Clinical and diagnostic aspects of intestinal microsporidiosis in HIV-infected patients with chronic diarrhea in Rio de Janeiro, Brazil

The objectives of this study were to determine both the prevalence of microsporidial intestinal infection and the clinical outcome of the disease in a cohort of 40 HIV-infected patients presenting with chronic diarrhea in Rio de Janeiro, Brazil. Each patient, after clinical evaluation, had stools and intestinal fragments examined for viral, bacterial and parasitic pathogens. Microsporidia were found in 11 patients (27.5%) either in stools or in duodenal or ileal biopsies. Microsporidial spores were found more frequently in stools than in biopsy fragments. Samples examined using transmission electron microscopy (n=3) or polymerase chain reaction (n=6) confirmed Enterocytozoon bieneusi as the causative agent. Microsporidia were the only potential enteric pathogens found in 5 of the 11 patients. Other pathogens were also detected in the intestinal tract of 21 patients, but diarrhea remained unexplained in 8. We concluded that microsporidial infection is frequently found in HIV infected persons in Rio de Janeiro, and it seems to be a marker of advanced stage of AIDS.

Etiology of acute diarrhea among children in Ribeirão Preto-SP, Brazil

To study the main enteropathogens causing diarrhea in the region of Ribeirão Preto regarding serogroups and serotypes, the feces of 1836 children under 10 years old, from both sexes, attack of acute gastroenteritis, were analysed during a period of 4 years in Adolfo Lutz Institute - Ribeirão Preto, SP. The pathogens identified by standard methods were the following: Escherichia coli, Salmonella spp., Shigella spp., Campylobacter spp., Yersinia spp., and Cryptosporidium spp. Positive samples were 22.8% (419) with 1.7% association of pathogens. Larger isolates were mainly from children 0 to 11 months old. Enteropathogenic E. coli (EPEC) was most frequent (8.7%) with predominance of serogroup O119 (40.2%), followed by Shigella (6.2%), 63.6% of which S. sonnei.

Whipple's disease. Report of five cases with different clinical features

Whipple's disease (WD) is a rare systemic disease of infectious etiology which involves the small intestine but can virtually affect any organ. We present here five cases (four males and one female) ranging in age from 20 to 59 years. All patients had intestinal involvement associated or not with clinical manifestations linked to this organ. Vegetation in the tricuspid valve was observed in one patient, suggesting endocarditis caused by Tropheryma whippelii, with disappearance of the echocardiographic alterations after treatment. In one of the male patients the initial clinical manifestation was serologically negative spondylitis, with no diarrhea occurring at any time during follow-up. Ocular involvement associated with intestinal malabsorption and significant weight loss were observed in one case. In the other two cases, diarrhea was the major clinical manifestation. All patients were diagnosed by histological examination of the jejunal mucosa and, when indicated, of extraintestinal tissues by light and electron microscopy. After antibiotic treatment, full remission of symptoms occurred in all cases. A control examination of the intestinal mucosa performed after twelve months of treatment with sulfamethoxazole-trimethoprim revealed the disappearance of T. whippelii in four patients. The remaining patient was lost to follow-up.

Microbicidal effect of medicinal plant extracts (Psidium guajava Linn. and Carica papaya Linn.) upon bacteria isolated from fish muscle and known to induce diarrhea in children

Out of the twenty-four samples of shrimp and fish muscle used for this study, twelve were collected near a large marine sewer for waste disposal, 3 km off the coast of Fortaleza (Brazil) and used for the isolation of E. coli. Other twelve were collected at the Mucuripe fresh fish market (Fortaleza, Brazil) and used for the isolation of Staphylococcus aureus. Ethanol, water and acetone-diluted extracts of guava and papaya leaf sprouts were tested on the bacteria in order to verify their microbicidal potential. The E. coli strains used in the trials were rated LT positive. The papaya leaf extracts (Carica papaya Linn) showed no microbicidal activity while the guava sprout extracts (Psidium guajava Linn) displayed halos exceeding 13 mm for both species, an effect considered to be inhibitory by the method employed. Guava sprout extracts by 50% diluted ethanol most effectively inhibited E. coli (EPEC), while those in 50% acetone were less effective. It may be concluded that guava sprout extracts constitute a feasible treatment option for diarrhea caused by E. coli or by S. aureus-produced toxins, due to their quick curative action, easy availability in tropical countries and low cost to the consumer.

Infectious agents in coronary atheromas: a possible role in the pathogenesis of plaque rupture and acute myocardial infarction

In this review we report our recent findings of histopathological features of plaque instability and the association with Mycoplasma pneumoniae (MP) and Chlamydia pneumoniae (CP) infection, studying thrombosed coronary artery segments (CAS) of patients who died due to acute myocardial infarction. Vulnerable plaques are known to be associated with fat atheromas and inflammation of the plaque. Here we demonstrated that vulnerability is also related with focal positive vessel remodeling that maintains relatively well preserved lumen even in the presence of large atheromatous plaques. This phenomena may explain why the cinecoronariography may not detect large and dangerous vulnerable plaques. Greater amount of these bacteria in vulnerable plaques is associated with adventitial inflammation and positive vessel remodeling: the mean numbers of lymphocytes were significantly higher in adventitia than in the plaque, good direct correlation was obtained between numbers of CD20 B cells and numbers of CP infected cells in adventitia, and between % area of MP-DNA in the plaque and cross sectional area of the vessel, suggesting a cause-effect relationship. Mycoplasma is a bacterium that needs cholesterol for proliferation and may increase virulence of other infectious agents. In conclusion, co-infection by Mycoplasma pneumoniae and Chlamydia pneumoniae may represent an important co-factor for plaque instability, leading to coronary plaque thrombosis and acute myocardial infarction, since larger amount of these bacteria strongly correlated with histological signs of more vulnerability of the plaque. The search of CMV and Helicobacter pilori in these tissues resulted negative.

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.

Relationship of cryptosporidiosis to abdominal pain and diarrhea in Mayan Indians

Demonstration of cryptosporidiosis in Mayan Indians living around Lake Atitlan provided an opportunity to correlate infection with abdominal pain and/or diarrhea in different age groups of children. 94 subjects experiencing abdominal pain and/or diarrhea, between the ages of 2 and 13 were studied in towns around Lake Atitlan, Guatemala, over a two-year period. Cryptosporidium oocysts were found in the feces of 29% of children who presented with abdominal pain and 21% with diarrhea. Of the 60 infected subjects, 45% were experiencing abdominal pain and 33% diarrhea, 22% had abdominal pain and diarrhea. Both abdominal pain and diarrhea were significantly higher in children under 10 years of age and were most prevalent in the 6-9 year old age group but the correlation of symptoms to infection was not significantly different as the ages of the children increased. The high frequency of abdominal pain and/or diarrhea with infection in children was consistent with cryptosporidiosis, a disease considered as one of several common intestinal infections that produce these symptoms.

Prevalence and associated risk factors for Giardia lamblia infection among children hospitalized for diarrhea in Goiânia, Goiás State, Brazil

The objective of this study was to determine the prevalence and to identify risk factors associated with Giardia lamblia infection in diarrheic children hospitalized for diarrhea in Goiânia, State of Goiás, Brazil. A cross-sectional study was conducted and a comprehensive questionnaire was administered to the child's primary custodian. Fixed effects logistic regression was used to determine the association between infection status for G. lamblia and host, sociodemographic, environmental and zoonotic risk factors. A total of 445 fecal samples were collected and processed by the DFA methodology, and G. lamblia cysts were present in the feces of 44 diarrheic children (9.9%). A variety of factors were found to be associated with giardiasis in these population: age of children (OR, 1.18; 90% CI, 1.0 - 1.36; p = 0.052), number of children in the household (OR 1.45; 90% CI, 1.13 - 1.86; p = 0.015), number of cats in the household (OR, 1.26; 90% CI, 1.03 -1.53; p = 0.059), food hygiene (OR, 2.9; 90% CI, 1.34 - 6.43; p = 0.024), day-care centers attendance (OR, 2.3; 90% CI, 1.20 - 4.36; p = 0.034), living on a rural farm within the past six months prior hospitalization (OR, 5.4; CI 90%, 1.5 - 20.1; p = 0.03) and the number of household adults (OR, 0.59; 90% CI, 0.42 - 0.83; p = 0.012). Such factors appropriately managed may help to reduce the annual incidence of this protozoal infection in the studied population.

Prevalence of intestinal microsporidiosis in Human Immunodeficiency Virus-infected patients with diarrhea in major United States cities

To determine the prevalence of intestinal microsporidiosis in HIV-infected patients, we performed a prospective study of HIV-infected patients with diarrheal illnesses in three US hospitals and examined an observational database of HIV-infected patients in 10 US cities. Among 737 specimens from the three hospitals, results were positive for 11 (prevalence 1.5%); seven (64%) acquired HIV through male-to-male sexual contact, two (18%) through male-to-male sexual contact and injection drug use, and one (9%) through heterosexual contact; one (9%) had an undetermined mode of transmission. Median CD4 count within six months of diagnosis of microsporidiosis was 33 cells/µL (range 3 to 319 cells/µL). For the national observational database (n = 24,098), the overall prevalence of microsporidiosis was 0.16%. Prevalence of microsporidiosis among HIV-infected patients with diarrheal disease is low, and microsporidiosis is most often diagnosed in patients with very low CD4+ cell counts. Testing for microsporidia appears to be indicated, especially for patients with very low CD4+ cell counts.

Antibacterial activity of GUAVA, Psidium guajava Linnaeus, leaf extracts on diarrhea-causing enteric bacteria isolated from Seabob shrimp, Xiphopenaeus kroyeri (Heller)

Guava leaf tea of Psidium guajava Linnaeus is commonly used as a medicine against gastroenteritis and child diarrhea by those who cannot afford or do not have access to antibiotics. This study screened the antimicrobial effect of essential oils and methanol, hexane, ethyl acetate extracts from guava leaves. The extracts were tested against diarrhea-causing bacteria: Staphylococcus aureus, Salmonella spp. and Escherichia coli. Strains that were screened included isolates from seabob shrimp, Xiphopenaeus kroyeri (Heller) and laboratory-type strains. Of the bacteria tested, Staphylococcus aureus strains were most inhibited by the extracts. The methanol extract showed greatest bacterial inhibition. No statistically significant differences were observed between the tested extract concentrations and their effect. The essential oil extract showed inhibitory activity against S. aureus and Salmonella spp. The strains isolated from the shrimp showed some resistance to commercially available antibiotics. These data support the use of guava leaf-made medicines in diarrhea cases where access to commercial antibiotics is restricted. In conclusion, guava leaf extracts and essential oil are very active against S. aureus, thus making up important potential sources of new antimicrobial compounds.

Pseudo-outbreak of Clostridium difficile associated diarrhea (CDAD) in a tertiary-care hospital

The objective of this study was to describe a pseudo-outbreak of C. difficile in a hospital, following a change in the method used to detect the toxin. In February 2002, there were two cases of CDAD and in March 7 occurred, coinciding with a change of the test (from detection of toxin A to toxin A/B). An outbreak was suspected. Active surveillance and education of staff were started. A CDAD case was defined as a patient with acute onset of diarrhea (³ three episodes of liquid stools) and a positive stool test. They were classified as hospital or community-acquired. Stool samples were also collected for C. difficile culture and isolates were typed using AP-PCR. From March 2002 through December 2003 there were 138 cases of CDAD: 70% were hospital-acquired and among the 30% with CDAD present on admission, most (81%) came directly from the community (50% had no history of hospitalization). Fifty-two percent of hospital-acquired CDAD and 94% of cases on admission had already used antibiotics. The incidence of CDAD in hospitalized patients during surveillance was 3.3 per 1000 patient-admissions. The incidence of CDAD present on admission was 6.1/1000 patients. Sixteen isolates were typed and presented 13 different profiles. In conclusion, the CDAD increase in our study occurred due to change in diagnostic methods and not due to an outbreak, as suspected initially. The incidence in hospitalized patients was much lower than in reported outbreaks. There were 13 molecular types suggesting that an outbreak did not occur. CDAD was largely community-acquired.

Whipple's disease: rare disorder and late diagnosis

Whipple's disease is a rare systemic infectious disorder caused by the bacterium Tropheryma whipplei. We report the case of a 61-year-old male patient who presented to emergency room complaining of asthenia, arthralgia, anorexia, articular complaints intermittent diarrhea, and a 10-kg weight loss in one year. Laboratory tests showed the following results: Hb = 7.5 g/dL, albumin = 2.5 mg/dL, weight = 50.3 kg (BMI 17.4 kg/m²). Upper gastrointestinal endoscopy revealed areas of focal enanthema in the duodenum. An endoscopic biopsy was suggestive of Whipple's disease. Diagnosis was confirmed based on a positive serum polymerase chain reaction. Treatment was initiated with intravenous ceftriaxone followed by oral trimethoprim-sulfamethoxazole. After one year of treatment, the patient was asymptomatic, with Hb = 13.5 g/dL, serum albumin = 5.3 mg/dL, and weight = 70 kg (BMI 24.2 kg/m²). Whipple's disease should be considered a differential diagnosis in patients with prolonged constitutional and/or gastrointestinal symptoms. Appropriate antibiotic treatment improves the quality of life of patients.