Leptospirosis among patients presenting with dengue-like illness in Puerto Rico.

Leptospirosis is difficult to distinguish from dengue fever without laboratory confirmation. Sporadic cases/clusters of leptospirosis occur in Puerto Rico, but surveillance is passive and laboratory confirmation is rare. We tested for leptospirosis using an IgM ELISA on sera testing negative for dengue virus IgM antibody and conducted a case-control study assessing risk factors for leptospirosis, comparing clinical/laboratory findings between leptospirosis (case-patients) and dengue patients (controls). Among 730 dengue-negative sera, 36 (5%) were positive for leptospirosis. We performed post mortem testing for leptospirosis on 12 available specimens from suspected dengue-related fatalities; 10 (83%) tested positive. Among these 10 fatal cases, pulmonary hemorrhage and renal failure were the most common causes of death. We enrolled 42 case-patients and 84 controls. Jaundice, elevated BUN, hyperbilirubinemia, anemia, and leukocytosis were associated with leptospirosis (p < .01 for all). Male sex, walking in puddles, rural habitation, and owning horses were independently associated with leptospirosis. Epidemiological, clinical, and laboratory criteria may help distinguish leptospirosis from dengue and identify patients who would benefit from early antibiotic treatment.

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.

Immunogenicity of 2 serogroup B outer-membrane protein meningococcal vaccines: a randomized controlled trial in Chile.

CONTEXT: Meningococcal disease occurs worldwide, and serogroup B disease accounts for a large proportion of cases. Although persons younger than 4 years are at greatest risk for serogroup B meningococcal disease, vaccine efficacy has not been demonstrated in this age group. OBJECTIVE: To evaluate serum bactericidal activity (SBA) against homologous vaccine type strains and a heterologous Chilean epidemic strain of Neisseria meningitidis as a potential correlate for vaccine efficacy. DESIGN: Double-blind, randomized controlled trial conducted between March 14 and July 20, 1994. All blood samples were taken by December 1994. SETTING: Santiago, Chile, where a clonal serogroup B meningococcal disease epidemic began in 1993. PARTICIPANTS: Infants younger than 1 year (n = 187), children aged 2 to 4 years (n = 183), and adults aged 17 to 30 years (n = 173). INTERVENTION: Participants received 3 doses of outer-membrane protein (OMP) meningococcal vaccine developed in either Cuba or Norway or a control vaccine, with each dose given 2 months apart. Blood samples were obtained at baseline, prior to dose 3, and at 4 to 6 weeks after dose 3. MAIN OUTCOME MEASURE: Immune response, defined as a 4-fold or greater rise in SBA titer 4 to 6 weeks after dose 3 compared with prevaccination titer. RESULTS: Children and adult recipients of either meningococcal vaccine were more likely than controls to develop an immune response to the heterologous epidemic strain. After 3 doses of vaccine, 31% to 35% of children responded to the vaccine vs 5% to placebo; 37% to 60% of adults responded to vaccine vs 4% to placebo (P<.05 vs control for all). Infants, however, did not respond. In contrast, against homologous vaccine type strains, the response rate was 67% or higher among children and adults and 90% or higher among infants (P<.001 vs control for all). Subsequent SBA against 7 isogenic homologous target strains identified class 1 OMP as the immunodominant antigen. CONCLUSIONS: These data suggest that neither serogroup B OMP meningococcal vaccine would confer protection during a heterologous epidemic. However, epidemic strain-specific vaccines homologous for class 1 OMP are promising candidates for the control of epidemic serogroup B meningococcal disease.

Bacillary angiomatosis and other Bartonella species infections.

Infections with organisms of the genus Bartonella, for many years important only in South and Central America, have assumed significance in developing countries, especially in conjunction with the advent of the pandemic of the human immunodeficiency virus infection. New molecular and culture techniques have determined that these organisms cause new diseases such as bacillary angiomatosis as well as diseases the etiology of which have been unknown such as cat scratch disease. In this article, the microbiology, pathogenesis, histopathology and clinical manifestations of diseases caused by these organisms are discussed.

Angiomatosis bacilar y peliosis bacilar en pacientes infectados con el virus de la inmunodeficiencia humana / Bacillary angiomatosis and bacillary peliosis in patients infected with Human Inmunodeficiency Virus

Los Dres. Koehler y Tappero han estudiado ampliamente el problema de la infección por Rochalimaea en las personas infectadas con el virus de la inmunodeficiencia humana tipo 1 (HIV-1). Especies de este género provocan enfermedades como la fiebre de las trincheras y la enfermedad por arañazo de gato; en la actualidad también están siendo identificados como agentes etiológicos de enfermedad cutánea, visceral, ósea y de bacteriemias en los individuos infectados con el HIV-1. La principal consideración a tener en cuenta en el diagnóstico diferencial de las personas infectadas por HIV-1, está dada por el Sarcoma de Kaposi. Estos autores brindan un enfoque útil para arribar al diagnóstico y dan pautas sobre el tratamiento antibiótico de esta complicación infecciosa que acompaña a la inmunosupresión que es relativamente poco frecuente. Es importante reconocer esta infección, dado que sólo parece responder a una terapia antibiótica prolongada (que posiblemente se extienda durante toda la vida)

Angiomatosis bacilar y peliosis bacilar en pacientes infectados con el virus de la inmunodeficiencia humana / Bacillary angiomatosis and bacillary peliosis in patients infected with Human Inmunodeficiency Virus

Los Dres. Koehler y Tappero han estudiado ampliamente el problema de la infección por Rochalimaea en las personas infectadas con el virus de la inmunodeficiencia humana tipo 1 (HIV-1). Especies de este género provocan enfermedades como la fiebre de las trincheras y la enfermedad por arañazo de gato; en la actualidad también están siendo identificados como agentes etiológicos de enfermedad cutánea, visceral, ósea y de bacteriemias en los individuos infectados con el HIV-1. La principal consideración a tener en cuenta en el diagnóstico diferencial de las personas infectadas por HIV-1, está dada por el Sarcoma de Kaposi. Estos autores brindan un enfoque útil para arribar al diagnóstico y dan pautas sobre el tratamiento antibiótico de esta complicación infecciosa que acompaña a la inmunosupresión que es relativamente poco frecuente. Es importante reconocer esta infección, dado que sólo parece responder a una terapia antibiótica prolongada (que posiblemente se extienda durante toda la vida) (AU)