CHEMOPROPHYLAXIS TO CONTROL LEPROSY AND THE PERSPECTIVE OF ITS IMPLEMENTATION IN BRAZIL: A PRIMER FOR NON-EPIDEMIOLOGISTS

The occurrence of leprosy has decreased in the world but the perspective of its elimination has been questioned. A proposed control measure is the use of post-exposure chemoprophylaxis (PEP) among contacts, but there are still questions about its operational aspects. In this text we discuss the evidence available in literature, explain some concepts in epidemiology commonly used in the research on this topic, analyze the appropriateness of implementing PEP in the context of Brazil, and answer a set of key questions. We argue some points: (1) the number of contacts that need to receive PEP in order to prevent one additional case of disease is not easy to be generalized from the studies; (2) areas covered by the family health program are the priority settings where PEP could be implemented; (3) there is no need for a second dose; (4) risk for drug resistance seems to be very small; (5) the usefulness of a serological test to identify a higher risk group of individuals among contacts is questionable. Given that, we recommend that, if it is decided to start PEP in Brazil, it should start on a small scale and, as new evidence can be generated in terms of feasibility, sustainability and impact, it could move up a scale, or not, for a wider intervention.

HEPATOCELLULAR CARCINOMA IN A NON-CIRRHOTIC PATIENT WITH SUSTAINED VIROLOGICAL RESPONSE AFTER HEPATITIS C TREATMENT

Chronic infection by hepatitis C virus (HCV) is one of the main risk factors for the development of liver cirrhosis and hepatocellular carcinoma. However, the emergence of hepatocellular carcinoma (HCC) in non-cirrhotic HCV patients, especially after sustained virological response (SVR) is an unusual event. Recently, it has been suggested that HCV genotype 3 may have a particular oncogenic mechanism, but the factors involved in these cases as well as the profile of these patients are still not fully understood. Thus, we present the case of a non-cirrhotic fifty-year-old male with HCV infection, genotype 3a, who developed HCC two years after treatment with pegylated-interferon and ribavirin, with SVR, in Brazil.

Evolutive pattern of schistosomiasis and life-span of S. mansoni in patients living in non-endemic area in Brazil

Out of 2484 patients harboring S. mansoni seen in Rio de Janeiro, 1197 had been living permanently out of endemic area frorn one to 30 years, without any possibility of reinfection; 90.1% of these 1197 patients were first seen with, hepato-intestinal schistosomiasis and only 9.9% with hepatosplenic form. 55% of thern still had S. mansoni active infection 6 years or more after they had left the endemic area and 26.5% remained infected for more than 10 years. The patients with intestinal or hepato-intestinal schistosomiasis did not develop the most severe form whether they had been treated or not, and the hepatosplenic patients had a long time to deteriorate.

Effects of lethal and non-lethal malaria on the mononuclear phagocyte system

The effects ofone non-lethal species ofmalarialparasite, Plasmodium yoelii, and one lethal species, P. berghei, on the mononuclear phagocyte system (MPS) of BALB/c mice were studied. P. yoelii caused a greater and more sustained expansion and activation of the MPS, and the two major populations of spleen phagocytic cells-red pulp and marginal zone macrophages - exhibited a greater increase in numbers in this infection. During the course of P. berghei mataria, the spleen was progressively occupied by haematopoietic tissue and, at the terminal stage of infection, an extensive depletion of lymphocytes and macrophages was apparent. The possibility was suggested that the outcome of mataria may be inftuenced by the particular way the parasite interacts with the MPS.

Low frequency of side effects following an incidental 25 times concentrated dose of yellow fever vaccine

In August/1999, a group of 14 adults from the staff of a private hospital in Contagem -- Minas Gerais State, Brazil, received unintentionally a 25 times concentrated dose of the 17-DD yellow fever vaccine (Bio-Manguinhos), due to a mistake at the reconstitution step. All patients were clinically and laboratorially evaluated at days 5, 13 and 35 post vaccination. Frequency of side effects and clinical observations of this group of individuals were not different from the observed in recipients immunized with normal doses of the vaccine. At the second and third evaluation none of the subjects reported symptoms. None of the patients presented abnormalities at the physical examination at none of the time points and in all cases the blood examination was normal, except for a reduced number of platelets that was detected in one subject at the first and second evaluation and reverted to normal at third evaluation. At the first evaluation point, 8 subjects were serum negative and 6 serum positive for yellow fever at the plaque reduction neutralization test. In 5 subjects the observed titre was 10 times higher as the baseline of 2.36 Log10 mUI/ml. The samples collected at second and third evaluation (13th and 35th days) demonstrated that all subjects responded to the vaccination with the exception of one that did not present a positive result in any of the samples collected. This evaluation confirms the safety of the 17-DD yellow fever vaccine.

Malaria outbreaks in a non-endemic area of Brazil, 2005

In March 2005, a resident of the municipality of Monte Alegre de Minas, State of Minas Gerais, without any history of traveling to endemic areas for malaria, was diagnosed with Plasmodium vivax infection and local mosquito-borne transmission was suspected. The epidemiological investigation identified another 10 cases with local transmission and all of them were related to the imported malaria case that was detected in this region. The potential exposure site was the banks of the river Tejuco, an area frequented by mineral prospectors. Some of these prospectors were known to have come from states with malaria transmission. In the autochthonous cases, Plasmodium vivax and Plasmodium falciparum were diagnosed. Entomological investigation identified Anopheles (Nyssorhynchus) darlingi, Anopheles (Nyssorhynchus) albitarsis, Anopheles (Nyssorhynchus) triannulatus and Anopheles (Nyssorhynchus) parvus. After the first outbreak, another three autochthonous cases were notified in municipality of Monte Alegre de Minas, in the same year. The occurrence of these outbreaks highlights the importance of surveillance systems in areas that are nonendemic for malaria.

Acquired non-Chagas megacolon associated with the use of psychiatric medication: case report and differential diagnosis with Chagas megacolon

A case of acquired megacolon in a 62-year-old man with acute abdomen due to sigmoid volvulus is reported. The case was associated with the use of psychiatric medications. The aim in this report was to emphasize the differential diagnosis with Chagas megacolon. Anatomopathological examination did not show any evidence of denervation, ganglionitis and/or myositis, and the serological test for Chagas disease was negative.

Diphyllobothrium latum infection in a non-endemic country: case report

Diphyllobothriasis, which is rarely described in Brazil, was reported initially as a travelers’ disease and as an accidental infection in individuals who ate raw freshwater fish. This report aims to present the case of a 20-year-old patient with confirmed Diphyllobothrium latum infection.

Prevalence and clinical outcomes of episodes of ventilator-associated pneumonia caused by SPM-1-producing and non-producing imipenem-resistant Pseudomonas aeruginosa

INTRODUCTION: Pseudomonas aeruginosa is a leading cause of ventilator-associated pneumonia (VAP) and exhibits high rates of resistance to several antimicrobial drugs. The carbapenens are usually the drugs of choice against this microorganism. However, the carbapenem resistance has increased among these strains worldwide. The presence of metallo-β-lactamases (MBL) has been pointed out as a major mechanism of resistance among these strains. No previous study addressed outcomes of respiratory infections caused by these strains. METHODS: Our group sought to analyze the epidemiology and clinical outcomes of patients with VAP caused by imipenem-resistant P. aeruginosa. A total of 29 clinical isolates of carbapenem-resistant Pseudomonas aeruginosa were screened for metallo-β-lactamase (MBL) genes. RESULTS: Demographic and clinical variables were similar between the SPM-1-producing and non-SPM-1-producing group. Five (17.2%) isolates were positive for blaSPM-1. No other MBL gene was found. All patients were treated with polymyxin B. The infection-related mortality was 40% and 54.2% for SPM-1-producing and -non-producing isolates, respectively. CONCLUSIONS: There were no differences in epidemiological and clinical outcomes between the two groups.

Molecular characterization of rabies virus isolated from non-haematophagous bats in Brazil

INTRODUCTION: Rabies is an important zoonosis that causes thousands of deaths worldwide each year. Although the terrestrial cycle, mainly transmitted by dogs, is controlled in Brazil, the aerial cycle remains a serious public health issue, besides the economic problem. In the aerial cycle, the haematophagous bat Desmodus rotundus is the main source of infection, where several different species of non-haematophagous bats can be infected and can transmit the virus. METHODS: The aim of this work was to study the epidemiological pattern of rabies using antigenic characterization with monoclonal antibodies and genetic characterization by reverse-transcriptase polymerase chain reaction followed by sequencing and phylogenetic analysis of non-haematophagous bats' and herbivorous animals' central nervous system samples from the western region of the State of São Paulo, Brazil. RESULTS: From 27 samples, 3 antigenic variants were identified: AgV-3, AgV-4, and AgV-6; and from 29 samples, 5 different clusters were identified, all belonging to the rabies virus species. CONCLUSIONS: Although only non-haematophagous bats were evaluated in the studied region, the majority of samples were from antigenic and genetic variants related to haematophagous bats Desmodus rotundus. Samples from the same antigenic variant were segregated in more than one genetic cluster. This study demonstrated the diversity of rabies virus genetic lineages presented and circulating in non-haematophagous bats in the studied region.

Detection of Dientamoeba fragilis in patients with HIV/AIDS by using a simplified iron hematoxylin technique

INTRODUCTION: Studies strongly indicate Dientamoeba fragilis as one of the causes of diarrhea in human immunodeficiency virus (HIV) patients. METHODS: The objective of the present study was to evaluate the prevalence of D. fragilis associated with the causes of diarrhea in 82 HIV/ AIDS patients hospitalized at the Instituto de Infectologia Emílio Ribas from September 2006 to November 2008. RESULTS: In total, 105 samples were collected from 82 patients. Unprotected sex was the most frequent cause of HIV infection (46.3%), followed by the use of injectable or non-injectable drugs (14.6%). Patients presented with viral loads of 49-750,000 copies/ mL (average: 73,849 ± 124,850 copies/mL) and CD4 counts ranging of 2-1,306 cells/mm³ (average: 159 ± 250 cells/mm³). On an average, the odds of obtaining a positive result by using the other techniques (Hoffman, Pons and Janer or Lutz; Ritchie) were 2.7 times higher than the chance of obtaining a positive result by using the simplified iron hematoxylin method. Significant differences were found between the methods (p = 0.003). CONCLUSIONS: The other techniques can detect a significantly greater amount of parasites than the simplified iron hematoxylin method, especially with respect to Isospora belli, Cryptosporidium sp., Schistosoma mansoni, and Strongyloides stercoralis, which were not detected using hematoxylin. Endolimax nana and D. fragilis were detected more frequently on using hematoxylin, and the only parasite not found by the other methods was D. fragilis.

Circulation of the rabies virus in non-hematophagous bats in the city of Rio de Janeiro, Brazil, during 2001-2010

INTRODUCTION: Rabies is one of the most known lethal zoonosis, responsible for 55,000 human deaths per year. It is transmitted to humans mainly by the bite of domestic or wild animals infected with the virus. This paper shows the circulation of this virus in non-hematophagous bats in the City of Rio de Janeiro, Brazil. METHODS: A survey was performed on the number of bats that had been sent for diagnosis by the Seção de Virologia of the Instituto Municipal de Medicina Veterinária Jorge Vaitsman and were positive for rabies. The positive animals were identified, and the isolated viruses were sent for antigenic typification with indirect immunofluorescence. The results were compared with the antigenic panel of the Centers for Disease Control and Prevention. RESULTS: During 2001-2010, the laboratory received 555 non-hematophagous bats for rabies diagnosis, with 198 (35.7%) from Rio de Janeiro City. A total of 11 (5.5%) animals were positive for this disease. Antigenic typification revealed the predominance of variant 3 in 9 (81.8%) of the isolated viruses; 1 virus was classified as variant 4 and 1 variant was identified that segregated with the viruses in insectivorous bats. CONCLUSIONS: The data obtained in this study showed the presence of the rabies virus in synanthropic populations of non-hematophagous bats in the City of Rio de Janeiro. The circulation of this agent in these animals represents a serious risk to human and animal health and requires attention and control measures by the authorities.

Methicillin-resistant Staphylococcus aureus bloodstream infection: risk factors and clinical outcome in non-intensive-care units

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is spread out in hospitals across different regions of the world and is regarded as the major agent of nosocomial infections, causing infections such as skin and soft tissue pneumonia and sepsis. The aim of this study was to identify risk factors for methicillin-resistance in Staphylococcus aureus bloodstream infection (BSI) and the predictive factors for death. METHODS: A retrospective cohort of fifty-one patients presenting bacteraemia due to S. aureus between September 2006 and September 2008 was analysed. Staphylococcu aureus samples were obtained from blood cultures performed by clinical hospital microbiology laboratory from the Uberlândia Federal University. Methicillinresistance was determined by growth on oxacillin screen agar and antimicrobial susceptibility by means of the disk diffusion method. RESULTS: We found similar numbers of MRSA (56.8%) and methicillin-susceptible Staphylococcus aureus (MSSA) (43.2%) infections, and the overall hospital mortality ratio was 47%, predominantly in MRSA group (70.8% vs. 29.2%) (p=0.05). Age (p=0.02) was significantly higher in MRSA patients as also was the use of central venous catheter (p=0.02). The use of two or more antimicrobial agents (p=0.03) and the length of hospital stay prior to bacteraemia superior to seven days (p=0.006) were associated with mortality. High odds ratio value was observed in cardiopathy as comorbidity. CONCLUSIONS: Despite several risk factors associated with MRSA and MSSA infection, the use of two or more antimicrobial agents was the unique independent variable associated with mortality.

Echocardiographic parameters associated with pulmonary congestion in outpatients with Chagas' cardiomyopathy and non-chagasic cardiomyopathy

INTRODUCTION: Despite significant left ventricular (LV) systolic dysfunction and cardiomegaly, pulmonary congestion does not seem to be a major finding in Chagas' cardiomyopathy (CC). This study sought to identify echocardiographic parameters associated with pulmonary congestion in CC and in dilated cardiomyopathy of other etiologies, such as non-CC (NCC), and to compare pulmonary venous hypertension between the two entities. METHODS: A total of 130 consecutive patients with CC and NCC, with similar echocardiographic characteristics, were assessed using Doppler echocardiography and chest radiography. Pulmonary venous vessel abnormalities were graded using a previously described pulmonary congestion score, and this score was compared with Doppler echocardiographic parameters. RESULTS: NCC patients were older than CC patients (62.4 ± 13.5 × 47.8 ± 11.2, p = 0.00), and there were more male subjects in the CC group (66.2% × 58.5%, p = 0.4). Pulmonary venous hypertension was present in 41 patients in the CC group (63.1%) and in 63 (96.9%) in the NCC group (p = 0.0), the mean lung congestion score being 3.2 ± 2.3 and 5.9 ± 2.6 (p = 0.0), respectively. On linear regression multivariate analysis, the E/e' ratio (β = 0.13; p = 0.0), LV diastolic diameter (β = 0.06; p = 0.06), left atrial diameter (β = 0.51; p = 0.08), and right ventricular (RV) end-diastolic diameter (β = 0.02; p = 0.48) were the variables that correlated with pulmonary congestion in both groups. CONCLUSIONS: Pulmonary congestion was less significant in patients with CC. The degree of LV of systolic and diastolic dysfunction and the RV diameter correlated with pulmonary congestion in both groups. The E/e' ratio was the hallmark of pulmonary congestion in both groups.