The epidemiology of acute viral gastroenteritis in hospitalized children in Cordoba city, Argentina: an insight of disease burden

Information concerning the disease burden of viral gastroenteritis has important implications for the use and monitoring the impact of public health policies. The present study, carried out in Córdoba city, Argentina, documents the epidemiology of severe viral diarrhea as well as the burden of viral gastrointestinal disease in the hospital children admission. A total of 133 stools were collected from hospitalized children (Town Childhood Hospital) suffering from acute diarrhea and studied for the presence of Group A rotavirus, astrovirus and adenovirus 40/41 by enzyme-immuno assay, between November 1997 and October 1998. Enteric viruses accounted for 42.1% of the total diarrheal cases analyzed. Group A rotaviruses, astroviruses, adenoviruses 40/41 and mixed infections were found in 35.3, 4.5, 1.5, and 0.8% studied specimens respectively. We estimated that 1 in 27 children in the 0-35 month-old cohort/range would be annually hospitalized for a viral gastroenteritis illness. The major impact on viral diarrhea lies on rotaviral infection, accouting for 84.0% of the viral diarrheal cases analyzed and for approximately one third of severe diarrheas requiring hospital admission in Córdoba City, Argentina.

The association between serum potassium at hospital admission and the case-fatality rate of leptospirosis in men

Severe leptospirosis affects predominantly males and presents a high susceptibility to hypokalemic acute renal failure. As hypokalemia and hyperkalemia induce severe complications, it is important to evaluate if the initial serum potassium is an independent risk factor for death in leptospirosis. The medical records of 1016 patients hospitalized with the diagnosis of leptospirosis were reviewed. The analysis was restricted to 442, according to the following criteria: male, 18 years or older, information about death or hospital discharge and recorded values of serum potassium, serum creatinine and duration of symptoms at admission. Potassium values lower than 3.5 mEq/L (hypoK), 3.5-5 mEq/L (normoK) and above 5 mEq/L (hyperK) were detected in 180, 245 and 17 patients, respectively. The death rate increased with serum potassium: 11.1% in the hypoK, 14.7% in the normoK and 47.1% in the hyperK group (p = 0.002). In a logistic regression model (normoK as referent), including age, creatinine and duration of symptoms, hypoK was not associated with increased death rate (odds ratio (OR) = 0.80; p > 0.1). On the other hand, hyperK showed a significant association with increased risk of death (OR = 3.95, p = 0.021). In conclusion, in this sample of men with leptospirosis initial serum potassium was positively and independently correlated with the risk of in-hospital death.

Serologic survey for hantavirus infections among wild animals in rural areas of São Paulo State, Brazil

A serosurvey was conducted in wild animals captured close to two areas where hantavirus cardiopulmonary syndrome (HCPS) occurred in São Paulo State, Brazil. Serum samples from a total of 43 mammals were tested for antibodies reactive with Sin Nombre (SN) hantavirus using a strip immunoblot assay. RNAs from the blood clots of the positive samples were submitted to reverse transcriptase-polymerase chain reaction (RT-PCR). Two rodents of the genus Oligoryzomys were positive for hantavirus antibodies. These animals were captured in the Iguape region and represented 16.7% (2/12) of the sera from rodents and 100.0% (2/2) of the Oligoryzomys captured in that area. RT-PCR failed to amplify any viral cDNA. These results are in agreement with other data that suggest that members of this genus are important reservoirs of hantaviruses in Brazil.

Diagnosis of cytomegalovirus infections by qualitative and quantitative PCR in HIV infected patients

A high incidence of cytomegalovirus (CMV) infections is observed in Brazil. These viruses are causatives of significant morbidity and mortality among patients with advanced human immunodeficiency virus (HIV) infection. This work, shows the application of a PCR on determination of CMV load in the buffy coat and plasma. We analyzed the samples of 247 HIV infected patients in order to diagnose CMV infection and disease. We developed a semi-quantitative PCR that amplifies part of the glycoprotein B (gB) gene of CMV. The semi-quantitative PCR was carried out only in positive clinical samples in a qualitative PCR confirmed by a nested-PCR. CD4 lymphocyte count, HIV viral load and CMV disease symptom were correlated with CMV load. CMV genome was detected in the buffy coat of 82 of 237 (34.6%) patients, in 10 of these the CMV load was determined varying between 928 and 332 880 viral copies/mug DNA. None of these 237 patients developed any suggestive manifestation of CMV disease. For the other 10 HIV infected patients selected based on the suspicion of CMV disease, CMV genome was detected in only one case. This patient presented a high CMV load, 8 000 000 copies/mug DNA, and developed a disseminated form of CMV disease including hepatitis and retinitis. Our results were greatly influenced by the impact of the highly active antiretroviral therapy that reduced incidence of CMV viremia and occurrence of CMV disease in the HIV infected patients.

Evaluation of surrogate markers for human immunodeficiency virus infection among blood donors at the blood bank of "Hospital Universitário Regional Norte do Paraná", Londrina, PR, Brazil

This study evaluated the usefulness of the anti-HBc, hepatitis C virus antibodies (anti-HCV), human T cell lymphotropic virus I and II antibodies (anti-HTLV I/II), serologic tests for syphilis, and surface antigen of hepatitis B virus (HBsAg) as surrogate markers for the risk for HIV infection in 80,284 serum samples from blood donors from the Blood Bank of "Hospital Universitário Regional Norte do Paraná", Londrina, Paraná State, Brazil, analyzed from July 1994 to April 2001. Among 39 blood donors with positive serology for HIV, 12 (30.8%) were anti-HBc positive, 10 (25.6%) for anti-HCV, 1 (2.6%) for anti-HTLV I/I, 1 (2.6%) was positive for syphilis, and 1 (2.6%) for HBsAg. Among the donors with negative serology for HIV, these markers were detected in 8,407 (10.5%), 441 (0.5%), 189 (0.2%), 464 (0.6%), and 473 (0.6%) samples, respectively. The difference was statistically significant (p < 0.001) for anti-HBc and anti-HCV. Although the predictive positive value for these surrogate markers were low for HIV infection, the results confirmed the anti-HBc and anti-HCV as useful surrogate markers for HIV infection thus reinforcing the maintenance of them in the screening for blood donors contributing to the prevention of the small number of cases in which HIV is still transmitted by transfusion.

Accidental tetanus: prognosis evaluation in a historical series at a hospital in Salvador, Bahia, Brazil

A total of 868 (84.89%) patients diagnosed with tetanus were studied, out of the 1,024 tetanus patients hospitalized at Couto Maia Hospital (Salvador, Bahia, Brazil), during the period between 1986 and 1997. Of this group (n = 868), 63.5% (n = 551) were discharged, 35.4% (n = 307) died, and 1.1% (n = 10) were transferred. The average age of the deceased patients (38.73 ± 23.31 years) was significantly greater (p < 0.0001) than the age of those who survived (29.21 ± 20.05 years). Analyzing the variables of the logistic regression model with statistic significance (p £ 0.25) for univariate analysis, we observed a greater association of risk for worst prognosis (death) in patients aged ³ 51 years; time of illness < 48 hours; time of incubation < 168 hours; neck rigidity; spasms; opisthotonos; body temperature ³ 37.7 ºC; heart beat ³ 111 beats/minute; sympathetic hyperactivity and association with pneumonia. Among the group of those who survived, patients with 1 to 5 of those variables (n = 398; 76.8%) were more frequent, while among patients of the group of the deceased, 70.3% (n = 206) presented 6 to 10 of those variables, with a highly significant difference (p < 10-8). In conclusion, the indicators described provide early information that may guide the prognosis and medical and nurse care.

Human T-cell lymphotropic virus types I and II infections in a cohort of patients with neurological disorders in Belém, Pará, Brazil

Serum- and/or- cerebrospinal fluid (CSF) samples obtained from 190 patients suffering from chronic, progressive neurological disease were screened for the presence of human T-cell lymphotropic viruses type I (HTLV-I) and type II (HTLV-II) antibodies over a six-year period (1996 to 2001) in Belém, Pará, Brazil. Patients were of both sexes (male subjects, 52%) with ages ranging from 2 to 79 years (mean, 35.9). Overall, 15 (7.9%) subjects - of whom 12 (80%) were female adults - reacted HTLV-I/II-seropositive when screened by enzyme-linked immunosorbent assay (ELISA). Serum samples from 14 of these patients were also analyzed using a recombinant Western blot (WB) assay that yielded HTLV-I-, HTLV-II-, and HTLV-I/II- reactivities for 10 (71.4%), 3 (21.4%) and 1 (7.2%) of them, respectively. The yearly rates of HTLV-I/II antibodies ranged from 2.6% (2001) to 21.7% (2000), with progressively increasing seropositivities from 1998 to 2000. Altogether, walking difficulty (n = 5 subjects), spasticity (n = 4) and leg weakness (n = 3) accounted for 80% of symptoms recorded among the 15 patients whose sera had antibodies to HTLV-I/II as detected by ELISA. These findings provide evidence that both HTLV-I and HTLV-II play a role in the development of chronic myelopathy in Belém, Pará, Northern Brazil.

Comparative study of the in-hospital case-fatality rate of leptospirosis between pediatric and adult patients of different age groups

The main objective was to compare the in-hospital case-fatality rate of leptospirosis between pediatric (< 19 years) and adult (>19 years) patients, taking into account gender, renal function, duration of symptoms and jaundice. Medical records of 1016 patients were reviewed. Comparative analysis was restricted to 840 patients (100 pediatric, 740 adults) with recorded information on the variables included in the analysis. Among these patients 81.7% were male and 91.5% were icteric. The case-fatality rate of leptospirosis was 14.4%. The odds of death adjusted for gender, jaundice, duration of symptoms, serum urea and serum creatinine were almost four times higher for the adult than for the pediatric group (odds ratio (OR) = 3.94; 95% confidence interval = 1.19-13.03, p = 0.029). Among adults, increased age was also significantly and independently associated with increased risk of death (p < 0.01). Older patients were also more often treated by dialysis. In conclusion, the data suggest that the in-hospital case fatality rate of leptospirosis is higher for adults than for children and adolescents, even after taking into account the effects of several potential risk factors of death. Among adults, older age was also strongly and independently associated with higher risk of death.

Childhood astrovirus-associated diarrhea in the ambulatory setting in a Public Hospital in Cordoba city, Argentina

Human astroviruses have been increasingly identified as important agents of diarrheal disease in children. However, the disease burden of astrovirus infection is still incompletely assessed. This paper reports results on the epidemiological and clinical characteristics of astrovirus-associated diarrhea, as well as the impact of astrovirus infection on the ambulatory setting at a Public Hospital in Córdoba city, Argentina. From February 2001 through January 2002, 97 randomly selected outpatient visits for diarrhea among children < 36 months old were enrolled. A single specimen of stool from each child was collected and tested for astrovirus antigen by enzyme immunoassay. Astroviruses were detected in 12.37% of the diarrheal episodes. All the positive cases occurred in children 4 to 18 months, but the highest rate was in children aged 4 to 6 months (23.80%). The clinical symptoms of astrovirus associated-diarrhea were fever 41.66%, vomiting 25.00% and dehydration 8.33%; overall 16.66% required hospitalization. Astrovirus was identified through the year and no seasonally pattern was detected (cool semester 15.21% versus warm semester 9.80% p > 0.05). According to our estimation about one out of seventy-four children in this cohort would be assisted annually for an astroviral-diarrheal episode in the Public Hospital and one out of eight diarrheal cases could be attributed to astrovirus infection. Astrovirus is a common symptomatic infection in pediatric outpatient visits in the public hospital in the study area, contributing 12.37% of the overall morbidity from diarrhea.

Orbital tuberculosis diagnosed by immunohistochemistry: case reports

PURPOSE: To describe three cases of orbital tuberculosis, with their clinical characteristics and respective diagnostic procedures, showing the importance of histopathology for the correct diagnosis. PATIENTS AND METHODS: Three patients diagnosed and treated for orbital tuberculosis, in the "Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo" during the years of 1999 and 2001. RESULTS: All of the patients were female and referred a chronic evolution of swelling of one eyelid associated or not with other symptoms. They had not HIV infection. Two of them had positive epidemiology for tuberculosis. However, the search for systemic evidence of the disease and staining for bacilli (Ziehl-Neelsen method) were negative in all three patients. In all the cases, only the biopsy with immunohistochemical analysis could confirm the diagnosis. COMMENTS: Orbital involvement is a rare ocular manifestation of tuberculosis. Even in a tertiary hospital, few cases, if any, are diagnosed per year. However, the global incidence and prevalence of M. tuberculosis infections is not under control yet, and it has been a serious public health problem. Thus, one must be aware of the possibility of tuberculosis among the orbital diseases.

Cutaneous anthrax in Lima, Peru: retrospective analysis of 71 cases, including four with a meningoencephalic complication

Anthrax is a zoonosis produced by Bacillus anthracis, and as an human infection is endemic in several areas in the world, including Peru. More than 95% of the reported naturally acquired infections are cutaneous, and approximately 5% of them can progress to meningoencephalitis. In this study we review the clinical and epidemiological characteristics of the patients with diagnosis of cutaneous anthrax evaluated between 1969 and 2002 at the Hospital Nacional Cayetano Heredia (HNCH) and the Instituto de Medicina Tropical Alexander von Humboldt in Lima, Peru. Seventy one patients were included [49/71 (69%) of them men], with a mean age of 37 years. The diagnoses were classified as definitive (44%) or probable (56%). The most common occupation of the patients was agriculture (39%). The source of infection was found in 63 (88.7%) patients. All the patients had ulcerative lesions, with a central necrosis. Most of the patients (65%) had several lesions, mainly located in the upper limbs (80%). Four patients (5.6%) developed meningoencephalitis, and three of them eventually died. In conclusion, considering its clinical and epidemiological characteristics, cutaneous anthrax must be included in the differential diagnosis of skin ulcers. A patient with clinical suspicion of the disease should receive effective treatment soon, in order to avoid neurological complications which carry a high fatality rate.

Incidence of respiratory viruses in preterm infants submitted to mechanical ventilation

The objectives of this study were to determine the incidence of infection by respiratory viruses in preterm infants submitted to mechanical ventilation, and to evaluate the clinical, laboratory and radiological patterns of viral infections among hospitalized infants in the neonatal intensive care unit (NICU) with any kind of acute respiratory failure. Seventy-eight preterm infants were studied from November 2000 to September 2002. The newborns were classified into two groups: with viral infection (Group I) and without viral infection (Group II). Respiratory viruses were diagnosed in 23 preterm infants (29.5%); the most frequent was respiratory syncytial virus (RSV) (14.1%), followed by influenza A virus (10.2%). Rhinorrhea, wheezing, vomiting and diarrhea, pneumonia, atelectasis, and interstitial infiltrate were significantly more frequent in newborns with nosocomial viral infection. There was a correlation between nosocomial viral infection and low values of C-reactive protein. Two patients with mixed infection from Group I died during the hospital stay. In conclusion, RSV was the most frequent virus in these patients. It was observed that, although the majority of viral lower respiratory tract infections had a favorable course, some patients presented a serious and prolonged clinical manifestation, especially when there was concomitant bacterial or fungal infection.

Screening for pulmonary tuberculosis in Teresópolis, RJ, Brazil: the search for respiratory symptomatic patients in emergency service of "Hospital das Clínicas de Teresópolis Costantino Ottaviano, Fundação Educacional Serra dos Órgãos"

The aim of the present study was to investigate the detection percentage of tuberculosis among patients that are respiratory symptomatic (TB suspects). In this work, we present the preliminary results of research carried out at "Hospital das Clínicas de Teresópolis Costantino Ottaviano da Fundação Educacional Serra dos Órgãos (FESO)" from November 2003 to April 2004. Among the 40 respiratory symptomatic individuals identified and referred to the Tuberculosis Control Program in Teresópolis, two (5.0%) were characterized as smear-positive. These results confirm reports in the literature and underscore the need for and importance of this strategy.

Rapid turnover of Plasmodium falciparum var gene transcripts and genotypes during natural non-symptomatic infections

The var genes of Plasmodium falciparum code for the antigenically variant erythrocyte membrane proteins 1 (PfEMP1), a major factor for cytoadherence and immune escape of the parasite. Herein, we analyzed the var gene transcript turnover in two ongoing, non-symptomatic infections at sequential time points during two weeks. The number of different circulating genomes was estimated by microsatellite analyses. In both infections, we observed a rapid turnover of plasmodial genotypes and var transcripts. The rapidly changing repertoire of var transcripts could have been caused either by swift elimination of circulating var-transcribing parasites stemming from different or identical genetic backgrounds, or by accelerated switching of var gene transcription itself.