Acinetobacter baumannii infections in a tertiary care hospital in Mexico over the past 13 years.

BACKGROUND: Acinetobacter baumannii has evolved from an opportunistic pathogen into a common and persistent nosocomial bacterium capable of causing severe infections during endemic and epidemic periods. METHODS: The study period extended from January 1999 to December 2011 and involved patients hospitalized at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, Jalisco, Mexico. From each patient, a single isolate was obtained, and a total of 3,680 unique isolates were collected. Susceptibility tests were performed according to the guidelines of the Clinical and Laboratory Standards Institute. RESULTS: A. baumannii has disseminated throughout the Hospital Civil de Guadalajara, Fray Antonio Alcalde, since 1999. A. baumannii isolates obtained from patients treated in the adult intensive care unit represent the majority of the isolates that have been collected. In addition, A. baumannii was isolated from the adult neurosurgical ward and the adult internal medicine ward, and these isolates were frequently obtained from secretions. A persistent decrease in the susceptibility of A. baumannii isolates to meropenem (92% in 1999 to 12% in 2011), imipenem and amikacin has been observed. CONCLUSIONS: A. baumannii became an endemic nosocomial pathogen during the study period at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, and has exhibited a persistent decrease in susceptibility to all categories of antimicrobial agents over the past 13 years.

Mexican anthropometric percentiles for ages 10-18.

OBJECTIVE: To elaborate Mexican growth charts based on international methodology. DESIGN: Data were obtained from the Mexican National Health Survey. The survey was stratified and probabilistic representative of all the country. SETTING: Nationwide open population living in urban and rural areas. SUBJECTS: Boys (8545) and girls (9983) from 10 to 18 years participating in the survey. METHODS: Age, weight and height were recorded. Empirical percentiles were calculated and smoothed. Smoothed curves were approximated using least-mean square estimation. RESULTS: Tables and figures for percentile values of weight, height and body mass index (BMI) for age, as well as percentile values of weight and BMI for height for both genders are presented. Regarding 50th BMI for age percentiles, Mexicans had higher levels than the Americans in the Centers for Disease Control and Prevention growth charts; Mexicans were lower but had similar weights than the Americans. Owing to the high BMI, the percentile corresponding to an overweight level (25 kg/m(2)) at 18 years was 74.5 in boys and 72.5 in girls, whereas obesity level (30 kg/m(2)) at 18 years was 97.3 and 97.4 in boys and girls, respectively. CONCLUSIONS: The present growth charts are snapshots of a Mexican population. Because of the high median BMI compared to US and World Health Organization standards, we must be cautious in establishing an upper normal cutoff for clinical normality, not merely selecting the 85th and 95th percentiles as equivalents of overweight and obesity, respectively. Therefore, we proposed percentiles 74.5 in boys and 72.5 in girls as the action points of overweight as they are the percentiles corresponding to BMI 25 kg/m(2) at 18 years. SPONSORSHIP: The survey was supported by the Mexican Minister of Health. Statistical analyses were sponsored by Dr Del-Rio-Navarro.

Complete Genome Sequence of Human Coronavirus OC43 Isolated from Mexico.

We report the complete genome sequence of the first Mexican human coronavirus (HCoV) OC43, obtained by new-generation sequencing and a metagenomic approach, isolated from a child hospitalized with pneumonia. The genome is closely related to the other OC43 genome sequences available, ranging from 99.8% to 98.2% nucleotide sequence identity.

Survey of drug resistance of Mycobacterium tuberculosis in 3 Mexican states, 1997.

BACKGROUND: Drug resistance threatens global tuberculosis (TB) control efforts. Population-based estimates of drug resistance are needed to develop strategies for controlling drug-resistant TB in Mexico. OBJECTIVE: To obtain population-based data on Mycobacterium tuberculosis drug resistance in Mexico. METHODS: To obtain drug resistance data, we conducted a population-based study of TB cases in the states of Baja California, Sinaloa, and Oaxaca, Mexico. We performed cultures and drug susceptibility testing on M tuberculosis isolates from patients with newly diagnosed, smear-positive TB from April 1 to October 31, 1997. RESULTS: Mycobacterium tuberculosis was isolated from 460 (75%) of the 614 patients. Levels of resistance in new and retreatment TB cases to 1 or more of the 3 current first-line drugs used in Mexico (isoniazid, rifampin, and pyrazinamide) were 12.9% and 50.5%, respectively; the corresponding levels of multi-drug-resistant TB were 2.4% and 22.4%. Retreatment cases were significantly more likely than new cases to have isolates resistant to 1 or more of the 3 first-line drugs (relative risk [RR], 3.9; 95% confidence interval [CI], 2.8-5.5), to have isoniazid resistance (RR, 3.6; 95% CI, 2.5-5.2), and to have multi-drug-resistant TB (RR, 9.4; 95% CI, 4.3-20.2). CONCLUSIONS: This population-based study of M tuberculosis demonstrates moderately high levels of drug resistance. Important issues to consider in the national strategy to prevent M tuberculosis resistance in Mexico include consideration of the most appropriate initial therapy in patients with TB, the treatment of patients with multiple drug resistance, and surveillance or periodic surveys of resistance among new TB patients to monitor drug resistance trends.

An outbreak of Cryptosporidium diarrhea in a pediatric hospital.

PIP: Physicians investigated a nosocomial diarrhea outbreak among 11 2 year old undernourished children in the nutrition service of the pediatric teaching hospital, Hospital Infantile, in Mexico City, Mexico in April 1988. Health practitioners took at least 2 stool samples from each ill child to be analyzed for Cryptosporidium oocysts. The attack rate stood st 82%. The hospital admitted a malnourished child with chronic diarrhea and pneumonia on March 22. Laboratory tests revealed that he had many Cryptosporidium oocysts and was positive for HIV. Hospital staff did not isolate him. He died on May 9 of Escherichia coli and Candida septicemia. The outbreak ended 1 week later. Laboratory tests detected Cryptosporidium oocysts in 9 cases all of whom were 3-13 months old. Further the symptoms (mean duration 14 days, fever [mean peak 38.6 degrees Celsius, and vomiting] matched those of other reported Cryptosporidium diarrhea outbreaks. The epidemic curve suggested a common source of the outbreak. Since the infants received intravenous feedings or sterilized formula, food and water could not have been the source. The physicians believed the AIDS case was that source. Direct person to person transmission was probably not responsible since each infant had his/her own separate crib. Even though the physicians could not conclusively identify the vehicle of transmission, it was most likely the hands of hospitals staff either directly by touching the infants or by contaminating the nasogastric tubes. After the outbreak, the physicians observed that only 30% of medical personnel indeed washed their hands before caring for an infant. 4 previous studies on nosocomial Cryptosporidium diarrhea outbreaks also reported the source case as immunodeficient, but these studies only included adults.^ieng

Improved serological response to human diploid cell rabies vaccine when given simultaneously with antirabies hyperimmune globulin.

BACKGROUND: The prevention of rabies in Mexico continues to be an important goal for the health sector. Although the prevalence of this disease continues to fall, between 1990 and 1995 a total of 238 cases were registered (an average of 40 cases annually), with a mean annual incidence of 0.04 cases per 100,000 inhabitants and a mortality of almost 100%, so that it is important to rely on highly effective vaccines with few side effects. The objective of this work was to evaluate seroconversion and tolerance to the human diploid cell antirabies vaccine administered to individuals with a history of exposure to rabies, to compare these results with those reported in the literature for the Fuenzalida vaccine, a rabies vaccine produced in the brain tissue of suckling mice, and to find the role antirabies hyperimmune gamma globulin plays in the concentration of post-vaccination antibody concentrations. METHODS: An analytical transverse study was carried out in 40 children and adults with a history of rabies exposure who were given a complete, five-dose intramuscular schedule of the human diploid cell rabies vaccine. Subjects were followed daily, and local and systemic signs and symptoms were recorded. Two blood samples (at baseline and at the end of the vaccination schedule) were taken and antibody titers against rabies glycoprotein, using the ELISA technique, were measured. RESULTS: Adverse side effects produced by the human diploid cell antirabies vaccine, such as frequency of pain, erythema, itching, and regional adenopathy were fewer than those reported in the literature for the Fuenzalida vaccine (p < 0.05), and of induration and local pain (p < 0.05) in relation to the latter vaccine. All patients seroconverted, producing geometric mean antibody titers of 6.22 IU/mL, an arithmetic mean titer of 9.66 IU/mL with a SD of 9.1 IU/mL. The level of tolerance to the diploid cell vaccine was good and its adverse effects were minimal and fewer than those reported for the Fuenzalida rabies vaccine. Patients receiving the diploid cell vaccine plus antirabies hyperimmune gamma globulin developed higher antibody titers (measured by ELISA test) at the end of the vaccination schedule than those only receiving the vaccine. CONCLUSIONS: These results are important in order to achieve an adequate and opportune level of protection provided by prophylactic vaccines to patients with exposure to rabies.

Macrophage colony-stimulating factor enhances the respiratory burst of human monocytes in response to Entamoeba histolytica.

Mononuclear phagocytes (MP) are probably the most capable effector cells of the body in the defense against virulent strains of E. histolytica. Killing of E. histolytica by MP appears to involve both oxidative and non-oxidative mechanisms. Thus, in this study we have investigated whether trophozoites of an axenic virulent strain E. histolytica HM1:IMSS (EH) were capable of eliciting an oxidative response in pure populations of freshly isolated human monocytes. Using a luminol-enhanced chemiluminescence assay we demonstrate that these cells produce a strong respiratory burst when challenged with live amebas over a wide range of MP:EH ratios. Furthermore, pre-incubation of monocytes with recombinant Macrophage Colony Stimulating Factor (M-CSF) could further increase the oxidative metabolism of MP in response to E. histolytica. Our results indicate that, in contrast to what occurs with polymorphonuclear leukocytes, the interaction of E. histolytica with MP leads to the production of reactive oxygen intermediates by this cells. The enhancement of this potent microbicidal mechanism by inflammatory cytokines may further increase the amebicidal capacity of human mononuclear phagocytes.

Opsonic capacity of a hyperimmune serum against outer membrane proteins of Klebsiella pneumoniae.

The opsonic capacity of a hyperimmune rabbit serum against a porin-rich outer membrane protein preparation of a strain of K. pneumoniae was evaluated. By immunoblot, the antiserum recognized mainly the porins from an outer membrane protein preparation. Using an ELISA, the titer of anti-porin antibodies was determined. Through a chemiluminescence assay, the increase in the respiratory burst of murine hyperimmune serum was recorded. These data correlate with the results of the microbicidal assays and with the electron microscopy preparations obtained where a great number of bacteria were seen within the macrophages. The in vitro data show that there is a greater bacterial killing when the macrophage is infected with bacteria opsonized with the hyperimmune serum.

[Advances in the molecular diagnosis of infectious and parasitic diseases]. / Avances en el diagnóstico molecular de las enfermedades infecciosas y parasitarias.

During the last decade molecular diagnostic techniques have moved from the research laboratory into the clinical microbiology laboratory. The application of molecular biology for the diagnosis of infections and parasitic diseases by the detection of nucleic acids has steadily grown, and it is very probably that, while they may not displace the traditional diagnostic laboratory, they will be common place in the not to distant future. A detailed description of the principal molecular diagnostic techniques that are currently being used or that have a potential use for the diagnosis, evaluation of disease progression or response to therapy of selected infectious and parasitic diseases, is presented. Emphasis is placed on the rational use of these techniques in regional reference laboratories or highly specialized hospitals; the importance of selecting and implanting those diagnostic techniques with the highest cost-benefit ratio; and finally, the need to train human resources which are highly qualified in the theory and practice of molecular biology.

[Phosphatidylcholine induces an increase in the production of interleukin-6 and improves survival of rats with neonatal sepsis caused by Klebsiella pneumoniae]. / La fosfatidilcolina induce un aumento en la producción de interleucina-6 y mejora la sobrevida de ratas con sepsis neonatal por Klebsiella pneumoniae.

Infections by gram-negative bacteria are one of the major causes of death in newborns. Bacterial clearance is deficient in septic neonates, which seems to increase their susceptibility to infections. In this study, we observed a significant improvement in clearance of Klebsiella pneumoniae in newborn wistar rats inoculated by intraperitoneal via with 800 mg k soybean phosphatidylcholine (PC), compared to the control group injected with PBS (p 0.05). The overall survival rate was improved (p 0.05) and the white blood cell counts showed a greater leukocytosis and neutrophilia during the peak of bacteremia in the PC treated animals. Circulating levels of interleukin-6 were greater in the PC group, which developed an intense splenic hematopoiesis of the granulocyte (p 0.05) and megakariocyte series (p 0.01). No significant changes were observed in bone marrow granulocyte deposits in both study groups. The improvement in survival rate, the changes in leukocyte counts and the splenic hematopoiesis may be associated with the increased production of IL-6. These results suggest that IL-6 plays a role in the protection mechanism induced by PC in this experimental model of newborn septicemia. PC seems to be an immunomodulator of the acute response to gram-negative bacterial infection.

[FARMAC: a program designed for monitoring the prescription of antimicrobials in hospitals]. / FARMAC: programa diseñado para vigilar la prescripción de antimicrobianos en hospitales.

INTRODUCTION: The use of computer programs for monitoring the prescription of antimicrobial agents in hospitals is of paramount importance in the incorporation of electronic databases developed and analyzed by several hospital committees, including the following: infection control; pharmacy; morbidity and mortality; and quality assurance committees, as well as other key areas or departments such as pathology, pharmacy, microbiology, radiology, or hospital administration. OBJECTIVE: To describe the development and use of an "information system" employed for monitoring the prescription of antimicrobial agents in hospitalized patients. MATERIAL AND METHODS: A printed format was developed in order for physicians to ask for authorization for the use of restricted antimicrobial agents (i.e. third-generation cephalosporins and other newly introduced beta lactams, fluoroquinolones, antifungals, antivirals, etc). A computer program, "FARMAC", was designed using the Dbase IV program. FARMAC contemplates the presentation on a screen of a main menu allowing for the use of several options: admissions; antibiotic changes; consultations; discharges; hospital transfers; reports, and distribution. The reports are generated from the menu and appear on the screen or are printed in representative tables and figures. Generally speaking, the system processes information on the use of antimicrobial agents, files information, allows for consultation, of the information and generates reports quickly and efficiently. RESULTS: The presentations were defined on screen, taking into account the space needed in order to avoid an inadequate distribution of the messages, therefore obtaining an optimal image. A database was created defining the necessary fields for storing information with reference to patients and usage patterns of restricted antimicrobial agents. DISCUSSION: The development of an information and surveillance system on the prescription of antibiotics allows for consulting updated information, making the data analysis easier for decision making. Its use will allow for surveying tendencies and usage patterns of controlled and non-controlled antimicrobial agents.

[Surveillance and the costs related to the prescription of antimicrobials in a pediatric hospital]. / Vigilancia y costos relacionados con la prescripción de antimicrobianos en un hospital pediátrico.

INTRODUCTION: Important considerations in the selection of an antimicrobial agent include the indications for its prescription, its efficacy, toxicity and cost. However, is has been observed that up to 50% of these prescriptions are inappropriate. OBJECTIVE: To evaluate the utilization patterns and costs of restricted antimicrobial agents requiring authorization of the infectious diseases service for their prescription, in a tertiary care pediatric hospital through the use of a computer software antimicrobial use surveillance program designed by the investigators. MATERIAL AND METHODS: A one-year longitudinal descriptive and prolective survey was conducted in all patients requiring antimicrobial therapy during their hospitalization. Information on the prescription and costs of antimicrobial agents was recorded from both the medical chart and pharmacy registers. RESULTS: A total of 748 patients were prescribed at least one restricted antimicrobial agent, corresponding to 9.6% of the total number of patients hospitalized and 63.4% of the antibiotic expenditures during the study. CONCLUSIONS: Hospital surveillance of antimicrobial prescription is useful for detecting antimicrobial prescription patterns and costs. These types of studies are inexpensive and of easy access when a computerized register is available in the pharmacy.

[The usefulness of the polymerase chain reaction (PCR) in research and clinical diagnosis in pediatrics]. / Utilidad de la reacción en cadena con polimerasa (PCR) en la investigación y el diagnóstico clinico en pediatría.

Recent advances in molecular biology for the first time make possible the widespread application of this science for the diagnosis and clinical investigation of pediatric disease. One very important discovery has been the development of the polymerase chain reaction. This technique allows for the exponential amplification of specific DNA sequences producing quantities sufficient for the molecular diagnosis of a wide variety of diseases. We review some of the fundamental aspects of this technique as well as some of its most promising applications in the field of pediatrics.

[Factors influencing the immunization of children in the outpatient clinic of a pediatric hospital]. / Factores que influyen en la inmunización de los niños en la consulta externa de un hospital pediátrico.

In 1991 a study conducted at the Hospital Infantil de Mexico in Mexico City, as a project of the MCH IPHI Program at the Center for Population and Family Health, Columbia University, New York. The purpose was to investigate health professional's knowledge, perceptions of barriers and actions to promote immunization. Knowledge, perceptions of barriers and actions (KPA) surveys were administered to 101 residents and 104 nurses. Using SPSS/PC analysis of health professionals (KPA) surveys demonstrate no correlation between their knowledge, perceptions of barriers to immunization and actions undertaken (P greater than 0.05). Recommendations made to the Hospital Infantil de Mexico include: the review of the immunization card on a regular basis, health education programs on immunization at the community and health professionals level, and interpersonal and mass communication.

[The prevalence of antibodies against Giardia lamblia in umbilical cord serum and in maternal peripheral blood]. / Prevalencia de anticuerpos contra Giardia lamblia en suero de cordón umbilical y en sangre periférica materna.

Using an immunoenzymatic assay (ELISA), 40 serum samples from the peripheral blood of women in labor and serum from the umbilical cord of their offspring were analyzed in order to detect the prevalence of antibodies against Giardia lamblia. The results show that 12.5% of the maternal serum samples and 15.0% of those from the umbilical cord had optical density values comparable to those positive for G. lamblia used in the assay. This suggests that important concentrations of maternal IgG antibodies for the parasite are transferred through the placenta. The role that these antibodies play in the neonatal protection is still to be determined.

[HIV infection in Mexican children]. / Infección por VIH en niños mexicanos.

OBJECTIVE: To review the experience of the Immunodeficiency Clinic of the Department of Infectious Diseases at Hospital Infantile de México "Federico Gómez", in the management of children with HIV infection and AIDS. MATERIAL AND METHODS: the medical records of 130 patients with a clinical and laboratory diagnosis of HIV/AIDS seen between September 1985 and June 1994 were reviewed. Data was obtained regarding diagnosis, epidemiological risk factors, clinical features, types and numbers of bacterial and opportunistic infections, malignancies, hospitalizations, general and specific treatment and outcome. The diagnosis followed CDC guidelines and was established in all 130 patients serologically with ELISA and Western Blot. In infants < 18 months, diagnosis was made by detection of p24 and/or viral culture in two separate occasions. RESULTS: Data from 130 subjects was obtained; 74 were male and 56 female for a M:F ratio of 1.3:1. With regards to mode of transmission, 62.3% was vertical, 20.8% post transfusion, 8.5% hemophiliacs (the latter two males were cases before occurred 1987), 6.2% sexual and 2.2% unknown. With regards to additional risk factors, in 35 cases the parents were heterosexual, in 18 one parent had a history of transfusion, and in eight the father was bisexual. According to the CDC classification; 16 had indeterminate infection or PO; nine were asymptomatic or P1; and 105 were symptomatic or P2. Eighty two patients had nonspecific findings, 60 had neurologic manifestations, 18 had lymphocytic interstitial pneumonia and four had secondary malignancies. It was possible to document 296 episodes of secondary infections: 154 bacterial, 58 opportunistic, and 84 with other pathogens. CONCLUSIONS: in Mexico, as in other Western countries, vertical transmission has become the dominant form of acquiring HIV infection in children, reflecting a change in the epidemiology of infection in women of child bearing age. Moreover, since IV drug use is a very limited phenomenon in Mexico, heterosexual transmission is the major form of transmission in women.