João Barberino Santos

Effectiveness of ten-valent pneumococcal conjugate vaccine against invasive pneumococcal disease in Brazil: a matched case-control study

BACKGROUND In March 2010, Brazil introduced the ten-valent pneumococcal conjugate vaccine (PCV10), which was licensed based on non-inferiority of immunological correlates of protection compared with the seven-valent vaccine. The schedule comprised three primary doses at ages 2 months, 4 months, and 6 months, and a booster dose at age 12 months. A single catch-up dose was offered for children aged 12-23 months at the time of introduction. We assessed PCV10 effectiveness against invasive pneumococcal disease in Brazilian children. METHODS Invasive pneumococcal disease, defined as isolation of Streptococcus pneumoniae from blood, cerebrospinal fluid, or another normally sterile site, was identified in children age-eligible for at least one PCV10 dose through laboratory-based and hospital-based surveillance in ten states in Brazil from March 1, 2010, until Dec 31, 2012. We aimed to identify four age-matched and neighbourhood-matched controls for each case. We used conditional logistic regression and calculated PCV10 effectiveness as (1-adjusted matched odds ratio) × 100% for vaccine-type and vaccine-related serotypes (ie, in the same serogroup as a vaccine serotype). FINDINGS In 316 cases (median age 13·2 months, range 2·6-53·1) and 1219 controls (13·3 months, 2·6-53·1), the adjusted effectiveness of an age-appropriate PCV10 schedule was 83·8% (95% CI 65·9-92·3) against vaccine serotypes, and 77·9% (41·0-91·7) against vaccine-related serotypes. Serotype-specific effectiveness was shown for the two most common vaccine serotypes-14 (87·7%, 60·8-96·1) and 6B (82·8%, 23·8-96·1)-and serotype 19A (82·2%, 10·7-96·4), a serotype related to vaccine serotype 19F. A single catch-up dose in children aged 12-23 months was effective against vaccine-type disease (68·0%, 17·6-87·6). No significant effectiveness was shown against non-vaccine serotypes for age-appropriate or catch-up schedules. INTERPRETATION In the routine immunisation programme in Brazil, PCV10 prevents invasive disease caused by vaccine serotypes. PCV10 might provide cross-protection against some vaccine-related serotypes. FUNDING Brazilian Ministry of Health, Pan-American Health Organization, and US Centers for Disease Control and Prevention.

Bacterial and fungal colonization of burn wounds

A prospective study of fungal and bacterial flora of burn wounds was carried out from February 2004 to February 2005 at the Burns Unit of Hospital Regional da Asa Norte, Brasília, Brazil. During the period of the study, 203 patients were treated at the Burns Unit. Wound swab cultures were assessed at weekly intervals for four weeks. Three hundred and fifty four sampling procedures (surface swabs) were performed from the burn wounds. The study revealed that bacterial colonization reached 86.6% within the first week. Although the gram-negative organisms, as a group, were more predominant, Staphylococcus aureus (28.4%) was the most prevalent organism in the first week. It was however surpassed by Pseudomonas aeruginosa form third week onwards. For S. aureus and P. aeruginosa vancomycin and polymyxin were found to be the most effective drugs. Most of the isolates showed high level resistance to antimicrobial agents. Fungi were found to colonize the burn wound late during the second week postburn, with a peak incidence during the third and fourth weeks. Species identification of fungi revealed that Candida tropicalis was the most predominant, followed by Candida parapsilosis. It is crucial for every burn institution to determine the specific pattern of burn wound microbial colonization, the time-related changes in the dominant flora, and the antimicrobial sensitivity profiles. This would enable early treatment of imminent septic episodes with proper empirical systemic antibiotics, without waiting for culture results, thus improving the overall infection-related morbidity and mortality.

Thrombocytopenia in malaria: who cares?

Despite not being a criterion for severe malaria, thrombocytopenia is one of the most common complications of both Plasmodium vivax and Plasmodium falciparum malaria. In a systematic review of the literature, platelet counts under 150,000/mm³ ranged from 24-94% in patients with acute malaria and this frequency was not different between the two major species that affected humans. Minor bleeding is mentioned in case reports of patients with P. vivax infection and may be explained by medullary compensation with the release of mega platelets in the peripheral circulation by megakaryocytes, thus maintaining a good primary haemostasis. The speculated mechanisms leading to thrombocytopenia are: coagulation disturbances, splenomegaly, bone marrow alterations, antibody-mediated platelet destruction, oxidative stress and the role of platelets as cofactors in triggering severe malaria. Data from experimental models are presented and, despite not being rare, there is no clear recommendation on the adequate management of this haematological complication. In most cases, a conservative approach is adopted and platelet counts usually revert to normal ranges a few days after efficacious antimalarial treatment. More studies are needed to specifically clarify if thrombocytopenia is the cause or consequence of the clinical disease spectrum.

Thrombocytopenia in patients with dengue virus infection in the Brazilian Amazon

Thrombocytopenia may be occasionally observed in dengue fever (DF) but is a constant feature and one of the diagnostic criteria of dengue hemorrhagic fever (DHF). Its clinical presentation and relevance is still poorly described in the literature. Patients with fever and bleeding were referred to a tertiary care center in Manaus, in the Western Brazilian Amazon during the outbreak of dengue in 2001. They were hospitalized for clinical observation and supportive care. Platelet counts were performed on admission and throughout the hospitalization. Only patients with a serological confirmation or viral isolation of the dengue virus were included. One hundred and seventy eight patients were enrolled in the study (118 with DF and 60 with DHF). There was no association between the presence of active bleeding and the degree of thrombocytopenia on admission (P = 0.302). A positive tourniquet test, hematemesis and ecchymoses were more frequent in DHF patients (P < 0.05). Patients with DHF had lower platelet counts than patients with DF (P < 0.001). There was a positive correlation between platelet counts and plasma albumin levels (r = 0.217; P = 0.016) and a negative correlation with ALT values (r = −0.3; P = 0.001). Clinical manifestations of thrombocytopenia are not related only to the number of peripheral platelets in dengue infection, but its recovery is associated with clinical improvement. The level of platelets correlates with the vascular leakage of proteins and liver damage.

Predictive factors of mortality in burn patients

Burn mortality statistics may be misleading unless they account properly for the many factors that can influence outcome. Such estimates are useful for patients and others making medical and financial decisions concerning their care. This study aimed to define the clinical, microbiological and laboratorial predictors of mortality with a view to focus on better burn care. Data were collected using independent variables, which were analyzed sequentially and cumulatively, employing univariate statistics and a pooled, cross-sectional, multivariate logistic regression to establish which variables better predict the probability of mortality. Survivors and non-survivors among burn patients were compared to define the predictive factors of mortality. Mortality rate was 5.0%. Higher age, larger burn area, presence of fungi in the wound, shorter length of stay and the presence of multi-resistant bacteria in the wound significantly predicted increased mortality. The authors conclude that those patients who are most apt to die are those with age > 50 years, with limited skin donor sites and those with multi-resistant bacteria and fungi in the wound.As estatisticas de mortalidade em queimaduras podem ser incompletas se nao levarem em consideracao varios fatores que podem influenciar o obito. Tradicionalmente, apenas a extensao da queimadura e a idade do paciente tem sido usadas como preditores de mortalidade em vitimas de queimaduras. Estas estimativas sao uteis na assistencia aos pacientes, interferindo em decisoes medicas e financeiras no cuidado desses doentes. O objetivo desse estudo foi definir os preditores clinicos, microbiologicos e laboratoriais de mortalidade em pacientes queimados. Os autores realizaram uma analise univariada e multivariada de varias variaveis independentes para determinar os fatores preditivos de mortalidade em queimados. A taxa de mortalidade foi de 5,0%. A idade mais avancada, a extensao das queimaduras, a presenca de fungo na ferida queimada e a presenca de bacteria multiresistente na ferida foram os fatores que mais aumentaram significativamente a mortalidade em pacientes queimados. Os autores concluem que os pacientes com maior probabilidade de obito sao os pacientes com idade superior a 50 anos, com queimaduras extensas, presenca de fungo e bacteria multiresistente na ferida.

Socioeconomic factors and attitudes towards household prevention of American cutaneous leishmaniasis in an endemic area in southern Bahia, Brazil

A survey was conducted to identify socioeconomic conditions and attitudes towards household prevention of American cutaneous leishmaniasis in Corte de Pedra, located in the county of Tancredo Neves, an endemic region in southern Bahia, Brazil. A questionnaire was applied in July 1997, focusing on social and economic variables, habits, and attitudes towards prevention of arthropod bites. All families (100%) living in the study area were surveyed, comprising 168 households with 851 individuals. Approximately 66.7% of the families earned up to one minimum wage, supporting an average of 5.1 residents per household. Most (57.2%) of the families did not use any type of protection against bites. Fumigation by burning various types of materials was the most customary form of prevention. Individual protection measures were rarely used. Since there was evidence of household and peridomiciliary transmission in the study area, use of impregnated bed nets is an alternative for intradomiciliary protection.

Paracoccidioidomicose no Hospital Universitário de Brasília

Seventy-six paracoccidioidomycosis patients attended at the university hospital of Brasilia from 1984 to 2005 were studied. 82.9% were male and the mean age was 42 years. 54.9% of the patients were engaged in farming activities. Among the patients with the chronic form, 87% were smokers and 55.3% consumed alcohol. Among 71 patients without HIV/AIDS coinfection: a) paracoccidioidomycosis was recurrent in 21 (29.6%); b) the chronic or mixed form affected 77.5% of patients, predominantly in the oropharynx (70.9%) and lungs (67.3%), with lymph node lesions in 29.8%, laryngeal lesions in 27.3% and cutaneous lesions in 16.4%; c) in the acute/subacute form, lymph node lesions predominated (81.3%), followed by cutaneous lesions in 43.8%, which resulted in severe disease in 62.5% and moderate disease in 37.5%. Five patients had HIV/AIDS coinfection and three of them presented disseminated fungal infection together with marked immunosuppression.Seventy-six paracoccidioidomycosis patients attended at the university hospital of Brasilia from 1984 to 2005 were studied. 82.9% were male and the mean age was 42 years. 54.9% of the patients were engaged in farming activities. Among the patients with the chronic form, 87% were smokers and 55.3% consumed alcohol. Among 71 patients without HIV/AIDS coinfection: a) paracoccidioidomycosis was recurrent in 21 (29.6%); b) the chronic or mixed form affected 77.5% of patients, predominantly in the oropharynx (70.9%) and lungs (67.3%), with lymph node lesions in 29.8%, laryngeal lesions in 27.3% and cutaneous lesions in 16.4%; c) in the acute/subacute form, lymph node lesions predominated (81.3%), followed by cutaneous lesions in 43.8%, which resulted in severe disease in 62.5% and moderate disease in 37.5%. Five patients had HIV/AIDS coinfection and three of them presented disseminated fungal infection together with marked immunosuppression.

Plasmodium vivax malaria: related factors to severity in the State of Maranhão, Brazil

INTRODUCTION Malaria caused by Plasmodium vivax species has shown signs of severity, recorded with increasing frequency in the medical literature. This study aimed to characterize the signs of severe malaria by Plasmodium vivax in the State of Maranhão, Brazil. METHODS A descriptive cohort study of patients assisted in the field and a historical and concurrent study of a series of cases among hospitalized patients were undertaken to identify the clinical and laboratory signs of severity. RESULTS A total of 153 patients were included in the study, 13 of whom were hospitalized. Males made up the majority, numbering 103 (67.3%). The age of the patients ranged from 10 to 70 years, 92.2% were natives of the State of Maranhão, and 65% of the patients had had malaria before. The average time elapsed between symptom onset and diagnosis among outpatients was three days, while among hospitalized patients this average reached 15.5 days, a statistically significant difference (p=0.001). The parasitemia ranged from 500 to 10,000 parasites/µl in 92.8% of cases. The clinical and laboratory manifestations of severity were vomiting and diarrhea, jaundice, drowsiness, mental confusion, seizures, loss of consciousness, agitation, bleeding, pale skin, coughing and dyspnea, thrombocytopenia, anemia, elevation of nitrogenous compounds, and elevated transaminases and bilirubin. CONCLUSIONS The monitoring of malaria patients with Plasmodium vivax showed the possibility of aggravation, the intensity of which varied in different circumstances, especially the interval time between falling ill and diagnostic confirmation.

Histopatologia da hepatite de Lábrea

A histopathological study of the liver in seven fatal cases of Labrea hepatitis with different survival times permitted a sequential assessment of the changes. The fundamental earlier lesions were acute fatty change, lytic and coagulative necrosis of isolated cells in all the lobules, without massive or zona! necrosis. Mononuclear leucocytic infiltration in portal spaces, features of cholestasis, proliferation of small biliary ducts and liver-cell regeneration appeared as later consequences from the sudden acute parenchymal injury. The histologic picture is characteristic but not pathognomonic and gives no clues as to the pathogenesis of the disease, whifch remains idhiopathic. The tiver is the main and primary organ affected in this disease, changes in other organs being mild and secondary.

Ação de mosquiteiros impregnados com deltametrina sobre a morbidade da malária em uma área da Amazônia Brasileira

In 1992 an investigation regarding the value of insecticide impregnated mosquito nets was conducted in the municipality of Costa Marques, Rondonia. Impregnated mosquito nets gave similar protection to those not impregnated, without modifying the incidence of infection during the season of low transmission. The multivariate analysis for age and antibody titre showed a significant protection of impregnated nets against the risk of infection only in the season of high transmission, when bed nets were used more correctly. There was no difference in the effect of both kinds of bed nets in the prevention of high parasitaemia. At the end of the study, there was a reduction of the prevalence of splenomegaly in both groups but hematocrit values rose to normal in the below 15 year olds using impregnated nets.In 1992 an investigation regarding the value of insecticide impregnated mosquito nets was conducted in the municipality of Costa Marques, Rondonia. Impregnated mosquito nets gave similar protection to those not impregnated, without modifying the incidence of infection during the season of low transmission. The multivariate analysis for age and antibody titre showed a significant protection of impregnated nets against the risk of infection only in the season of high transmission, when bed nets were used more correctly. There was no difference in the effect of both kinds of bed nets in the prevention of high parasitaemia. At the end of the study, there was a reduction of the prevalence of splenomegaly in both groups but hematocrit values rose to normal in the below 15 year olds using impregnated nets.