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SLE is more prevalent in populations of African (AA) than European ancestry (EA) and leucopenia is common. A homozygous variant inWe performed a retrospective cohort study in patients with SLE at a tertiary care system. Ancestry was defined by genetic principal components. We compared the rate of leucopenia, thrombocytopenia and anaemia between (a) EA and AA patients, and (b)The cohort included 574 patients of EA and 190 of AA;SLE of AA had higher rates of anaemia, leucopenia, and thrombocytopenia than those of EA; only the difference in leucopenia was explained by

Chagas disease affects 8-11 million people throughout the Americas. Early detection is crucial for timely treatment and to prevent non-vectorial transmission. Recombinant antigen-based rapid tests had high sensitivity and specificity in laboratory evaluations, but no Peruvian specimens were included in previous studies. We evaluated Stat-Pak and Trypanosoma Detect rapid tests in specimens from Bolivia and Peru. Specimens positive by three conventional assays were confirmed positives; specimens negative by two or more assays were confirmed negatives. In Bolivian specimens, Stat-Pak and Trypanosoma Detect tests were 87.5% and 90.7% sensitive, respectively; both showed 100% specificity. Sensitivity in Peruvian specimens was much lower: 26.6-33.0% (Stat-Pak) and 54.3-55.2% (Trypanosoma Detect); both had specificities > 98%. Even in Bolivian specimens, these sensitivities are inadequate for stand-alone screening. The low sensitivity in Peru may be related to parasite strain differences. Chagas disease rapid tests should be field tested in each geographic site before widespread implementation for screening. Copyright

We performed a cross-sectional study to determine the epidemiology of Cryptosporidium in human immunodeficiency virus (HIV)-infected persons at 3 diagnostic levels: microscopy, genotypes of Cryptosporidium, and subtype families of C. hominis and C. parvum. The study enrolled 2,490 HIV-infected persons in Lima, Peru, and 230 were microscopy positive for Cryptosporidium infection. Specimens from 193 participants were available for genotyping. They had C. hominis (141 persons), C. parvum (22 persons), C. meleagridis (17 persons), C. canis (6 persons), C. felis (6 persons), and C. suis (1 person) infection. Although microscopy results showed that Cryptosporidium infections were associated with diarrhea, only infections with C. canis, C. felis, and subtype family Id of C. hominis were associated with diarrhea, and infection with C. parvum was associated with chronic diarrhea and vomiting. These results demonstrate that different Cryptosporidium genotypes and subtype families are linked to different clinical manifestations.

The effects of HIV co-infection and multi-drug resistant tuberculosis (MDRTB) on tuberculosis prognosis are poorly defined. Therefore, we studied infectiousness and mortality of 287 tuberculosis patients treated with standard, directly observed, short-course therapy in the Peruvian community. During 6-17 months of treatment, 49 (18%) of patients died, of whom 48 (98%) had AIDS and 28 (57%) had MDRTB; 17/31 (55%) of MDRTB-patients with AIDS died within 2 months of diagnosis, before traditional susceptibility testing would have identified their MDRTB. Most non-MDRTB became smear- and culture-negative within 6 weeks of therapy, whereas most MDRTB remained sputum-culture-positive until death or treatment completion. HIV-negative patients with non-MDRTB had good outcomes. However, MDRTB was associated with prolonged infectiousness and HIV co-infection with early mortality, indicating a need for greater access to anti-retroviral therapy. Furthermore, early and rapid tuberculosis drug-susceptibility testing and infection control are required so that MDRTB can be appropriately treated early enough to reduce mortality and transmission.

Simple interventions may facilitate vector control and prevent periurban transmission of Chagas disease., In Arequipa, Peru, vectorborne transmission of Chagas disease by Triatoma infestans has become an urban problem. We conducted an entomologic survey in a periurban community of Arequipa to identify risk factors for triatomine infestation and determinants of vector population densities. Of 374 households surveyed, triatomines were collected from 194 (52%), and Trypanosoma cruzi–carrying triatomines were collected from 72 (19.3%). Guinea pig pens were more likely than other animal enclosures to be infested and harbored 2.38× as many triatomines. Stacked brick and adobe enclosures were more likely to have triatomines, while wire mesh enclosures were protected against infestation. In human dwellings, only fully stuccoed rooms were protected against infestation. Spatially, households with triatomines were scattered, while households with T. cruzi–infected triatomines were clustered. Keeping small animals in wire mesh cages could facilitate control of T. infestans in this densely populated urban environment.

Summary Introduction In developing countries, tuberculosis (TB) is responsible for almost 250000 deaths among children yearly. Active TB in children with human immunodeficiency virus (HIV) infection is difficult to diagnose and progresses rapidly to death. The aim of this preliminary study was to investigate the prevalence and clinical correlates of TB-related illness among HIV-infected children admitted to an infectious diseases ward in Peru, a country where TB is highly endemic. Method Forty-seven HIV-infected children admitted for a suspected infectious process in a Peruvian hospital were investigated for evidence of clinical tuberculosis by auramine stain, culture, and polymerase chain reaction (PCR) of clinical specimens. Results Eight children (17%) had evidence of tuberculosis, including five with positive cultures and three with positive PCR tests only. Weight loss was the only feature associated with a positive test for tuberculosis. Radiological changes were very common in both TB-positive and TB-negative groups and these changes were not useful to identify TB-positive cases. Conclusions Weight loss may be used to identify high-risk HIV positive children who require more aggressive evaluation for tuberculosis. Radiological changes were common in both TB-positive and TB-negative groups.

A three-step method for the purification of Enterocytozoon bieneusi spores from stool specimens was developed. The primary process of purification of the spores from bacterial contaminants involved Percoll gradient centrifugation followed by additional separation using cesium chloride density gradient centrifugation. The cesium chloride-isolated spores were further purified using a flow cytometer with cell sorting capabilities. Sorting was performed without the use of antibodies, fluorochromes, or dyes, leaving the sorted spores in their native state, which appears to be less destructive for spores. When quantified by flow cytometry using tubes with known numbers of highly fluorescent polystyrene beads, the sorted material showed a slight decrease in light scatter characteristics compared with the slightly larger Encephalitozoon species spores. Although the overall recovery of the E. bieneusi spores was low, calcofluor and Gram chromotrope staining, indirect immunofluorescence assay, and transmission electron microscopy revealed that the sorted material was highly purified and contained large numbers of E. bieneusi spores and relatively few bacteria and other debris. The sorted material appeared to be sufficiently pure and could be used for in vitro culture and for the development of a variety of diagnostic reagents as well as in studying the genome of E. bieneusi and host-parasite interactions.

Cryptosporidium parasites from a cross-sectional study conducted in two national hospitals in Lima, Peru were genetically characterized to determine the diversity of Cryptosporidium spp. in HIV-positive people. A total of 2,672 patients participated in this study and provided 13,937 specimens. Cryptosporidium oocysts were detected by microscopy in 354 (13.3%) of the patients. Analysis of 951 Cryptosporidium-positive specimens from 300 patients using a small subunit rRNA-based PCR-RFLP tool identified 6 genotypes; Cryptosporidium hominis was the species most frequently detected (67.5%), followed by C. meleagridis (12.6%) and C. parvum (11.3%). Cryptosporidium canis (4.0%), C. felis (3.3%), and Cryptosporidium pig genotype (0.5%) were also found. These findings indicate that C. hominis is the predominant species in Peruvian HIV-positive persons, and that zoonotic Cryptosporidium spp. account for about 30% of cryptosporidiosis in these patients.

Vector-borne transmission of Chagas disease has become an urban problem in the city of Arequipa, Peru, yet the debilitating symptoms that can occur in the chronic stage of the disease are rarely seen in hospitals in the city. The lack of obvious clinical disease in Arequipa has led to speculation that the local strain of the etiologic agent, Trypanosoma cruzi, has low chronic pathogenicity. The long asymptomatic period of Chagas disease leads us to an alternative hypothesis for the absence of clinical cases in Arequipa: transmission in the city may be so recent that most infected individuals have yet to progress to late stage disease. Here we describe a new method, epicenter regression, that allows us to infer the spatial and temporal history of disease transmission from a snapshot of a population's infection status. We show that in a community of Arequipa, transmission of T. cruzi by the insect vector Triatoma infestans occurred as a series of focal micro-epidemics, the oldest of which began only around 20 years ago. These micro-epidemics infected nearly 5% of the community before transmission of the parasite was disrupted through insecticide application in 2004. Most extant human infections in our study community arose over a brief period of time immediately prior to vector control. According to our findings, the symptoms of chronic Chagas disease are expected to be absent, even if the strain is pathogenic in the chronic phase of disease, given the long asymptomatic period of the disease and short history of intense transmission. Traducción al español disponible en Alternative Language Text S1/A Spanish translation of this article is available in Alternative Language Text S1, Author Summary Chagas disease has become an urban problem in the city of Arequipa, Peru, yet there are very few people exhibiting severe symptoms of the disease. Severe symptoms often do not appear until decades after infection. To determine why so few people were exhibiting severe symptoms, we used a new method, epicenter regression, to trace the history of Chagas disease transmission in a community of Arequipa, Peru. Our findings suggest that transmission in Arequipa occurred through a series of small epidemics, the oldest of which began only around 20 years ago. These micro-epidemics infected nearly 5% of the community before the insect that carries Chagas disease, Triatoma infestans, was eliminated by insecticide application. Most human infections in the study community arose over a brief period of time immediately prior to the insecticide application. According to our findings, the severe symptoms of Chagas disease are expected to be absent from the community because of the short duration of infection with the parasite, even among older individuals with Chagas disease.

Chagas disease affects an estimated 8 million people in Latin America. Infected individuals have 20–30% lifetime risk of developing cardiomyopathy, but more subtle changes in autonomic responses may be more frequent. We conducted a matched case-control study of children in Arequipa, Peru, where triatomine infestation and Trypanosoma cruzi infection are emerging problems. We collected data on home environment, history, physical examination, electrocardiogram, and autonomic testing. Signs of triatomine infestation and/or animals sleeping in the child's room and household members with Chagas disease were associated with increased infection risk. Electrocardiogram findings did not differ between cases and controls. However, compared with control children, infected children had blunted autonomic responses by three different measures, the Valsalva maneuver, the cold pressor test, and the orthostatic test. T. cruzi-infected children show autonomic dysfunction, although the prognostic value of this finding is not clear. Sustained vector control programs are essential to decreasing future T. cruzi infections.

Pulmonary tuberculosis diagnosis is difficult when patients cannot produce sputum. Most sputum is swallowed, and tuberculosis DNA can survive intestinal transit. We therefore evaluated molecular testing of stool specimens for detecting tuberculosis originating from the lungs. Paired stool and sputum samples ( n = 159) were collected from 89 patients with pulmonary tuberculosis. Control stool samples ( n = 47) were collected from patients without tuberculosis symptoms. Two techniques for DNA extraction from stool samples were compared, and the diagnostic accuracy of the PCR in stool was compared with the accuracy of sputum testing by PCR, microscopy, and culture. A heminested IS 6110 -PCR was used for tuberculosis detection, and IS 6110 -PCR-positive stool samples then underwent rifampin sensitivity testing by universal heteroduplex generator PCR (heteroduplex-PCR) assay. For newly diagnosed pulmonary tuberculosis patients, stool IS 6110 -PCR had 86% sensitivity and 100% specificity compared with results obtained by sputum culture, and stool PCR had similar sensitivities for HIV-positive and HIV-negative patients ( P = 0.3). DNA extraction with commercially available spin columns yielded greater stool PCR sensitivity than DNA extraction with the in-house Chelex technique ( P = 0.007). Stool heteroduplex-PCR had 98% agreement with the sputum culture determinations of rifampin resistance and multidrug resistance. Tuberculosis detection and drug susceptibility testing by stool PCR took 1 to 2 days compared with an average of 9 weeks to obain those results by traditional culture-based testing. Stool PCR was more sensitive than sputum microscopy and remained positive for most patients for more than 1 week of treatment. In conclusion, stool PCR is a sensitive, specific, and rapid technique for the diagnosis and drug susceptibility testing of pulmonary tuberculosis and should be considered when sputum samples are unavailable.

Diagnosis of Chagas disease is hindered by discordance between screening and confirmatory test results for Trypanosoma cruzi infection. In periurban Arequipa, Peru, spatial analysis revealed that individuals with discordant test results are spatially clustered in hotspots of T. cruzi transmission, suggesting that discordant results likely represent true infections in this setting.

Chagas disease affects 8-11 million people throughout the Americas. Early detection is crucial for timely treatment and to prevent non-vectorial transmission. Recombinant antigen-based rapid tests had high sensitivity and specificity in laboratory evaluations, but no Peruvian specimens were included in previous studies. We evaluated Stat-Pak and Trypanosoma Detect rapid tests in specimens from Bolivia and Peru. Specimens positive by three conventional assays were confirmed positives; specimens negative by two or more assays were confirmed negatives. In Bolivian specimens, Stat-Pak and Trypanosoma Detect tests were 87.5% and 90.7% sensitive, respectively; both showed 100% specificity. Sensitivity in Peruvian specimens was much lower: 26.6-33.0% (Stat-Pak) and 54.3-55.2% (Trypanosoma Detect); both had specificities98%. Even in Bolivian specimens, these sensitivities are inadequate for stand-alone screening. The low sensitivity in Peru may be related to parasite strain differences. Chagas disease rapid tests should be field tested in each geographic site before widespread implementation for screening.

Background. Chagas disease, caused by Trypanosoma cruzi infection, is an urban problem in Arequipa, Peru, and the epidemiology of Chagas disease is likely to be quite different in this area, compared with in rural zones. Methods. We conducted a serosurvey of 1615 children

The effects of HIV co-infection and multi-drug resistant tuberculosis (MDRTB) on tuberculosis prognosis are poorly defined. Therefore, we studied infectiousness and mortality of 287 tuberculosis patients treated with standard, directly observed, short-course therapy in the Peruvian community. During 6–17 months of treatment, 49 (18%) of patients died, of whom 48 (98%) had AIDS and 28 (57%) had MDRTB; 17/31 (55%) of MDRTB-patients with AIDS died within 2 months of diagnosis, before traditional susceptibility testing would have identified their MDRTB. Most non-MDRTB became smear- and culture-negative within 6 weeks of therapy, whereas most MDRTB remained sputum-culture-positive until death or treatment completion. HIV-negative patients with non-MDRTB had good outcomes. However, MDRTB was associated with prolonged infectiousness and HIV co-infection with early mortality, indicating a need for greater access to anti-retroviral therapy. Furthermore, early and rapid tuberculosis drug-susceptibility testing and infection control are required so that MDRTB can be appropriately treated early enough to reduce mortality and transmission.

A cross-sectional study was conducted to examine the genotype distribution of Enterocytozoon bieneusi in HIV-infected patients who visited two government hospitals in Lima, Peru from January 2000 through March 2003. Microsporidia were detected by microscopy in 105 (3.9%) of 2,672 patients. A total of 212 stool samples from 89 microsporidia-positive patients were genotyped by sequence analysis of the internal transcribed spacer (ITS) region of the rRNA gene. A 392-bp fragment containing the complete ITS region was amplified and sequenced. Multiple alignments and phylogenetic analysis of these ITS sequences identified 11 distinct genotypes of E. bieneusi (Peru-1 to Peru-11), 6 of which were new genotypes not reported before. The remaining 5 genotypes had nucleotide sequences identical to those previously reported in humans, cats, pigs, and wild mammals. All the 11 E. bieneusi-genotypes identified are genetically related, and members of the group have been previously found in humans, domestic animals, and some wild mammals. Thus, there is a high genetic diversity of E. bieneusi in humans in Peru, and zoonotic transmission is possible if humans are in close contact with infected animals.