Plasmodium vivax and Plasmodium falciparum infection in Neotropical primates in the western Amazon, Brazil.

The Brazilian Amazon is endemic for malaria and natural infections by Plasmodium spp. have been detected in Neotropical primates. Despite the diversity of primate species in the region, studies on infections by these agents are limited. The aim of the present study was to investigate the frequency of infection by Plasmodium vivax and P. falciparum in free-born primates that were kept in captivity, in the western Amazon, Brazil. Blood samples were collected from 98 Neotropical primates. Detection of P. vivax and P. falciparum DNA was performed using a semi-nested PCR, and the amplified products were sequenced. Plasmodium spp. DNA was detected in 6.12% (6/98) of the primates. P. vivax, and P. falciparum DNA was detected in 2.04% (2/98) and 4.08% (4/98) of these mammals, respectively. Sequencing and phylogenetic analysis confirmed the results obtained from the semi-nested PCR. The presence of infected non-human primates (NHP) can be auxiliary in the maintenance of P. falciparum and P. vivax and may have implications for the malaria surveillance and control in the Brazilian Amazon. It is necessary to structure an efficient surveillance system for the aetiological agents of malaria that infect NHP and humans to reduce the risk of Plasmodium spp. introduction into new areas, to protect all susceptible species.

New records of Amblyomma goeldii (Acari: Ixodidae) and description of the nymphal stage.

Since its original description from the Amazonian region, the tick species Amblyomma goeldii Neumann, 1899 has been misidentified with Amblyomma rotundatum Koch, 1844 in different countries of the Neotropical region. Because of this, some authors have considered that the only confirmed records of A. goeldii were from French Guyana. Herein, we reviewed all specimens of A. goeldii that have been deposited at two tick collections in Brazil. In addition, we describe the nymphal stage of A. goeldii for the first time. A total of 10 unpublished records of the adult stage of A. goeldii are recorded from the Amazonian region of Brazil, confirming the occurrence of A. goeldii in this country. Except for one record on the snake Boa constrictor Linnaeus, all records of A. goeldii reported in the present study were from anteaters (Pilosa: Myrmecophagidae). Our results, in conjunction with previous literature records, indicate that anteaters and large snakes are important hosts for the adult stage of A. goeldii. The nymph of A. goeldii is morphologically similar to the nymphs of Amblyomma romitii Tonelli-Rondelli, 1939, Amblyomma dissimile Koch, 1844, and A. rotundatum. We present a modification of a previously published taxonomic key of Amblyomma nymphs from Brazil, in order to perform taxonomic identification of the nymph of A. goeldii based on external morphology. The geographical distribution of A. goeldii appears to be restricted to the Amazonian region. There were no previous host records for the immature stages of A. goeldii, thus it is expected that the present nymphal description will facilitate further works on the ecology of this poorly studied tick species.

Characterization of monocyte-derived dendritic cells from patients with active and treated paracoccidioidomycosis.

Cellular immune responses are a significant defence mechanism in human paracoccidioidomycosis (PCM), an endemic mycosis in Latin America; however, little is known about the role of dendritic cells (DCs) in human PCM. We investigated monocyte-derived DCs from patients with treated (TP) and active PCM (AP) compared with healthy non-PCM donors (CO). DCs from the TP group showed higher expression of HLA-DR, CD86 and DC-SIGN compared with CO, whereas AP showed similar expression to CO. Production of IL-10 was downregulated by TNF-α in all groups and lower levels were observed in untreated DCs from AP compared with CO. Conversely, IL-12p40 was significantly upregulated in the DCs of the TP group. TNF-α-activated DCs from the CO group produced significantly lower levels of IL-12p40 when differentiated from magnetic-sorted monocytes (MACS) compared with adhered monocyte-derived DCs. This comparison in the TP group revealed similar levels of IL-12p40, suggesting a T cell-independent increase in the production of IL-12p40. Higher expression of surface molecules with increased IL-12p40 may indicate a better activation of DCs after the treatment of PCM. Our findings suggest that DCs may be crucial in the protective response to Paracoccidioides brasiliensis and that in vitro-generated DCs might be useful in enhancing antifungal immunity, especially during active PCM.

Experimental infection and horizontal transmission of Bartonella henselae in domestic cats.

In order to study B. henselae transmission among cats, five young cats were kept in confinement for two years, one of them being inoculated by SC route with B. henselae (10(5) UFC). Only occasional contact among cats occurred but the presence of fleas was observed in all animals throughout the period. Blood culture for isolation of bacteria, PCR-HSP and FTSZ (gender specific), and BH-PCR (species-specific), as well as indirect immunofluorescence method for anti-B. henselae antibodies were performed to confirm the infection of the inoculated cat as well as the other naive cats. Considering the inoculated animal, B. henselae was first isolated by blood culture two months after inoculation, bacteremia last for four months, the specific antibodies being detected by IFI during the entire period. All contacting animals presented with bacteremia 6 months after experimental inoculation but IFI did not detect seroconversion in these animals. All the isolates from these cats were characterized as Bartonella (HSP and FTSZ-PCR), henselae (BH-PCR). However, DNA of B. henselae could not be amplified directly from peripheral blood by the PCR protocols used. Isolation of bacteria by blood culture was the most efficient method to diagnose infection compared to PCR or IFI. The role of fleas in the epidemiology of B. henselae infection in cats is discussed.

Avaliaçäo do sistema complemento em crianças, em diversos estádios da infecçäo pelo HIV: correlaçäo clínico-laboratorial / Evaluation of complement system in children in different phases of HIV infection: clinical and laboratorial correlation

Objetivo: A ativaçäo do complemento foi demonstrada em pacientes adultos infectados pelo HIV, no entanto, poucas informaçöes estäo disponíveis em crianças infectadas no período perinatal. O objetivo do presente estudo foi analisar a funçäo do sistema complemento em crianças infectads pelo HIV. Método: 127 crianças infectads pelo HIV no período neonatal (onze a 134 meses, 62 do sexo masculino: 65 do sexo feminino) foram incluídas e classificadas de acordo com os critérios clínicos e imunológicos do Centro de Controle de Doenças (Atlanta, EUA), de 1994. O diagnóstico da ativaçäo do sistema complemento foi realizado pelos seguintes ensaios: CH50 para via clássica, APH50 para via alternativa (APH50), ELISA para via das lectinas (MBL) e 'rocket' imunoeletroforese para o produto de C3,C3dg/C3d. Resultados: As infecçöes mais freqüentes foram: pneumonia bacteriana, otite, diarréia e infecçöes oportunistas como pneumonia por Pneumocystis carinii e tuberculose (31,5 por cento). A miocardiopatia foi a única apresentaçäo clínica que se relacionou com o estado imunológico (categoria 3). Nenhuma diferença estatisticamente significante nas funçöes da via clássica e alternativa foi observada entre os pacientes das diferentes categorias. Valores médios aumentados de CH50, APH50 e MBL foram verificados em pacientes nos estádios mais avançados da doença. Níveis elevados de C3d na maioria dos pacientes indicam que o complemento encontra-se ativado durante a infecçäo pelo HIV em crianças. CH50, APH50, e MBL estavam abaixo dos limites inferiores em duas, dez e duas crianças, respectivamente.

[Hereditary angioedema: clinical and laboratory aspects of 7 cases]. / Angioedema hereditário: aspectos clínico-laboratoriais de sete casos.

Hereditary angioedema is caused by a defect in C1 inhibitor activity (C1INH). Its occurrence is rare and it is associated with an autosomal dominant mode of inheritance. We describe seven patients (4M:3F), age from 12 to 50 years old, who are affected by hereditary angioedema; four of them belong to the same family. The main clinical manifestations were: angioedema of face, hands and feet (6/7) and abdominal pain (2/7). No triggering factors were associated with symptoms in 4/7 patients and trauma (2/7) and menses (1/7) were reported in the other three ones. One patient was submitted to laparotomy for partial intestinal resection, before diagnosis. Laboratory complement analysis revealed the absence of hemolytic function of complement, reduced C4 (6/7) and low C1INH levels. All patients received Danazol (100 mg/day) with clinical control. Hereditary angioedema has to be considered in the differential diagnosis of angioedema, since an early diagnosis of this immunodeficiency, leading to specific treatment in order to decrease the complications.

[Immunological behavior (IgG, IgM, IgA) and total complement (CH50) of newborns infants with risk factors for early onset sepsis. Comparative analysis of newborns with and without infection]. / Comportamento imunológico (IgG, IgM, IgA) e complemento total (CH 50) de recém-nascidos com fatores de risco para sepse precoce. Análise comparativa entre recém-nascidos com e sem infecção.

Immunological behavior (IgG, IgM, IgA) and total Complement (CH50) of newborns infants with risk factors for early onset sepsis. Comparative analysis between newborns with and without infection. Rev. Hosp. Clín. Fac. Med. S. Paulo, 53(6): 303-310, 1998. The objective of this study was to verify the immunological behavior of the newborn infant in front of an infection. We studied 60 newborn infants that had risk factors for early onset sepsis (premature rupture membranes, clinic amnionitis or tract urinary infection) from de immunological and infection point of view. They were classified into three gestational age groups: < 34 weeks, between 34 and 36 6/7 weeks and > or = 37 weeks. Sepsis diagnosis was done through clinical and laboratorial data and we also included the followings exams: Immunological types (IgG, IgM, IgA) and total complement (CH50) obtained from the newborn at birth and on the fifth day of life. We could verify that 15 newborns (25%) presented early sepsis. There was a statistical association between perinatal asfixia and infection in the group with gestational age < 34 weeks and this same group presented statistical association between infection and death. The serical levels of IgG and CH50 were directly related to the gestational age and there were significant statistical differences between levels of IgG, IgM and total Complement between infected and not infected newborns within the same group os gestional age. We observed that the infection was associated to low levels of IgG and CH50, at birth and on the fifth day, mainly in the group of infected newborns with gestional age < 34 weeks, being this group, therefore, the one that would mostly benefit from an immunological support in front of and infection.

Brazilian report on primary immunodeficiencies in children: 166 cases studied over a follow-up time of 15 years.

One hundred sixty-six cases of primary immunodeficiency diseases (PID) (95 males, 71 females), diagnosed according to WHO criteria, have been registered at the Children's Hospital, University of São Paulo, Brazil. The following frequencies were found: predominantly humoral defects, 60.8% (n = 101); T cell defects, 4.9% (n = 8); combined ID, 9.6% (n = 16); phagocyte disorders, 18.7% (n = 31); and complement deficiencies, 6% (n = 10). IgA deficiency was the most frequent disorder (n = 60), followed by transient hypogammaglobulinemia (n = 14), chronic granulomatous disease (n = 14), and X-linked agammaglobulinemia (n = 9). In comparison to other (national) reports, we observed higher relative frequencies of phagocyte and complement deficiencies. Recurrent infections were the cause of death in 12.7%. Allergic symptoms were observed in 41%, mainly in IgA-deficient, hypogammaglobulinemic, or hyper-IgE patients, and autoimmune disorders in 5%, predominantly in IgA and complement deficiencies. Five patients suffered from BCG dissemination; two of them died. This is the first Brazilian report on PID over an observation time of 15 years.

PIP: Over a 15-year observation period (1981-96), 166 cases of primary immunodeficiency disease (PID) were registered at the Department of Pediatrics, University of Sao Paulo, Brazil. PID was diagnosed according to World Health Organization criteria and only children with well-established deficiencies were included. The following frequencies were noted by PID classification: predominantly humoral defects (60.8%), T cell defects (4.9%), combined immunodeficiency (9.6%), phagocyte disorders (18.7%), and complement deficiencies (6%). The male to female ratio was 1.3 to 1. Immunoglobin A deficiency was the most frequent disorder (60 cases), followed by transient hypogammaglobulinemia (14 cases), chronic granulomatous disease (14 cases), and X-linked agammaglobulinemia (9 cases). Allergic symptoms occurred in 41% of cases. During the observation period, 23 children (13.8%) died, primarily of recurrent infections. Although improved diagnostic facilities have facilitated the recognition of immunodeficient children, the true incidence is likely to be higher than that detected in this study. Increased international collaboration is urged to improve the early detection of PID.