RESUMEN
BACKGROUND: Histoplasmosis is acquired by inhalation of spores of the dimorphic fungus Histoplasma spp. Although this pathogen is distributed worldwide, it is more prevalent in the Americas. However, the real burden of histoplasmosis remains undefined in many endemic regions. METHODOLOGY: We conducted a series of 61 autopsies to individuals who died in a hospital in the Brazilian Amazon focused on infectious diseases. We performed a detailed histological and microbiological evaluation with genetic characterization of Histoplasma strains with the aim to evaluate the contribution of histoplasmosis to morbidity and mortality. Additionally, we assessed the clinicopathological correlation. PRINCIPAL FINDINGS: Evidence of Histoplasma infection was detected in 21 patients (34%). Eight cases were disseminated infections, all of them occurred in HIV-positive patients. Six cases were localized histoplasmosis, limited to the lungs. In seven patients Histoplasma DNA was detected by PCR in patients with no histological lesions. Histoplasma infection was detected in 38% of HIV-positive patients and was a major contributor to death in 22% of them. Lungs, liver and spleen were affected in all cases of disseminated histoplasmosis. Phylogenetic analysis of the strains suggested a high diversity of Histoplasma species circulating in the Brazilian Amazon. Histoplasmosis was clinically missed in 75% of the disseminated infections. CONCLUSIONS: The high incidence of histoplasmosis, the low index of clinical suspicion, and the severity of the disseminated disease highlight the need of proactively implementing sensitive routine screening methods for this pathogen in endemic areas. Antifungal prophylaxis against Histoplasma should be encouraged in the severely immunocompromised HIV patients in these areas. In conclusion, substantial mortality is associated with disseminated histoplasmosis among HIV-positive patients in the Brazilian Amazon.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Histoplasma/clasificación , Histoplasma/genética , Histoplasmosis/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Autopsia , Brasil/epidemiología , Femenino , Histoplasmosis/mortalidad , Histoplasmosis/patología , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Prevalencia , Adulto JovenRESUMEN
Rotavirus vaccines have been adopted in African countries since 2009, including Mozambique (2015). Disease burden data are needed to evaluate the impact of rotavirus vaccine. We report the burden of rotavirus-associated diarrhea in Mozambique from the Global Enteric Multicenter Study (GEMS) before vaccine introduction. Methods: A case-control study (GEMS), was conducted in Manhiça district, recruiting children aged 0-59 months with moderate-to-severe diarrhea (MSD) and less-severe-diarrhea (LSD) between December 2007 and November 2012; including 1-3 matched (age, sex and neighborhood) healthy community controls. Clinical and epidemiological data and stool samples (for laboratory investigation) were collected. Association of rotavirus with MSD or LSD was determined by conditional logistic regression and adjusted attributable fractions (AF) calculated, and risk factors for rotavirus diarrhea assessed. Results: Overall 915 cases and 1,977 controls for MSD, and 431 cases and 430 controls for LSD were enrolled. Rotavirus positivity was 44% (217/495) for cases and 15% (160/1046) of controls, with AF = 34.9% (95% CI: 32.85-37.06) and adjusted Odds Ratio (aOR) of 6.4 p< 0.0001 in infants with MSD compared to 30% (46/155) in cases and 14% (22/154) in controls yielding AF = 18.7%, (95% CI: 12.02-25.39) and aOR = 2.8, p = 0.0011 in infants with LSD. The proportion of children with rotavirus was 32% (21/66) among HIV-positive children and 23% (128/566) among HIV-negative ones for MSD. Presence of animals in the compound (OR = 1.9; p = 0.0151) and giving stored water to the child (OR = 2.0, p = 0.0483) were risk factors for MSD; while animals in the compound (OR = 2.37, p = 0.007); not having routine access to water on a daily basis (OR = 1.53, p = 0.015) and washing hands before cooking (OR = 1.76, p = 0.0197) were risk factors for LSD. Conclusion: The implementation of vaccination against rotavirus may likely result in a significant reduction of rotavirus-associated diarrhea, suggesting the need for monitoring of vaccine impact.
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Humanos , Masculino , Femenino , Niño , Infecciones por Rotavirus/inmunología , Infecciones por Rotavirus/epidemiología , Rotavirus/inmunología , Vacunas contra Rotavirus/inmunología , Mozambique , Modelos LogísticosRESUMEN
Multidrug-resistant Escherichia coli ST131 fimH30 responsible for extra-intestinal pathogenic (ExPEC) infections is globally distributed. However, the occurrence of a subclone fimH27 of ST131 harboring both ExPEC and enteroaggregative E. coli (EAEC) related genes and belonging to commonly reported O25:H4 and other serotypes causing bacteremia in African children remain unknown. We characterized 325 E. coli isolates causing bacteremia in Mozambican children between 2001 and 2014 by conventional multiplex polymerase chain reaction and whole genome sequencing. Incidence rate of EAEC bacteremia was calculated among cases from the demographic surveillance study area. Approximately 17.5% (57/325) of isolates were EAEC, yielding an incidence rate of 45.3 episodes/105 children-years-at-risk among infants; and 44 of isolates were sequenced. 72.7% (32/44) of sequenced strains contained simultaneously genes associated with ExPEC (iutA, fyuA and traT); 88.6% (39/44) harbored the aggregative adherence fimbriae type V variant (AAF/V). Sequence type ST-131 accounted for 84.1% (37/44), predominantly belonging to serotype O25:H4 (59% of the 37); 95.6% (35/44) harbored fimH27. Approximately 15% (6/41) of the children died, and five of the six yielded ST131 strains (83.3%) mostly (60%; 3/5) due to serotypes other than O25:H4. We report the emergence of a new subclone of ST-131 E. coli strains belonging to O25:H4 and other serotypes harboring both ExPEC and EAEC virulence genes, including agg5A, associated with poor outcome in bacteremic Mozambican children, suggesting the need for prompt recognition for appropriate management.
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Humanos , Bacteriemia/epidemiología , Escherichia coli/clasificación , Niño , Mozambique/epidemiologíaRESUMEN
Background Clinico-pathological discrepancies are more frequent in settings in which limited diagnostic techniques are available, but there is little information on their actual impact. Aim We assessed the accuracy of the clinical diagnoses in a tertiary referral hospital in sub-Saharan Africa by comparison with post-mortem findings. We also identified potential risk factors for misdiagnoses. Methods One hundred and twelve complete autopsy procedures were performed at the Maputo Central Hospital (Mozambique), from November 2013 to March 2015. We reviewed the clinical records. Major clinico-pathological discrepancies were assessed using a modified version of the Goldman and Battle classification. Results Major diagnostic discrepancies were detected in 65/112 cases (58%) and were particularly frequent in infection-related deaths (56/80 [70%] major discrepancies). The sensitivity of the clinical diagnosis for toxoplasmosis was 0% (95% CI: 037), 18% (95% CI: 252) for invasive fungal infections, 25% (95% CI: 557) for bacterial sepsis, 34% (95% CI: 1657), for tuberculosis, and 46% (95% CI: 1975) for bacterial pneumonia. Major discrepancies were more frequent in HIV-positive than in HIV-negative patients (48/73 [66%] vs. 17/39 [44%]; p = 0.0236). Conclusions Major clinico-pathological discrepancies are still frequent in resource constrained settings. Increasing the level of suspicion for infectious diseases and expanding the availability of diagnostic tests could significantly improve the recognition of common life-threatening infections, and thereby reduce the mortality associated with these diseases. The high frequency of clinico-pathological discrepancies questions the validity of mortality reports based on clinical data or verbal autopsy.
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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Enfermedades Transmisibles/mortalidad , Causas de Muerte , Errores Diagnósticos/estadística & datos numéricos , Enfermedades Transmisibles/diagnóstico , Centros de Atención Terciaria/estadística & datos numéricosRESUMEN
The uncertainty about the real burden of causes of death (CoD) is increasingly recognized by the international health community as a critical limitation for prioritizing effective public health measures. The minimally invasive autopsy (MIA) has shown to be a satisfactory substitute of the complete diagnostic autopsy (CDA), the gold standard for CoD determination in low- and middle-income countries. However, more studies are needed to confirm its adequate performance in settings with different epidemiology. In this observational study, the CoD obtained with the MIA were compared with the clinical diagnosis and the results of the CDA in 61 deaths that occurred in an infectious diseases referral hospital in Manaus, Brazilian Amazon. Concordance between the categories of diseases obtained by the three methods was evaluated by the Kappa statistic. Additionally, we evaluated discrepancies between clinical and complete diagnostic autopsy diagnoses. The MIA showed a substantial concordance with the CDA (Kappa = 0.777, 95% CI 0.608-0.946), and a perfect or almost perfect coincidence in specific diagnosis (ICD-10 code) between MIA and CDA was observed in 85% of the cases. In contrast, the clinical diagnosis showed a fair concordance with the CDA (Kappa = 0.311, 95% CI 0.071-0.552). Major clinico-pathological discrepancies were identified in 49% of cases. In conclusion, the MIA showed a substantial performance for CoD identification. Clinico-pathological discrepancies remain high and justify the need for post-mortem studies, even in referral hospitals. The MIA is a robust substitute of the CDA for CoD surveillance and quality improvement of clinical practice in low- and middle-income settings.
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Autopsia/métodos , Causas de Muerte , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
: Invasive pneumococcal disease (IPD) is a major cause of illness and death among children worldwide. 10-valent pneumococcal conjugate vaccine (PCV10) was introduced as part of the Mozambican routine immunization program in April 2013. We characterized the IPD burden in a rural area of Mozambique before PCV introduction and estimated the potential impact of this intervention. Methods: We conducted population-based surveillance for IPD, defined as S. pneumoniae isolated from blood or cerebrospinal fluid, among children <5 years old admitted to Manhiça District Hospital, a referral hospital in a rural area with high prevalence of human immunodiciency virus infection. S. pneumoniae was identified using standard microbiologic methods and serotyped using sequential multiplex PCR or Quellung. IPD incidence was calculated among cases from a defined catchment area. Results: From January 2001 through December 2012, we isolated 768 cases of IPD, 498 (65%) of which were bacteraemic pneumonia episodes. A total of 391 (51%) were from the catchment area, yielding IPD incidence rates of 479, 390 and 107 episodes per 100,000 children-years at risk among children <12, 12-23 and 24-<60 months old, respectively. The overall IPD incidence fluctuated and showed a downward trend over time. In these same age groups, in-hospital death occurred in 48 (17%), 26 (12%), and 21 (13%) of all IPD cases, respectively. Overall 90% (543/603) of IPD isolates were available for serotyping; of those, 65% were covered by PCV10 and 83% by PCV13. Among 77 hospital deaths associated with serotyped IPD, 49% and 69% were caused by isolates included in the PCV10 and PCV13, respectively. Conclusions: We describe very high rates of IPD among children in rural Mozambique that were declining before PCV introduction. Children <1 year old have the greatest incidence and case fatality; although the rates remain high among older groups as well. Most IPD episodes and many deaths among children <5 years old will likely be prevented through PCV10 introduction in Mozambique.
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Humanos , Masculino , Femenino , Preescolar , Niño , Streptococcus pneumoniae/inmunología , Preescolar , Infecciones Neumocócicas/epidemiología , Recién Nacido , Mozambique/epidemiologíaRESUMEN
Background: Pregnant women exposed to Plasmodium falciparum generate antibodies against VAR2CSA, the parasite protein that mediates adhesion of infected erythrocytes to the placenta. There is a need of high-throughput tools to determine the fine specificity of these antibodies that can be used to identify immune correlates of protection and exposure. Here we aimed at developing a multiplex-immunoassay to detect antibodies against VAR2CSA antigens. Methods and findings: We constructed two multiplex-bead arrays, one composed of 3 VAR2CSA recombinant-domains (DBL3X, DBL5Æ and DBL6Æ) and another composed of 46 new peptides covering VAR2CSA conserved and semi-conserved regions. IgG reactivity was similar in multiplexed and singleplexed determinations (Pearson correlation, protein array: R2 = 0.99 and peptide array: R2 = 0.87). IgG recognition of 25 out of 46 peptides and all recombinant-domains was higher in pregnant Mozambican women (n = 106) than in Mozambican men (n = 102) and Spanish individuals (n = 101; p<0.05). Agreement of IgG levels detected in cryopreserved plasma and in elutions from dried blood spots was good after exclusion of inappropriate filter papers. Under heterogeneous levels of exposure to malaria, similar seropositivity cutoffs were obtained using finite mixture models applied to antibodies measured on pregnant Mozambican women and average of antibodies measured on pregnant Spanish women never exposed to malaria. The application of the multiplex-bead array developed here, allowed the assessment of higher IgG levels and seroprevalences against VAR2CSA-derived antigens in women pregnant during 2003-2005 than during 2010-2012, in accordance with the levels of malaria transmission reported for these years in Mozambique.
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Humanos , Femenino , Adulto , Adulto Joven , Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/inmunología , Plasmodium falciparum/aislamiento & purificación , Inmunoglobulina G/sangre , Embarazo , Inmunoensayo , Anticuerpos Antiprotozoarios/inmunología , Malaria Falciparum/diagnóstico , Eritrocitos/parasitología , Pruebas con Sangre Seca , Antígenos de Protozoos/genética , Antígenos de Protozoos/metabolismoRESUMEN
The disappearance of lytic, protective antibodies (Abs) from the serum of patients with Chagas disease is accepted as a reliable indicator of parasitological cure. The efficiency of a chemiluminescent enzyme-linked immunosorbent assay based on a purified, trypomastigote-derived glycosylphosphatidylinositol-anchored mucin antigen for the serologic detection of lytic Abs against Trypanosoma cruzi was evaluated in a nonendemic setting using a panel of 92 positive and 58 negative human sera. The technique proved to be highly sensitive {100%; 95% confidence interval (CI) = 96-100} and specific (98.3%; 95% CI = 90.7-99.7), with a kappa score of 0.99. Therefore, this assay can be used to detect active T. cruzi infection and to monitor trypanosomicidal treatment.
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Anticuerpos Antiprotozoarios/sangre , Enfermedad de Chagas/diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , Trypanosoma cruzi/inmunología , Antígenos de Protozoos , Estudios de Casos y Controles , Glicosilfosfatidilinositoles , Humanos , LuminiscenciaRESUMEN
OBJECTIVE: Haemophilus influenzae type b (Hib) conjugate vaccine has dramatically reduced invasive Hib disease worldwide. Yet, data on protection against pneumonia and among children with HIV are limited. We evaluated the impact of Hib conjugate vaccine introduction in 2009 in a rural, high-HIV prevalence area in Mozambique. STUDY DESIGN: From 2006-2011, we conducted hospital-based surveillance for invasive Hib disease and clinical pneumonia (classified as severe and very severe) among children <5 years of age. Incidences calculated using population denominators were compared between baseline (2006-2008) and post-Hib conjugate vaccine (2010-2011) periods. Surveillance data for radiologically-confirmed pneumonia among children <2 years of age in 2011 were compared with baseline data from 2004-2006. RESULTS: Among 50 cases of invasive Hib disease, 5 occurred after Hib conjugate vaccine introduction; 1 case-patient was age-eligible for Hib conjugate vaccine (and had received 3 doses). Four post-Hib conjugate vaccine case-patients (including Hib conjugate vaccine failure) had HIV. Among children <1 and <5 years of age, significant reductions occurred in rates of invasive Hib disease (91% and 85%, respectively) and very severe pneumonia (29% and 34%, respectively). Radiologically-confirmed pneumonia incidence fell significantly (33%) in children <2 years of age. Severe pneumonia incidence did not decline. CONCLUSIONS: We demonstrate important reductions in invasive disease and pneumonia following Hib conjugate vaccine introduction in a high-HIV area. Continued surveillance is needed to monitor long-term Hib conjugate vaccine effects, particularly among children with HIV.
Asunto(s)
Infecciones por Haemophilus/epidemiología , Infecciones por Haemophilus/prevención & control , Vacunas contra Haemophilus/administración & dosificación , Haemophilus influenzae tipo b/inmunología , Neumonía Bacteriana/epidemiología , Neumonía Bacteriana/prevención & control , Cápsulas Bacterianas/inmunología , Preescolar , Infecciones por VIH/inmunología , Infecciones por Haemophilus/inmunología , Vacunas contra Haemophilus/inmunología , Humanos , Programas de Inmunización , Lactante , Mozambique/epidemiología , Neumonía Bacteriana/inmunología , Vigilancia de la Población , Prevalencia , Población RuralRESUMEN
Background: Pneumonia is the major cause of mortality and morbidity in children worldwide. Procalcitonin (PCT) and Creactive protein (CRP) are used in developed countries to differentiate between viral and bacterial causes of pneumonia. Validity of these markers needs to be further explored in Africa. Methodology and Principal Findings: We assessed the utility of PCT and CRP to differentiate viral from invasive bacterial pneumonia in children ,5 years hospitalized with clinical severe pneumonia (CSP) in rural Mozambique, a malaria-endemic area with high HIV prevalence. Prognostic capacity of these markers was also evaluated. Out of 835 children with CSP, 87 fulfilled definition of viral pneumonia and 89 of invasive bacterial pneumonia. In absence of malaria parasites, levels of PCT and CRP were lower in the viral group when compared to the invasive bacterial one (PCT: median = 0.21 versus 8.31 ng/ml, p,0.001; CRP: 18.3 vs. 185.35 mg/l, p,0.001). However, in presence of malaria parasites distribution between clinical groups overlapped (PCT: median = 23.1 vs. 21.75 ng/ml, p = 0.825; CRP: median = 96.8 vs. 217.4 mg/l, p = 0.052). None of the two markers could predict mortality. Conclusions: Presence of malaria parasites should be taken into consideration, either for clinical or epidemiological purposes, if using PCT or CRP to differentiate viral from invasive bacterial pneumonia in malaria-endemic areas.