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J Sifuentes-Osornio

Publications and source records attributed to J Sifuentes-Osornio.

At least 19 recordsLinked to original sources
PubMed2006

Gender differentials of pulmonary tuberculosis transmission and reactivation in an endemic area.

BACKGROUND: In most low income countries there are twice as many cases of tuberculosis (TB) reported among men than among women, a difference commonly attributed to biological and epidemiological characteristics as well as socioeconomic and cultural barriers in access to health care. The World Health Organization has encouraged gender specific comparisons in TB rates to determine whether women with TB are less likely than men with TB to be diagnosed, reported, and treated. A study was undertaken to identify gender based differences in patients with pulmonary TB and to use this information to improve TB control efforts. METHODS: Individuals with a cough for more than 2 weeks in southern Mexico were screened from March 1995 to April 2003. Clinical and mycobacteriological information (isolation, identification, drug susceptibility testing and IS6110 based genotyping, and spoligotyping) was collected from those with bacteriologically confirmed pulmonary TB. Patients were treated in accordance with official norms and followed to ascertain treatment outcome, retreatment, and vital status. RESULTS: 623 patients with pulmonary TB were enrolled. The male:female incidence rate ratio for overall, reactivated, and recently transmitted disease was 1.58 (95% CI 1.34 to 1.86), 1.64 (95% CI 1.36 to 1.98), and 1.41 (95% CI 1.01 to 1.96), respectively. Men were more likely than women to default from treatment (adjusted OR 3.30, 95% CI 1.46 to 7.43), to be retreated (hazard ratio (HR) 3.15, 95% CI 1.38 to 7.22), and to die from TB (HR 2.23, 95% CI 1.25 to 3.99). CONCLUSIONS: Higher rates of transmitted and reactivated disease and poorer treatment outcomes among men are indicators of gender differentials in the diagnosis and treatment of pulmonary TB, and suggest specific strategies in endemic settings.

Endemic Diseases↗
PubMed2003

Antibacterial resistance of community-acquired respiratory tract pathogens recovered from patients in Latin America: results from the PROTEKT surveillance study (1999-2000).

PROTEKT (Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin) is a global surveillance study established in 1999 to monitor antibacterial resistance of respiratory tract organisms. Thirteen centers from Argentina, Brazil and Mexico participated during 1999-2000; they collected 1806 isolates (Streptococcus pneumoniae 518, Haemophilus influenzae 520, Moraxella catarrhalis 140, Staphylococcus aureus 351, S. pyogenes 277). Overall, 218 (42.1%) of the S. pneumoniae isolates had reduced susceptibility to penicillin, 79 (15.3%) were penicillin-resistant and 79 (15.3%) were erythromycin-resistant. Mexico had the highest prevalence of penicillin (76.5%) and erythromycin (31.2%) resistance. Of 77 erythromycin-resistant S. pneumoniae tested for resistance genotype, 43 possessed mef(A), 33 possessed erm(B) and 1 possessed both erm(B) and mef(A) mechanism. All S. pneumoniae isolates were fully susceptible to telithromycin, linezolid, teicoplanin and vancomycin. Among H. influenzae isolates, 88 (16.9%) produced beta-lactamase, ranging from 11% (Brazil) to 24.5% (Mexico). Among M. catarrhalis isolates, 138 (98.6%) produced beta-lactamase. Twenty-four (8.7%) of the S. pyogenes isolates were erythromycin-resistant; resistance being attributable to mefA (n=18), ermTR (n=5) and ermB (n=1). All H. influenzae, M. catarrhalis and S. pyogenes were fully susceptible to telithromycin. Methicillin resistance was found in 26.5% of the S. aureus isolates (Argentina 15%; Mexico 20%; Brazil 31.3%). Telithromycin was effective against 97.7% of methicillin-susceptible isolates. PROTEKT confirms that antibacterial resistance is an emerging problem in Latin America. The previously reported high levels of pneumococcal resistance to the beta-lactam and macrolides were exceeded. New agents that do not induce resistance or that exert low selective pressure, e.g. telithromycin, are essential to safeguard future antibacterial efficacy.

Anti-Bacterial Agents↗
PubMed2002

Purified protein derivative reaction in systemic lupus erythematosus patients. Indirect study of cellular immunity.

Cutaneous anergy in SLE patients results from disease activity and/or immunosuppressive treatment (IT). The aim of this study was to evaluate purified protein derivative (PPD) reaction in SLE patients. A total of 145 patients and 20 controls were studied. Five units of PPD were applied on day 0, and skin reaction was measured after 3 (PPD1) and 6 (PPD2) days. A booster was applied (day 14), and the reaction was measured after 3 (PPD3) and 6 (PPD4) days. Non-parametric ANOVA test and unpaired Student's t-test were performed. Forty patients (group I) were inactive (MexSLEDAI < 3), receiving no IT (at least 3 months previous to the PPD test); 39 (group II) were inactive receiving IT; 24 (group III) were active without IT, and 42 (group IV) were active with IT. Active patients had lower PPD1 (group III, 1.4 +/- 0.9; group IV, 0.6 +/- 0.5) than inactive patients (group I, 8.4 +/- 2.3; group II, 5.1 +/- 1.9) and than controls (9.4 +/- 3; P < or = 0.001). Group IV had lower delayed response (PPD2 = 0.3 +/- 0.3) than inactive groups (group I, 2.6 +/- 0.9; group II, 3.1 +/- 0.8) and than controls (7.9 +/- 2.5; P < or = 0.001). Group III had lower delayed reaction (PPD2 = 1.2 +/- 0.8) than controls (P < or = 0.001). Active SLE patients, receiving or not receiving IT, had lower skin response to PPD than inactive patients and controls.

Adult↗
PubMed2001

Luciferase reporter mycobacteriophages for detection, identification, and antibiotic susceptibility testing of Mycobacterium tuberculosis in Mexico.

The utility of luciferase reporter mycobacteriophages (LRPs) for detection, identification, and antibiotic susceptibility testing of Mycobacterium tuberculosis was prospectively evaluated in a clinical microbiology laboratory in Mexico City, Mexico. Five hundred twenty-three consecutive sputum samples submitted to the laboratory during a 5-month period were included in this study. These specimens were cultivated in Middlebrook 7H9 (MADC), MGIT, and Löwenstein-Jensen (LJ) media. Of the 71 mycobacterial isolates recovered with any of the three media, 76% were detected with the LRPs, 97% were detected with the MGIT 960 method, and 90% were detected with LJ medium. When contaminated specimens were excluded from the analysis, the LRPs detected 92% (54 of 59) of the cultures. The median time to detection of bacteria was 7 days with both the LRPs and the MGIT 960 method. LRP detection of growth in the presence of p-nitro-alpha-acetylamino-beta-hydroxypropiophenone (NAP) was used for selective identification of M. tuberculosis complex (MTC) and compared to identification with BACTEC 460. Using the LRP NAP test, 47 (94%) out of 50 isolates were correctly identified as tuberculosis complex. The accuracy and speed of LRP antibiotic susceptibility testing with rifampin, streptomycin, isoniazid, and ethambutol were compared to those of the BACTEC 460 method, and discrepant results were checked by the conventional proportion method. In total, 50 MTC isolates were tested. The overall agreement between the LRP and BACTEC 460 results was 98.5%. The median LRP-based susceptibility turnaround time was 2 days (range, 2 to 4 days) compared to 10.5 days (range, 7 to 16 days) by the BACTEC 460 method. Phage resistance was not detected in any of the 243 MTC isolates tested. Mycobacteriophage-based approaches to tuberculosis diagnostics can be implemented in clinical laboratories with sensitivity, specificity, and rapidity that compare favorably with those of the MGIT 960 and BACTEC 460 methods. The phages currently provide the fastest phenotypic assay for susceptibility testing.

Antitubercular Agents↗
PubMed2000

Clinical consequences and transmissibility of drug-resistant tuberculosis in southern Mexico.

BACKGROUND: Consequences of drug-resistant tuberculosis (TB) in developing countries using directly observed treatment, short-course (DOTS), are not well defined. OBJECTIVE: To determine the impact of drug resistance on clinical outcome and transmission of TB under programmatic conditions. PATIENTS AND METHODS: A prospective cohort and molecular epidemiologic study was conducted in southern Mexico. Between March 1995 and February 1998 all patients with persistent cough whose sputa had acid-fast bacilli (AFB) underwent clinical and mycobacteriologic evaluation (species identification, drug susceptibility testing, and IS6110-based genotyping). Treatment was provided in accordance with Mexico's National Tuberculosis Program. Clinical and microbiologic outcomes and molecular epidemiologically defined transmission were measured. RESULTS: Mycobacterium tuberculosis was isolated from 238 of the 284 AFB smear-positive persons. The overall rate of resistance was 28.4% (new, 20.7%; retreated, 54.7%), and 10.8% (new, 3.3%; retreated, 35.8%) had multi-drug-resistant TB (ie, resistance to isoniazid and rifampin). After treatment, 75% (new, 81.0%; retreated, 52.8%) were cured, 8% (new, 7.8%; retreated, 7.5%) abandoned therapy, 9% (new, 3.9%; retreated, 28.3%) had treatment failure, and 4% (new, 3.3%; retreated, 7.5%) died. Another 2% of patients relapsed, and 9% died during a median of 24.4 months of follow-up. Drug-resistance was a strong independent risk factor for treatment failure. Being infected with multi-drug-resistant TB was the only factor associated with a decreased likelihood of being in a restriction fragment length polymorphism cluster. CONCLUSIONS: Despite the use of DOTS, patients with drug-resistant TB had a dramatically increased probability of treatment failure and death. Although multi-drug-resistant TB may have a decreased propensity to spread and cause disease, it has a profoundly negative impact on TB control.

Adult↗
PubMed2000

Bloodborne viral infections in patients attending an emergency room in Mexico City: estimate of seroconversion probability in healthcare workers after an occupational exposure.

The frequency of hepatitis C (HCV), hepatitis B (HBV), human immunodeficiency virus (HIV), and human T-cell lymphotropic virus (HTLV) I/II was determined in the emergency room of a teaching hospital. Of 909 patients, 19% had at least one infection; 7.8% had HCV, 6.9% HBV, 3.3% HIV, and 2.8% HTLV I/II. The probability that a healthcare worker would have an accident with an infected patient and seroconvert was 4.99 to 24.9 per 100,000 venipunctures for HBV, 5.6 to 8.4 for HCV, and 0.12-0.16 for HIV in our emergency room.

Adolescent↗
PubMed2000

Mycobacterium tuberculosis drug resistance in a suburban community in southern Mexico.

OBJECTIVE: To determine the impact of drug resistance (DR) on the clinical outcome and transmission of tuberculosis under programmatic conditions. METHODS: Prospective cohort and molecular epidemiologic study in the Orizaba Health Jurisdiction of Mexico. Between March 1995 and July 1999, chronic coughers with positive acid-fast bacilli (AFB) detected in sputum smear underwent clinical and mycobacteriologic evaluation (species identification, drug susceptibility testing and IS6110-based genotyping). Treatment was provided in accordance with official norms. RESULTS: Mycobacterium tuberculosis was isolated from 326/387 AFB-positive cases. The rate of DR was 24.2% and that of multidrug resistance (MDR, defined as resistance to both isoniazid and rifampin at least) was 7.7%; 78% were cured, 8% abandoned treatment, 6% failed treatment, and 5% died. An additional 13.5% received retreatment and 8.9% died during a median 28.6 months of follow up. Factors associated with DR by multivariate analysis were chronicity of tuberculosis (OR 4.8, 95%CI 2.7-8.4, P < 0.001), age >40 years (OR 1.9, 95%CI 1.1-3.2, P = 0.02) and indigenous origin (OR 0.3, 95%CI 0.13-0.75, P = 0.01). Cox-adjusted relative risks showed that MDR (RR 2.5, 95%CI 1.02-6.16, P = 0.04), HIV infection (RR 31.3, 95%CI 11.6-84.8, P < 0.001), and chronicity of tuberculosis (RR 2.1, 95%CI 1.0-4.4, P = 0.06) were associated with mortality, controlling for age. Predictors of retreatment were DR (not including MDR) (RR 2.2 95%CI 0.89-5.31, P < 0.087), MDR (RR 12.6, 95%CI 5.46-28.88, P < 0.001), and living in a household with an earthen floor (RR 2.8, 95%CI 1.27-6.13, P = 0.011). Being infected with MDR-TB was the only factor associated with a decreased likelihood of being in an RFLP cluster (OR 0.31, 95%CI 0.12-0.81, P = 0.02). CONCLUSIONS: Although MDR-TB may have a decreased propensity to spread and cause disease, it has a profoundly negative impact on tuberculosis control.

Adult↗
PubMed1999

Cefepime versus ceftazidime for the treatment of serious bacterial infections.

The objective of this open, comparative and randomized clinical trial was to compare the safety and efficacy of cefepime and ceftazidime in the treatment of adults with severe infections. Fifty patients were included; 25 received cefepime (1 g b.i.d.) and 25 ceftazidime (1 g t.i.d.). Demographic characteristics of the groups were similar. The drugs were well tolerated and adverse reactions were minor and comparable in both groups. Forty-four patients were evaluated (22 from each group). There was a satisfactory clinical response in 86% and 77% in the cefepime and ceftazidime groups, respectively. In patients with microbiologically documented infection 83% (15/18) treated with cefepime and 64% (9/14) treated with ceftazidime responded satisfactorily (no statistical significance). In conclusion, the data confirms that cefepime is as safe and effective as ceftazidime for the treatment of serious bacterial infections, with the advantage of being administrated only twice daily.

Adult↗
PubMed1999

Relatedness analyses of Histoplasma capsulatum isolates from Mexican patients with AIDS-associated histoplasmosis by using histoplasmin electrophoretic profiles and randomly amplified polymorphic DNA patterns.

The present paper analyzes the histoplasmin electrophoretic profiles and the randomly amplified polymorphic DNA (RAPD) patterns of the fungus Histoplasma capsulatum isolated from Mexican patients with AIDS-associated histoplasmosis. Clinical isolates from Guatemala, Colombia, and Panama, as well as H. capsulatum isolates from different sources in nature, were also processed. All histoplasmin samples shared four antigenic fractions of 200, 49, 10.5, and 8.5 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). According to their percentage of relatedness, based on SDS-PAGE histoplasmin electrophoretic image analysis, H. capsulatum isolates were divided in two groups: group A contained all AIDS-associated isolates studied and two human reference strains from Mexican histoplasmosis patients without AIDS; group B included bat guano, infected bat, and cock excreta isolates from the State of Guerrero, Mexico, plus three human histoplasmosis strains from Guatemala, Panama, and Colombia. Polymorphic DNA patterns evaluated by RAPD-PCR showed three major bands of 4.4, 3.2, and 2.3 kb in most H. capsulatum isolates studied. Four groups were related by DNA polymorphisms: group I was formed by most of the AIDS-associated H. capsulatum isolates studied, one human histoplasmosis strain from Colombia, two human reference strains from Mexican patients without AIDS, and one human histoplasmosis strain from Guatemala. Group II consisted of only a single strain from Panama. Group III included three strains: one from a Mexican patient with AIDS and two isolated from nature in Guerrero (cock excreta and bat guano). The last, group IV, consisted of only one strain isolated from an infected bat, captured in Guerrero. A tight relationship between phenotypic and genotypic characterization was observed, and both analyses could be useful tools for typing H. capsulatum from different sources and geographic origins.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Nocardiasis in patients with HIV infection.

The frequency of Nocardia infection in HIV-infected patients has increased during the past few years from 0.3% in 1985 to 1.8% in 1989. Although it is not of great concern as an AIDS-associated infection, the nonspecific clinical presentation in these patients might be confused with other lung infections such as tuberculosis (TB). The mortality rate can be as high as 60%. The authors diagnosed three homosexual men with nocardiasis among 1060 HIV-infected patients (0.2%) in a tertiary care center in Mexico City from 1981 to 1997. The mean age was 32 years. The CD4 count was less than 260 cells/mm3 in all these individuals. The clinical presentations were subacute sinusitis, chronic localized abdominal abscess, and acute disseminated nocardiasis. The respective associated infections were none; TB and cytomegalovirus (CMV); and candidiasis, TB, CMV, Isospora belli, and disseminated Mycobacterium avium complex (MAC). Trimethoprim/sulfamethoxazole (TMP/SMX) was the treatment in all the cases; at the time of this writing, two patients were living and one had died during the acute episode. A literature search uncovered 130 cases of Nocardia infection in HIV patients since 1982. According to the published data and our results, nocardiasis should be suspected in those HIV-infected patients who (1) do not respond to appropriate antituberculous treatment; (2) are intravenous drug users; and (3) develop a characteristic pericardial infection. Finally, adequate surgical or percutaneous drainage of abscesses are extremely valuable for diagnosis and therapy.

AIDS-Related Opportunistic Infections↗
PubMed1998

Oral manifestations in patients with Sjögren's syndrome.

OBJECTIVE: To investigate oral signs and symptoms in patients with Sjögren's syndrome (SS), and to compare results with a group of healthy individuals. METHODS. Each individual completed a questionnaire designed to investigate his/her perception of oral health and dryness, as well as a list of signs and symptoms associated with xerostomia. An oral clinical evaluation was performed. RESULTS: A total of 81 subjects were studied, 21 with primary SS, 29 with secondary SS, and 31 healthy individuals. Patients with SS considered that their oral health was poor. Oral dryness was perceived as intense. Symptoms most commonly expressed were: sensitivity to acids (68%), difficulty eating dry foods (66%), and sensitivity to spicy foods (58%). Dryness of the lips (76%) and the tongue (68%) were also among the most frequent complaints. Oral findings of patients with SS included cervical or atypical caries in 83%, fissured erythematous tongue in 70%, and oral candidiasis in 74%. Significant differences were found when results obtained from patients with SS were compared with the healthy group. CONCLUSION: The oral health of this group of patients with SS was deficient. Adequate management of dry mouth was not achieved, mainly for the modifiable components such as dental decay and oral candidiasis. Therefore. treatment and prevention plans are mandatory. These measures might help to reduce the discomfort associated with oral dryness and to reduce dental loss.

Female↗
PubMed1998

Oral candidiasis and Sjögren's syndrome.

OBJECTIVE: To determine the prevalence of oral candidiasis (OC) in patients with Sjögren's syndrome (SS), to identify oral signs and symptoms associated with OC, and to compare them with a healthy group. METHODS: Patients with primary SS, and with SS associated with autoimmune disease were identified according to established criteria. Each individual had: (1) a questionnaire, (2) an oral clinical evaluation, (3) a set of microbiological tests: tongue smear, culture of tongue smear, and saliva sample. Diagnosis of OC was established with 2 positive results and the presence of any sign or symptom. RESULTS: A total of 81 subjects were studied, 21 with primary SS, 29 secondary SS, and 31 healthy subjects. We diagnosed OC in 74% of patients with SS, which was statistically significant compared to the healthy group (23%) p < 0.001. Frequent symptoms associated with OC were increased sensitivity to spicy foods (58%) and unpleasant metallic taste (40%). Common signs of OC were erythematous lesion on the dorsum of the tongue (68%) and angular cheilitis (24%). CONCLUSION: Prevalence of OC was high in patients with SS. The frequency of signs and symptoms associated with OC may explain some of the clinical manifestations. If chronic erythematous OC is found in patients with SS an oral assessment at every appointment may help provide appropriate treatment.

Candidiasis, Oral↗
PubMed1996

Mycobacterial infection in Mexican AIDS patients.

To describe the characteristics of mycobacterial infection in Mexico, we reviewed records from patients who were seen at the AIDS Clinic of the National Institute of Nutrition in Mexico City from 1983 to 1992. Of 460 AIDS patients, 118 (25.6%) were found to have mycobacterial infections by positive Ziehl-Neelsen stain, culture, or both. Cultures were completed for 66 of the 118 stain-positive specimens. Mycobacterium tuberculosis was the most common species found (n = 13), followed by M. avium complex (n = 12); 21 infections were identified a nonspecific mycobacteria other than tuberculosis (MOTT) and 20 infections were from species other than tuberculosis. Susceptibility testing was performed in only two tuberculosis cases, with one strain showing multidrug resistance. We conclude that mycobacterial infection is common among our AIDS population, and MOTT may be at least as common as M. tuberculosis. Previous reports of the rarity of MOTT could be related to the lack of adequate diagnostic methods in developing countries.

AIDS-Related Opportunistic Infections↗
PubMed1996

Antimicrobial resistance in fecal flora: longitudinal community-based surveillance of children from urban Mexico.

We assessed the colonization patterns, over time, of three sentinel drug-resistant enteric bacterial genera in samples from a cohort of 20 healthy small children in a periurban community in Mexico. The children were monitored during a 13-week period by means of weekly home visits and examinations of stool collections. These specimens were tested for the presence of Escherichia coli, Klebsiella species, and Shigella species resistant to one or more of seven antimicrobial agents. Ninety, 77, and 62% of the stool specimens had E. coli isolates resistant to ampicillin, trimethoprim, and tetracycline, respectively. Simultaneous resistance to more than one antibiotic by an E. coli isolate was observed in 88.5% of stool samples. Persistent fecal shedding of ampicillin-, trimethoprim-, and tetracycline-resistant E. coli occurred during the study period in the majority of children. We detected colonization by E. coli resistant to chloramphenicol, gentamicin, nitrofurantoin, or norfloxacin, as well as by Klebsiella species and Shigella species resistant to one of these antibiotics, in fewer children and for shorter periods. These data suggest the common and persistent intestinal shedding of multidrug-resistant E. coli strains by small healthy children.

Ampicillin Resistance↗
PubMed1996

Piperacillin/tazobactam in the treatment of hospitalized patients with urinary tract infections: an open non-comparative and multicentered trial.

The aim of this multicentered, prospective and open study was to determine the clinical and bacteriological efficacy and safety of piperacillin/tazobactam (4g/500 mg IV tid) in the treatment of 79 adult patients with complicated urinary tract infections (UTI) requiring hospitalization. Forty-seven women and 32 men (mean age 54.2 years, and range 21-91) from 4 Argentinean and 6 Mexican hospitals were enrolled. Sixty-one clinically and bacteriologically evaluable patients were treated for a mean of 9.1 days (range 5-15). A favorable clinical response was seen in 83.6% and 80% at early and late assessment, respectively. Bacteriological eradication was achieved in 85.3% and 80% at early and late estimation, respectively. Escherichia coli was isolated in 33 cases, Klebsiella pneumoniae in 8, Enterococcus spp. in 7, Proteus mirabilis in 6, Pseudomonas aeruginosa in 3, Enterobacter spp. and Morganella morganii in 2. While 21% of all the clinical isolates were resistant to piperacillin, none of them was initially resistant to piperacillin/tazobactam. However, one female patient with a persistent UTI caused by E. coli developed resistance to piperacillin/tazobactam during treatment. A 64-year-old man with frontal meningioma developed purulent meningitis due to Enterobacter cloacae after neurosurgery. He was initially treated with ciprofloxacin, rifampin and amikacin and because of persistence of fever, he was moved to piperacillin/tazobactam. After 5 days of therapy, he developed coma secondary to intracranial hemorrhage and died. By then, the platelet count was normal (220,000/microliters), but the prothrombin time (19.5 seconds) and the partial thromboplastin time (63 seconds) were significantly prolonged. Our data suggest that piperacillin/tazobactam is a reliable therapy for complicated, non-complicated, community or hospital-acquired UTI.

Adult↗