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 participat ed during 1999-2000; they collected 1,806 isolates (Streptococcus pneumoniae 518, Haemophilus influenzae 520, Moraxella catarrhalis 140, Staphylococcus aureus 351, S. pyogenes 277). Overall, 218 (42.1 percent) of the S. pneumoniae isolates had reduced susceptibility to penicillin, 79 (15.3 percent) were penicillin-resistant and 79 (15.3 percent) were erythromycin-resistant. Mexico had the highest prevalence of penicillin (76.5 percent) and erythromycin (31.2 percent) 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 percent) produced b-lactamase, ranging from 11 percent (Brazil) to 24.5 percent (Mexico). Among M. catarrhalis isolates, 138 (98.6 percent) produced b-lactamase. Twenty-four (8.7 percent) 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 percent of the S. aureus isolates (Argentina 15 percent; Mexico 20 percent; Brazil 31.3 percent). Telithromycin was effective against 97.7 percent 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 b-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

A simple whole-blood test for detecting antibodies to human immunodeficiency virus.

We developed an immunochromatographic whole-blood test (WBT) which detects antibodies to human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) from fingerstick blood. The sensitivity and specificity of the WBT were 99.41% (1,018 confirmed positive patients) and 99.89% (941 uninfected patients), respectively (enzyme immunoassay [EIA] on serum or plasma as a reference). WBT performance was comparable to those of licensed EIAs and Western blotting, using 18 HIV-2 sera, 23 HIV-1 seroconversion panels, and a low-titer performance panel (in lieu of whole blood).

Crytococcus neoformans var. gattii in an AIDS patient: first observation in Mexico.

We report the first, as far as we know, Mexican case of meningitis caused by Cryptococcus neoformans var. gattii serotype B associated with AIDS in a female patient. The HIV was transmitted to the patient through a blood transfusion. This patient represents, worldwide, the ninth case of C. neoformans var. gattii in patients with AIDS.

A field test for the detection of antibodies to human immunodeficiency virus types 1 and 2 in serum or plasma.

In response to the need for simple and rapid tests for infectious diseases, we have devised a test for antibodies to human immunodeficiency virus type 1 (HIV-1) and HIV-2 which resembles many contemporary strip-style pregnancy tests in format and ease of use. The test was evaluated with 2,928 serum specimens (1,541 reactive and 1,387 nonreactive) collected and tested at a Mexico City hospital clinic and was compared with a laboratory assay (Abbott) performed simultaneously. The sensitivity and specificity of the test using these serum specimens were 99.68 and 99.71%, respectively (before the code of the blinded study was broken). This compares with 100% sensitivity and 97.55% specificity with the laboratory assay (specificity upon reassay after the code was broken, 99.21%). In a survey of HIV-2 specimens, reactive (positive) specimens were detected in 51 of 51 cases. The test was examined with 21 commercially available (HIV-1) seroconversion panels. The performance of the test was comparable to that of a group of Food and Drug Administration-approved (antibody-based) HIV tests.

PIP: Simple and rapid methods of detecting infectious disease are needed. The authors therefore developed a test for antibodies to HIV-1 and HIV-2 which resembles many contemporary strip-style pregnancy tests in both format and ease of use. The test was evaluated with 1541 reactive and 1387 nonreactive serum specimens collected and tested at a Mexico City hospital clinic. A laboratory assay was performed simultaneously. The sensitivity and specificity of the test using these serum specimens were 99.68% and 99.71%, respectively. The laboratory assay was 100% sensitive and 97.55% specific. All reactive HIV-2 specimens were detected. The test was examined with 21 commercially available HIV-1 seroconversion panels. The performance of the authors' test was comparable to that of a group of Food and Drug Administration approved HIV tests.

[The resistance and serotyping of 83 strains of Streptococcus pneumoniae isolated from asymptomatic carriers and ill children]. / Resistencia y serotipificación de 83 cepas de Streptococcus pneumoniae aisladas de niños portadores asintomáticos y enfermos.

Eight-three isolates of Streptococcus pneumoniae obtained from children hospitalized with several infections in Mexico City and Cuernavaca, and from healthy children attending a day-care center in Cuernavaca, from January to September 1992, were screened for antimicrobial resistance patterns by in vitro susceptibility testing against antimicrobial agents of potential use in the treatment of diseases caused by S. pneumoniae (39 infected patients and 44 from healthy children). 21.6% of strains were resistant to penicillin, 52% of the strains were multiresistant without a commun pattern. Children attending a day-care center had a higher rate of S. pneumoniae strains resistant to one or more antimicrobial than hospitalized children. Serotypes or serogroups 6, 23F, 14 and 19 were most prevalent. There are evidence that strain 23F has an intercontinental link, this strain is associated with disseminated diseases and multiresistance to antimicrobials. The results indicate that changes can occur in the susceptibility of S. pneumoniae and that selective susceptibility testing and epidemiologic studies in hospitalized patients and children in day-care centers are necessary.

Detection of specific antibodies in gingival crevicular transudate by enzyme-linked immunosorbent assay for diagnosis of human immunodeficiency virus type 1 infection.

The purpose of this open and multicenter trial was to determine the usefulness of antibody detection by enzyme-linked immunosorbent assay (ELISA) in gingival crevicular transudate (GCT), which was collected with an investigational device (Orasure; Epitope, Beaverton, Oreg.), for the diagnosis of human immunodeficiency virus type 1 (HIV-1) infection and to compare it with antibody detection in serum. A total of 1,880 individuals were tested, as follows: 354 HIV-1-infected individuals (111 asymptomatics individuals and 243 individuals with AIDS), 46 individuals with autoimmune diseases (AD), 296 individuals with dental diseases, 42 individuals with other chronic diseases, and 1,142 healthy individuals. Sera from 356 individuals and GCT from 354 individuals were positive for HIV-1 antibodies. There were two false-negative gingival samples, one from an HIV-1-positive asymptomatic individual and one from a patient with AIDS. HIV-1 antibodies were unexpectedly detected in both serum and GCT of two individuals, one with dental disease and one with pulmonary tuberculosis. None of the sera or GCTs from healthy subjects or patients with AD were positive. Compared with the serum assay, the sensitivity, specificity, and positive and negative predictive values of the GCT assay were 99.5, 100, 100, and 99.9%, respectively. Of 355 paired serum-GCT samples that were HIV-1 positive by ELISA and that were tested by Western blot (immunoblot), all were positive for HIV-1 by using the U.S. Public Health Service interpretation criteria, while among gingival samples, 301 were positive, 52 were indeterminate, and 2 were negative. Of 82 negative paired samples selected at random, 80 were negative by Western blotting of serum and GCT and 2 were indeterminate by Western blotting of serum and negative by Western blotting of GCT (a healthy blood donor and a patient with dermatopolymyositis). Testing for HIV-1 antibodies in GCT is a simple and reliable screening procedure in populations with high and low prevalences of infection because of the high sensitivity and specificity of the method, and it offers improved safety for hospital personnel.