test, enzyme-linked immunosorbent assay and immunochromatographic strip test. The prevalence rates of infection ranged from 2.4 to 5.6% depending on the test used. One year later, venous blood was collected in a subset of 226 participants (102 seropositive and 124 seronegative). The tests performed were IFAT, ELISA, rk39-ELISA, polymerase chain reaction and hybridization with Leishmania donovani complex probe. No clinical signs or symptoms of leishmaniasis were observed. Using hybridization as a reference test, the sensitivity and specificity of serology were respectively: 24.8 and 71% (ELISA); 26.3 and 76.3% (rk-39); 30.1 and 63.4% (IFAT). Due to disagreements, different criteria were tested to define the infection and hybridization should be considered in epidemiological studies.

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.

Paracoccidioidomycosis: no genetic damage in human peripheral blood cells of patients assessed by single-cell gel (comet) assay

Paracoccidioidomycosis is a systemic fungal infection caused by Paracoccidioides brasiliensis. As infectious diseases can cause DNA damage, the authors aimed at analyzing DNA breakage in peripheral blood cells of patients with paracoccidioidomycosis by using the comet assay. The results suggested that paracoccidioidomycosis does not cause genotoxicity.

Further evidence of spontaneous cure in human Chagas disease

An acute case of Chagas disease was studied in 1944, with clinical and laboratory follow-up until 2007, in Bambuí, Minas Gerais, Brazil. A five-year-old girl living in a rural hut that was highly infested with Triatoma infestans presented a febrile clinical condition compatible with the acute form of trypanosomiasis. She presented a positive thick blood smear, but never again showed serological and/or parasitological evidence of Trypanosoma cruzi infection, on several occasions. This patient never received any specific treatment and, to this day, she remains completely asymptomatic, with normal findings from clinical, electrocardiographic, X-ray and echocardiographic examinations.

Detection of human herpesvirus-7 by qualitative nested-PCR: comparison between healthy individuals and liver transplant recipients

Diagnosis of human herpesvirus-7 active infection in transplant patients has proved difficult, because this virus is ubiquitous and can cause persistent infections in the host. The significance of viral DNA detected in leukocytes by PCR is unclear and cross-reaction in serological tests may occur. This study aimed to evaluate nested-PCR to detect human herpesvirus-7 active infection in liver transplant recipients compared to healthy individuals. human herpesvirus-7 nested-PCR was performed on leukocytes and sera of 53 healthy volunteers and sera of 29 liver transplant recipients. In healthy volunteers, human herpesvirus-7 was detected in 28.3% of leukocytes and 0% of serum. human herpesvirus-7 was detected in sera of 48.2% of the liver transplant recipients. Nested-PCR on DNA extracted from leukocytes detected latent infection and the study suggests that nested-PCR performed on serum could be useful to detect human herpesvirus-7 active infection in liver transplant recipients.

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.

Human papillomavirus genotypes in asymptomatic young women from public schools in Rio de Janeiro, Brazil

INTRODUCTION: The aim of this work was to survey HPV information from a random population of young women from Rio de Janeiro, Brazil. METHODS: This cross-sectional study included cervical samples from 241 female students. To determine human papillomavirus status, polymerase chain reaction amplification was performed. HPV typing was determined by restriction fragment length polymorphism analysis. Demographic data, life style, sexual and gynecological history were obtained through use of a structured questionnaire. RESULTS: The average age of the women was 19.6 years-old (SD=3.4 years). HPV prevalence was 27.4%. Nineteen different HPV genotypes were detected, including 13 high risk types. HPV 16 was the most prevalent type (6.2%), followed by 31 (4.1 %) and 66 (3.7%). Most of the oncogenic types belonged to the A9 species (28/48). The frequency of women infected by at least one oncogenic type was significantly higher than those only infected by low risk types (18.7% versus 7.5%). Cervical changes were detected in 12.5% of the sample and were significantly linked to infection with HPV types of the A9 species. Demographic variables, sexual initiation, or number of sexual partners were not associated with HPV prevalence, variety of HPV genotypes or oncogenic types. CONCLUSIONS: The relative frequency of HPV genotypes other than vaccine types in young females should be taken into account when evaluating vaccination strategies. Due to the high prevalence of HPV infection among the population studied, implementation of sex education in schools, promotion of condom use and an organized screening program to prevent cervical cancer must be encouraged for this age group.

Evaluation of the use of real-time PCR for human T cell lymphotropic virus 1 and 2 as a confirmatory test in screening for blood donors

INTRODUCTION: HTLV-1/2 screening among blood donors commonly utilizes an enzyme-linked immunosorbent assay (EIA), followed by a confirmatory method such as Western blot (WB) if the EIA is positive. However, this algorithm yields a high rate of inconclusive results, and is expensive. METHODS: Two qualitative real-time PCR assays were developed to detect HTLV-1 and 2, and a total of 318 samples were tested (152 blood donors, 108 asymptomatic carriers, 26 HAM/TSP patients and 30 seronegative individuals). RESULTS: The sensitivity and specificity of PCR in comparison with WB results were 99.4% and 98.5%, respectively. PCR tests were more efficient for identifying the virus type, detecting HTLV-2 infection and defining inconclusive cases. CONCLUSIONS: Because real-time PCR is sensitive and practical and costs much less than WB, this technique can be used as a confirmatory test for HTLV in blood banks, as a replacement for WB.