Ricardo Pereira Igreja

Chagas disease 100 years after its discovery

1340 www.thelancet.com Vol 373 April 18, 2009 Our only stipulation about what to read has been this: that the work be in English and suffi ciently brief to be covered in one or, rarely, several consecutive sessions. Although we meet in a medical centre, we have deliberately not required that the reading have any overt connection to the world of medicine, feeling, as Davis puts it so well, that “the more diffi cult, the more rich, the less immediately relevant a text, the more therapeutic it might be”. After all, what could more touch the heart of medicine than narrative, derived as that word is from the Latin gnoscere (to recognise, examine, study, inspect, get to know, learn, fi nd out). If there has been a downside to our longstanding endeavour, it has been the gradual but unmistakable greying of our participants, most of whom have by now retired from positions within the medical centre or other parts of the university. Still, a fi rst-year medical student has come this year and stayed. Perhaps there is hope...

Diagnosis of meningococcal meningitis in Brazil by use of PCR.

Fever and a petechial rash are strongly associated with meningococcal disease in the city of Rio de Janeiro. Early antibiotic therapy is indicated and, consequently, a reduction of confirmed cases by culture, Gram stain, and latex agglutination test is expected. We evaluated a multiplex PCR assay to identify Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae in biological samples from cases of non-culture proven meningitis with a petechial rash at presentation. To detect DNA in cerebrospinal fluid (n=71) or blood (n=5), a PCR screen was performed, based on the crgA, ply and bexA targets, respectively. Of the total, 70 CSF and 3 blood samples (96%) were positive by PCR for the presence of N. meningitidis DNA. Another PCR assay predicted in 82% of these samples N. meningitidis serogroups A (2%), B (60%), C (7%), X (3%), Y (2%), 29E (2%) or W135 (24%). In non-culture proven meningitis, PCR was found to be a valuable adjunct for the demonstration of meningococcal aetiology.

The utility of the polymerase chain reaction assay for aetiologic definition of unspecified bacterial meningitis cases

Most patients with acute suppurative meningitis are otherwise healthy individuals with regard to immune mechanisms against invasive bacterial disease. This medical emergency is among the most dramatic and potentially ravaging diseases that affect humans, particularly young children. The illness often strikes suddenly, and can either result in death or leave the survivors with significant neurological dysfunctions. The demonstration of a bacterial aetiology is necessary for decisions regarding treatment and prophylaxis. Conventional bacteriological methods frequently fail to identify an agent, as a result of administration of antibiotics or delayed lumbar punctures. We investigated the major aetiologic sources of unspecified bacterial meningitis cases (G00.9, ISCD-10) by polymerase chain reaction (PCR)-based identification of Neisseria meningitidis (crgA), Streptococcus pneumoniae (ply) and Haemophilus influenzae (bexA) in cerebrospinal fluid samples. The multiplex PCR detected N. meningitidis in 92%, S. pneumoniae in 4% and H. influenzae in 1% of the 192 clinical samples assayed; 3% were negative for all three DNA targets. Bacterial DNA detection was found to be a valuable adjunct to enhance bacterial meningitis surveillance when the yield of specimens by culture is reduced. The implementation of PCR assays as a diagnostic procedure in Public Health Laboratories is perceived to be a significant advance in the investigation of bacterial meningitis.

Fasciolíase: relato de dois casos em área rural do Rio de Janeiro

We describe two cases of fascioliasis from rural areas of Rio de Janeiro that are endemic for schistosomiasis, both of which were found during a coprological survey. The patient from Paracambi complained of dizziness. The patient from Sumidouro complained of dizziness, tiredness and cough. She was treated with praziquantel and her stool parasitological examination became negative.

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.

Infectious Diseases Associated with Caves

In recent times, caving has become increasingly popular, with almost 2 million people visiting national park caves each year in the United States. Although the 2 million tourist visits are extremely low risk, smaller numbers of sport cavers are at risk for some high risk conditions, and expedition cavers are at risk for some obscure infections. Infectious diseases like histoplasmosis, rabies, leptospirosis, and tick-borne relapsing fever may be transmitted by the underground fauna. To reduce the risk of illness or injury while caving, knowledge of potential risks before engaging in this activity is important. Caving preparation needs to be carefully planned and executed, including vaccinations, prophylactic medications, and advice regarding safe conduct and behaviors.

Travel medicine and HIV infection

Summary: The number of HIV-infected persons who travel is increasing. This increase arises from those who have benefited from advances in antiretroviral therapy. The key to successful travel is careful pre-trip planning although many patients do not obtain advice before travelling. Travel advice for HIV patients is becoming increasingly specialized, and includes travel vaccination and highly active antiretroviral therapy-related issues. A closer collaboration between HIV and travel health clinics could provide better care for HIV-infected individuals.

Intestinal parasite infections in a rural community of Rio de Janeiro (Brazil): Prevalence and genetic diversity of Blastocystis subtypes

Background Intestinal parasitic infections are considered a serious public health problem and widely distributed worldwide, mainly in urban and rural environments of tropical and subtropical countries. Globally, soil-transmitted helminths and protozoa are the most common intestinal parasites. Blastocystis sp. is a highly prevalent suspected pathogenic protozoan, and considered an unusual protist due to its significant genetic diversity and host plasticity. Methodology/main findings A total of 294 stool samples were collected from inhabitants of three rural valleys in Rio de Janeiro, Brazil. The stool samples were evaluated by parasitological methods, fecal culture, nested PCR and PCR/Sequencing. Overall prevalence by parasitological analyses was 64.3% (189 out of 294 cases). Blastocystis sp. (55.8%) was the most prevalent, followed by Endolimax nana (18.7%), Entamoeba histolytica complex (7.1%), hookworm infection (7.1%), Entomoeba coli (5.8%), Giardia intestinalis (4.1%), Iodamoeba butchilii (1.0%), Trichuris trichiura (1.0%), Pentatrichomonas hominis (0.7%), Enterobius vermicularis (0.7%), Ascaris lumbricoides (0.7%) and Strongyloides stercoralis (0.7%). Prevalence of IPIs was significantly different by gender. Phylogenetic analysis of Blastocystis sp. and BLAST search revealed five different subtypes: ST3 (34.0%), ST1 (27.0%), ST2 (27.0%), ST4 (3.5%), ST8 (7.0%) and a non-identified subtype. Conclusions/significance Our findings demonstrate that intestinal parasite infection rates in rural areas of the Sumidouro municipality of Rio de Janeiro, Brazil are still high and remain a challenge to public health. Moreover, our data reveals significant genetic heterogeneity of Blastocystis sp. subtypes and a possible novel subtype, whose confirmation will require additional data. Our study contributes to the understanding of potential routes of transmission, epidemiology, and genetic diversity of Blastocystis sp. in rural areas both at a regional and global scale.

Voice disorders in residual paracoccidioidomycosis in upper airways and digestive tract

BACKGROUND Paracoccidioidomycosis (PCM) is a systemic mycosis of acute and chronic evolution, caused by species belonging to the genus Paracoccidioides. It is considered the most prevalent systemic endemic mycosis in Latin America, with cases in the tropical and subtropical regions. Residual PCM refers to the fibrotic scar sequelae resulting from the disease treatment which, when associated with collagen accumulation, leads to functional and anatomic alterations in the organs. AIMS The aim of this study was to evaluate the vocal function of patients with residual PCM in upper airways and digestive tract. METHODS We performed a cross-sectional study in 2010 in a cohort of 21 patients with residual PCM in upper airways and digestive tract. RESULTS The average age was 49.48±9.1 years, and only two (9.5%) patients were female. The study was performed in the 1-113 month-period (median 27) after the end of drug treatment. Five (23.8%) patients had alterations in the larynx as a sequela of the disease. However, all patients had vocal changes in vocal auditory perceptual analysis by GRBASI scale. The computerized acoustic analysis using the software Vox Metria, showed that 11 patients (52.4%) presented alterations in jitter, 15 (71.4%) in shimmer, 8 (38.1%) in F0, 4 (19%) in glottal to noise excitation (GNE), 7 (33.3%) in the presence of noise and 12 (57.1%) in the presence of vibratory irregularity. CONCLUSIONS The great frequency of alterations in residual PCM suggests that the patients in such phase could benefit from a multidisciplinary treatment, offering them integral monitoring of the disease, including speech rehabilitation after the PCM is healed.

Infectious Diseases and Extreme Sports

Adventure travel has led to an increasing risk for contact with pathogens uncommon in industrialized countries. Extreme sport athletes may be at increased risk because they often travel through poorer, rural areas of tropical and subtropical regions to reach their destinations. In addition, competitions can take place in extreme locations like jungles, mountains, or deserts. Infection with unusual organisms may occur through exposures to lakes, rivers, caves, and canyons, as well as insect vectors. Outbreaks of infections have been associated with caving, canoeing, kayaking, rafting, triathlons, and multisport races. Diseases like malaria, leptospirosis, myiasis, schistosomiasis, tickborne rickettsial diseases, and rabies occurred or are a potential hazard for extreme sport athletes. The lack of immediate medical care can complicate and worsen the severity of these diseases. Physicians caring for extreme sport competitors must take a careful travel and exposure history and have a high index of suspicion for unusual diseases. To reduce the risk of illness or injury, knowledge of potential risks before engaging in this activity is important. Extreme sport preparation needs to be carefully planned and executed, including vaccinations, prophylactic medications, and advice regarding safe conduct and behaviors.