Serological and molecular study of Hepatitis E virus in pediatric patients in Mexico.

INTRODUCTION AND OBJECTIVES: Cases of viral hepatitis reported in Mexico are typically identified as hepatitis A, B and C. However, unspecified cases are reported annually. Hepatitis E virus (HEV) is an emergent agent that causes a self-limiting infection that can evolve to chronic in immunosuppressed individuals. In Mexico, HEV genotype 2 is considered endemic, though it's the prevalence is not well known. Therefore, the present study was designed to determine the prevalence of HEV among patients at the "Hospital Infantil de Mexico Federico Gomez". MATERIALS AND METHODS: The study included 99 patients, anti-HEV antibody (IgG and IgM) were detected by indirect ELISA and viral genome was identified using RT-PCR technique. Two PCR products of positive cases were sequenced. RESULTS: ELISA results were positive in 3% and 6%, for IgG and IgM respectively, 54.5% prevalence was found by PCR. Low lymphocyte count (p<0.05) and malnutrition (p<0.005) were significant factors for high PCR prevalence and could increase the possibility of infection. Two samples were sequenced and confirmed the presence of HEV genotype 3. CONCLUSIONS: This report reveals the incidence of HEV in pediatric patients in Mexico. Moreover, the identification of HEV genotype 3 in human samples suggests a potential zoonotic risk that requires further research.

Study of macro and microelements in fish from the Cienfuegos Bay. Relationship with its content in sediments.

Thirteen microelements (Al, As, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Ti, V, and Zn) and four macroelements (Ca, K, Mg, and Na) were determined in the edible muscle tissue of fish in Cienfuegos Bay. Eight species, Albula vulpes, Diapterus rhombeus, Gerres cinereus, Haemulon carbonarium, Haemulon sciurus, Micropogonias furnieri, Kyphosus sectatrix, and Lutjanus cyanopterus were studied. The total concentrations and extracted concentrations using HCl were also determined in sediments. The quality of the analysis was guaranteed by validating the used analytical methods with certified reference materials of fish and sediments. The high content of macroelements confirmed the importance of fish as a valuable source of food for the local population. New information is provided on bioaccumulation of toxic elements As, Cd, Cu, Zn, and Cr in fish of the bay, with concentrations that overcame the local or international maximum allowable levels for human consumption in most samples analyzed. A high correlation between the content of toxic elements As, Cd, Zn, and macroelement K in fish and its concentration extracted from sediments using the HCl extraction method was observed.

Incidence rates and trends of hip/femur fractures in five European countries: comparison using e-healthcare records databases.

Hip fractures represent a major public health challenge worldwide. Multinational studies using a common methodology are scarce. We aimed to estimate the incidence rates (IRs) and trends of hip/femur fractures over the period 2003-2009 in five European countries. The study was performed using seven electronic health-care records databases (DBs) from Denmark, The Netherlands, Germany, Spain, and the United Kingdom, based on the same protocol. Yearly IRs of hip/femur fractures were calculated for the general population and for those aged ≥50 years. Trends over time were evaluated using linear regression analysis for both crude and standardized IRs. Sex- and age-standardized IRs for the UK, Netherlands, and Spanish DBs varied from 9 to 11 per 10,000 person-years for the general population and from 22 to 26 for those ≥50 years old; the German DB showed slightly higher IRs (about 13 and 30, respectively), whereas the Danish DB yielded IRs twofold higher (19 and 52, respectively). IRs increased exponentially with age in both sexes. The ratio of females to males was ≥2 for patients aged ≥70-79 years in most DBs. Statistically significant trends over time were only shown for the UK DB (CPRD) (+0.7% per year, P < 0.01) and the Danish DB (-1.4% per year, P < 0.01). IRs of hip/femur fractures varied greatly across European countries. With the exception of Denmark, no decreasing trend was observed over the study period.

Antidepressant prescribing in five European countries: application of common definitions to assess the prevalence, clinical observations, and methodological implications.

PURPOSE: Drug utilization studies have applied different methods to various data types to describe medication use, which hampers comparisons across populations. The aim of this study was to describe the time trends in antidepressant prescribing in the last decade and the variation in the prevalence, calculated in a uniform manner, in seven European electronic healthcare databases. METHODS: Annual prevalence per 10,000 person-years (PYs) was calculated for 2001-2009 in databases from Spain, Germany, Denmark, the United Kingdom (UK), and the Netherlands. Prevalence data were stratified according to age, sex, antidepressant type (selective serotonin re-uptake inhibitors [SSRIs] or tricyclic antidepressants [TCAs]) and major indications. RESULTS: The age- and sex-standardized prevalence was lowest in the two Dutch (391 and 429 users per 10,000 PYs) and highest in the two UK (913 and 936 users per 10,000 PYs) populations in 2008. The prevalence in the Danish, German, and Spanish populations was 637, 618, and 644 users per 10,000 PY respectively. Antidepressants were prescribed most often in 20- to 60-year-olds in the two UK populations compared with the others. SSRIs were prescribed more often than TCAs in all except the German population. In the majority of countries we observed an increasing trend of antidepressant prescribing over time. Two different methods identifying recorded indications yielded different ranges of proportions of patients recorded with the specific indication (15-57% and 39-69% for depression respectively). CONCLUSION: Despite applying uniform methods, variations in the prevalence of antidepressant prescribing were obvious in the different populations. Database characteristics and clinical factors may both explain these variations.

[Treatment of infected diabetic foot ulcers clinical effectiveness of a dressing of alginate and hydrocolloid, with silver fiber. Analysis of results of a series of cases]. / Tratamiento de úlceras infectadas de pie diabético.

INTRODUCTION: High levels of bacterial load have shown a deleterious influence on wound healing. Using antimicrobial dressings can control ulcers' bioburden. The aim of our study was to evaluate the improving of infected diabetic foot ulcers due an alginate's fiber and hydrocolloid silver dressing. MATERIAL AND METHODS: We analysed a case series of 6 patients with diabetic foot ulcers without peripheral vascular disease and diagnosed from critical colonization and/or local infection according the presence of inflammation clinical signs. Patients were treated for a minimum period of two weeks. We analysed the percentage reduction in ulcer area from the day of enrolment to antimicrobial dressing removal. RESULTS: The duration of treatment had a median of 5 weeks with a minimum of 2 weeks and up to 6. The median percentage of area reduction of the wounds was 47.7% (range: 0.5%-90%). The mean percentage reduction on the lesion was 58% from 2 weeks and 67.14% at 3 weeks. All patients had reduced significantly their size at 3 weeks from beginning of treatment (p < 0.05). CONCLUSION: The use of an alginate's fiber and hydrocolloid silver dressing promotes healing on diabetic foot ulcers with local infection, reducing the inflammatory clinical signs significantly over a period of three weeks.

Contribution of nursing students to clinical settings: A multi center cross sectional study.

AIMS: To describe the contribution of nursing students to clinical settings based on the perceptions of nurse preceptors and to examine whether certain characteristics of nurses' professional activity are associated with a positive perception of nursing students. BACKGROUND: Most clinical agencies receive many nursing students each year, who acquire clinical competencies under the guidance of a registered nurse preceptor. However, there is limited evidence of the contributions made by nursing students during clinical placements. METHODS: A multi-center cross-sectional study was carried out between June and December 2019. A convenience sample of Registered Nurses (n = 927) was recruited from four public hospitals in Spain. The Nursing Student Contributions to Clinical Settings' questionnaire was used. In addition, sociodemographic, work and teaching activity variables were collected. Multivariable logistic regression was used to determine the variables associated with positive student contributions. RESULTS: The nursing student contributions were deemed favorable by 70.7% of the nurse preceptors, mainly because the nursing students are future professionals who know the center, support the development of the nurses' teaching role and constitute a link between the health center and the university. Certain professional characteristics of the Registered Nurses were significantly associated with a positive perception of the contributions of nursing students: having daily coffee breaks (Odds ratio: 2.60; 95% Confidence interval:1.27-5.32), high levels of professional satisfaction (Odds ratio: 2.13; 95% Confidence interval:1.21-3.75) and work in medical-surgical units (Odds ratio: 1.62; 95% Confidence interval: 1.08-2.41). In contrast, nurses with greater work experience (≥ 30 years) (Odds ratio: 0.48; 95% Confidence interval: 0.27-0.85) and who worked at units where 10 or more students perform clinical practice (Odds ratio: 0.57; 95% Confidence interval: 0.36-0.90) were associated with a lower probability of positive perceptions. CONCLUSIONS: In Spain, the contributions made by nursing students to clinical settings are favorable, both for the nursing profession and for healthcare institutions. Their contributions are influenced by the professional characteristics of the Registered Nurses, as well as the environment and the teaching activity within the units.

MiR-146a polymorphism is associated with asthma but not with systemic lupus erythematosus and juvenile rheumatoid arthritis in Mexican patients.

Extensive research has shown that aberrant expression of microRNAs (miRNAs) plays an important role in innate and adaptive immune responses. The rs2910164 polymorphism has been identified as a functional variant, which affects the transcription and expression level of miR-146a and, thereby, contributes to the pathogenesis of several inflammatory and autoimmune diseases. To investigate whether the rs2910164 G/C polymorphism was associated with asthma, systemic lupus erythematosus (SLE) or juvenile rheumatoid arthritis (JRA), we performed an association study in a pediatric Mexican cohort. We included 979 pediatric patients (asthma: 402, SLE: 367 and JRA: 210) and 531 control subjects without inflammatory or immune diseases. Genotyping was performed using the 5' exonuclease technique. The genotype distribution of the rs2910164 polymorphism was in Hardy-Weinberg equilibrium in each group. No significant differences were detected in the distribution of this polymorphism between cases and controls (P = 0.108, 0.609 and 0.553 for subjects with asthma, JRA and SLE, respectively). However, stratification by gender showed a statistically significant difference between asthmatic and control females, where the C allele was significantly associated with protection to asthma (odds ratio = 0.694, 95% confidence interval 0.519-0.929, P = 0.0138). Our results provide evidence that rs2910164 may play a role in the susceptibility to childhood-onset asthma, but not SLE or JRA in Mexicans. Further association studies may contribute to determining the role of miR-146a single-nucleotide polymorphisms in immune-mediated diseases.

Neuropilin-2 regulates androgen-receptor transcriptional activity in advanced prostate cancer.

Aberrant transcriptional activity of androgen receptor (AR) is one of the dominant mechanisms for developing of castration-resistant prostate cancer (CRPC). Analyzing AR-transcriptional complex related to CRPC is therefore important towards understanding the mechanism of therapy resistance. While studying its mechanism, we observed that a transmembrane protein called neuropilin-2 (NRP2) plays a contributory role in forming a novel AR-transcriptional complex containing nuclear pore proteins. Using immunogold electron microscopy, high-resolution confocal microscopy, chromatin immunoprecipitation, proteomics, and other biochemical techniques, we delineated the molecular mechanism of how a specific splice variant of NRP2 becomes sumoylated upon ligand stimulation and translocates to the inner nuclear membrane. This splice variant of NRP2 then stabilizes the complex between AR and nuclear pore proteins to promote CRPC specific gene expression. Both full-length and splice variants of AR have been identified in this specific transcriptional complex. In vitro cell line-based assays indicated that depletion of NRP2 not only destabilizes the AR-nuclear pore protein interaction but also inhibits the transcriptional activities of AR. Using an in vivo bone metastasis model, we showed that the inhibition of NRP2 led to the sensitization of CRPC cells toward established anti-AR therapies such as enzalutamide. Overall, our finding emphasize the importance of combinatorial inhibition of NRP2 and AR as an effective therapeutic strategy against treatment refractory prostate cancer.

Prevention of chemotherapy-induced nausea and vomiting in the real-world setting in Spain.

PURPOSE: Proper monitoring and management of chemotherapy-induced nausea and vomiting (CINV) with antiemetics is crucial for cancer patients. This study aimed to evaluate the use of antiemetics for the treatment of highly emetogenic chemotherapy (HEC) including carboplatin in the real-world setting in Spain. METHODS: A representative panel of cancer specialists was asked to collect information about the antiemetic treatments provided to patients receiving chemotherapy. Records formed part of the Global Oncology Monitor© database (Ipsos Healthcare, London, UK). Chemotherapy data were extrapolated using Ipsos Healthcare's projection methodology. RESULTS: A total of 73 experts were finally included. Data from 9519 patients, estimated to be representative of 202,084 patients, were collected. HEC (and carboplatin-based chemotherapy) was administered to 73,118 (36%) patients, cisplatin-based therapy being the most frequent treatment (n = 34,649, 47.38%). Neurokinin-1 receptor antagonists (NK1RAs) alone or in combination were used as prophylaxis for CINV in 14,762 (20%) patients, while the combination of NK1RA with 5-hydroxytryptamine-3 receptor antagonist (5-HT3RAs) and dexamethasone as recommended by the international guidelines was used in 5849 (8%) patients only. No antiemetic prophylaxis was administered to 8.46% of the patients receiving HEC (n = 6189). Physicians classified cisplatin-, anthracycline-cyclophosphamide (AC-), and carboplatin-based regimens as HEC in 63%, 22% and 4% of the cases, respectively. CONCLUSIONS: The use of NK1RA-containing regimens for CINV prevention in patients treated with HEC was less than expected, suggesting poor adherence to international antiemetic guidelines.

Evaluation of patient quality care in Spain in prevention of nausea and vomiting induced by chemotherapy.

OBJECTIVE: To characterise current management of chemotherapy-induced nausea and vomiting in Spain, as well as professional adherence to antiemetic guidelines. MATERIALS AND METHODS: Retrospective observational study. A multicenter has been designed including 360 patient case files from 18 hospitals. The involvement of pharmacists and nurses was studied, and also indicators of structure, process, and selected outcomes previously recruited from antiemetic guidelines. RESULTS: We found 94.4% of hospitals used a written protocol for managing chemotherapy-induced nausea and vomiting and only 44.4% had educational programs for patients regarding this. Patients were prescribed antiemetic prophylactic treatment for delayed emesis in varying degree between highly and moderately emetogenic chemotherapy (77.8% and 58.9%, respectively). Dexamethasone was the most prescribed antiemetic drug for patients receiving highly and moderately emetogenic chemotherapy (98.3% and 90%, respectively), followed by ondansetron (68.9% and 95%, respectively). Nursing was more involved than pharmacy units in evaluating emetic risk factors in patients (64.7% vs 21.4%), and tracking symptom onset (88.2% vs 57.1%) and adherence to treatment (94.1% vs 28.6%). Pharmacy units were more involved than nursing in choosing the antiemetic treatment (78.6% vs 47%). CONCLUSIONS: Although antiemetic guidelines were used by all hospitals, there were differences in management of chemotherapy-induced nausea and vomiting. Increased education directed towards patients and oncology professionals is needed to improve adherence.

SEOM clinical guidelines for anaemia treatment in cancer patients (2020).

Anaemia is defined by the presence of haemoglobin (Hb) levels < 13 g/dL in men and 12 g/dL in women. Up to 39% of cancer patients present it at the time of diagnosis and up to 40% have iron deficiency. Anaemia causes fatigue, functional deterioration and a reduction in the quality of life; it has also been associated with a poorer response to anti-tumour treatment and lower survival. Basic diagnostic tests for anaemia are simple and should be a routine part of clinical practice. These guidelines review the available evidence on the use of different therapies for treating anaemia: erythropoiesis-stimulating agents, iron supplements, and transfusion of blood products.

[Rapid immune response against hepatitis B using an accelerated intradermal vaccination schedule]. / Respuesta inmune rápida contra la hepatitis B mediante esquema acelerado de vacunación intradérmica.

OBJECTIVE: To analyze the prescription of antiviral and antibiotic agents in children with upper airway infection (UAI) during Influenza H1N1 epidemic. METHODS: A cross-section study (01/04/2009 to 31/03/2010) was performed. We analyzed the antiviral and antibiotic agents' prescription and its relation with the presence of the triad of symptom of suspicion (migraine, fever and cough) and the cost for attention (medicines and screening test). RESULTS: 838 children were attendance for UAI, 40.3% with the suspicion triad. In 733 patients, the screening test were done with 155 positive results (120 had the triad). All patient with a positive result received oseltamivir. During the first five months of the epidemic, the medical prescriptions were: antibiotics 60-85%, 0-7% anti-viral and 20-30% symptomatic drugs. At the 6th at 8th months (peak of outbreak) antibiotics 35-70%, anti-virals 20-25% and 10-30% symptomatic drugs. At final months (9th to 11th) antimicrobials 65-80%, anti-virals 20-30% and symptomatic 0-10%. The cost for URI attention increased a 27%. CONCLUSIONS: Medical prescription changed during the epidemic, with an increased in the anti-virals, especially for patients with high suspicion for influenza and positive screening test.

Breakthrough cancer pain: review and calls to action to improve its management.

In this paper, we review the current state of breakthrough cancer pain (BTcP) management. BTcP is a heterogeneous condition and a global problem for cancer patients. It is often managed suboptimally, which results in a negative outcome for patients, healthcare providers, and healthcare systems. Several barriers to the appropriate management of BTcP have been identified. These include, among others, an incomplete definition of BTcP, poor training of healthcare providers and patients alike, a lack of a multidisciplinary approach and the absence of specific protocols and tools. We provide some actions to help physicians and patients improve their approach to BTcP, including specific training, the design of easy-to-use tools for BTcP identification and assessment (such as checklists and pocket-sized cards), individualized treatment, and the use of multidisciplinary teams.

Predictors of Diabetic Foot Reulceration beneath the Hallux.

AIMS: To evaluate the factors that predict reulceration beneath the hallux in people with a history of diabetic foot ulceration. METHODS: A prospective study conducted between January 2012 and December 2014 was performed in a diabetic foot unit to assess the risk factors associated with hallux reulceration. Sixty patients with diabetic neuropathy and a history of previous ulcer were consecutively included. Sociodemographic factors and comorbidities plus the biomechanical and radiographic factors were obtained. Follow-up on participants was conducted every month, and they wore offloading therapeutic footwear and custom-made insoles. Hallux reulceration during the follow-up period was assessed as the main outcome measure in the study. RESULTS: Patients were followed up during 29 (14.2-64.4) months. Twenty-nine patients (52%) developed a new ulceration: 9 patients (31%) in the hallux and 20 (69%) in other locations. Functional hallux limitus (p = 0.005, 95% CI (2.097-73.128), HR 12.384) and increased body mass index (p = 0.044, 95% CI (1.003-1.272), HR 1.129) were associated with the hallux ulceration-free survival time in the multivariate Cox model. CONCLUSIONS: Obesity and the presence of functional hallux limitus increase the probability of developing hallux reulceration in patients with diabetic neuropathy and a history of ulcers.

Role of NADPH oxidase and iNOS in vasoconstrictor responses of vessels from hypertensive and normotensive rats.

BACKGROUND AND PURPOSE: To analyse the influence of hypertension in the modulation induced by inducible NOS (iNOS)-derived NO and superoxide anion (O(2) (*-)) of vasoconstrictor responses and the sources of O(2) (*-) implicated. EXPERIMENTAL APPROACH: Vascular reactivity experiments were performed in segments of aorta from normotensive, Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR); protein and mRNA expressions were respectively measured by western blot and quantitative reverse transcription-polymerase chain reaction and O(2) (*-) production was evaluated by ethidium fluorescence. KEY RESULTS: The contractile responses to phenylephrine (1 nM-30 microM) and 5-hydroxytryptamine (0.1-100 microM) were greater in aortic segments from SHR than WKY. The selective iNOS inhibitor, 1400W (10 microM), increased the phenylephrine contraction only in WKY segments; however, iNOS protein and mRNA expressions were greater in aorta from SHR than WKY. Superoxide dismutase (SOD, 150 U ml(-1)) reduced phenylephrine and 5-hydroxytryptamine responses only in aorta from SHR; the NAD(P)H oxidase inhibitor apocynin (0.3 mM) decreased phenylephrine and 5-hydroxytryptamine responses more in vessels from SHR than WKY. Co-incubation with SOD plus 1400W potentiated the phenylephrine and 5-hydroxytryptamine responses more in segments from SHR than WKY. O(2) (*-) production was greater in aorta from SHR than WKY; apocynin abolished this difference. CONCLUSIONS AND IMPLICATIONS: Increased O(2) (*-) formation from NADP(H) oxidase in vessels from hypertensive rats contributes to the vasoconstrictor responses and counteract the increase of NO from iNOS and the consequent modulation of these responses.

BCR-ABL, ETV6-RUNX1 and E2A-PBX1: prevalence of the most common acute lymphoblastic leukemia fusion genes in Mexican patients.

This study was conducted to determine the frequency of the most common fusion genes in Mexican pediatric patients with acute lymphoblastic leukemia (ALL). Molecular analysis using RT-PCR was carried out in 53-blood samples: 52 patients with de novo ALL and one with relapsed ALL. The ETV6-RUNX1 fusion was found in 7 cases (13.5%), BCR-ABL fusion was detected in 2 cases (3.8%), and 6 patients (11.5%) expressed the chimeric gene E2A-PBX1. The prevalence of E2A-PBX1 is one of the highest that has been described thus far in childhood ALL. Furthermore, we detected both the BCR-ABL, and E2A-PBX1 fusion in the relapsed patient. With regards to the immunophenotype, ETV6-RUNX1 was expressed in both pre-B and T-cell cases, while the presence of E2A-PBX1 and BCR-ABL was associated with the pre-B ALL phenotype. The prevalence of E2A-PBX1 in Mexican pediatric cases supports the existence of ethnic differences in the frequency of molecular markers of ALL.

Study of paracetamol 1-g oral solution bioavailability.

The aim of this work was to assess paracetamol bioavailability after administering 1 g in oral solution. Eighteen healthy volunteers were selected for this open-label study. A total of 15.4 ml of Gelocatil Oral Solution (Laboratorios Gelos, S.L.), corresponding to 1 g of paracetamol, were administered to fasting subjects. Blood samples were collected at 0 min, 10 min, 20 min, 30 min, 45 min, 1 h, 1.5 h, 2 h, 3 h, 4 h, 6 h, 8 h, 10 h and 12 h. Paracetamol plasma concentrations were determined by reverse-phase high-performance liquid chromatography. The study was conducted without deviations from protocol. Pharmacokinetic data from 18 subjects were allowed for estimating fast and high-paracetamol bioavailability: t(max) 20 min (10-45) [median (range)], C(max) 24. 3 mg/l (6.5) [mean (standard deviation)], AUC(0-t) 64.0 mg h/l (16.1) and AUC(0-00) 68.1 mg h/l (17.9). These results are comparable to those described for Gelocatil Oral Solution given at a 650 mg dose and for immediate release Gelocatil 650 mg tablets. Absorption speed was very fast, similar to that described for other oral-solution formulations, which provides an immediate onset of pain and fever relief. The results of this study show suitable bioavailability for 1 g Gelocatil Oral Solution, with fast-absorption speed that provides an immediate onset of pain and fever relief.

An epidemiological study of the perception of asthenia by oncologists in cancer patients: POA study.

INTRODUCTION: Despite the high prevalence of asthenia in cancer patients, around 50-75%, and its impact on quality of life, it continues to be a difficult symptom to assess and manage. This study defines the extent of perception and diagnosis of asthenia associated with cancer among Spanish oncologists. METHODS: A descriptive, observational study conducted in Spain based on a five-part structured questionnaire available to participants through a private website. RESULTS: The 100 oncologists surveyed, most in the public healthcare setting, diagnose asthenia in 58-70% of cases. They consider old age (56.5%) and advanced-stage disease (94.2%) as factors associated with the occurrence of asthenia, which is also common in, particularly, tumours, such as pancreatic cancer (30.4%), and some therapies, notably chemotherapy alone (67%) or combined with radiotherapy (96%). Despite its adequate detection, physicians rarely ask their patients about asthenia, use instruments for its evaluation or assess its impact on quality of life. Likewise, only 40% of all patients are treated, although therapeutic intervention, a multidisciplinary approach combining drug and non-drug treatments and managing a variety of causative factors, can be considered adequate. Finally, 91.5% of those surveyed do not have action guidelines for asthenia in their hospitals. CONCLUSIONS: Even when asthenia is widely diagnosed in cancer patients in Spain, there is a laxity in its assessment and treatment. Increased awareness among healthcare professionals of its impact and relevance is therefore required, as well as adequate protocols for its systematic detection and management within the routine assessment and treatment of cancer patients.

[Is there a shift in the epidemiology of hepatitis A in Mexican children?]. / Existe transición en el patrón endémico de la hepatitis A en población infantil mexicana?

INTRODUCTION: Twenty years ago, prevalence of Hepatitis A in Mexican children was 90%. OBJECTIVE: To describe a shift in the prevalence of Hepatitis A virus (HAV) infection and to demonstrate an increment in the age at the first contact with HAV, in a sample of Mexican children. MATERIAL AND METHODS: Reports of antiviral serologic studies collected from 1991 to 2005 from patients attending a pediatric hospital, were reviewed, and those with IgM anti-HAV positive in serum were selected. Age at the moment of acute infection was analyzed. Additionally, a serological survey searching IgG anti-HAV was made in a group of HAV unvaccinated children. RESULTS: From 1708 determinations of IgM, 221 were positive (13%). According to the year of report, five groups were constituted. Mean age by group was: 1991-1993 of 6.4 years, 1994-1996 of 8.0, 1997-1999 of 8.4, 2000-2002 of 8.0 and from 2003-2005 of 10.1 years. In a cohort of 259 unvaccinated children (mean of age 8.59 years), IgG antibodies were detected in 51%. CONCLUSION: In the infantile population studied a Hepatitis A epidemiology shift is suggested.