[Rickettsial spotted fever in the Paraná Delta. An emerging disease]. / Fiebre manchada por rickettsias en el Delta del Paraná. Una enfermedad emergente.

We describe a case of rickettsial spotted fever in the Paraná Delta region of Buenos Aires province in Argentina. The patient developed an acute febrile syndrome characterized by myalgias, headache, asthenia and moderate odynophagia, followed by a diffuse macular, papular, and purpuric exanthema. The patient had been bitten recently by a tick on the left preauricular region and an erosive papular lesion was evident at the bite site. An indirect immunofluorescence antibody assay identified antibodies reactive with spotted fever group rickettsiae in the patient's serum. The patient improved rapidly with doxycycline. Several considerations relating to the identity of the rickettsial species and tick vector are discussed, including the possibility that this patient's illness may have been caused by Rickettsia parkeri.

Stocks of carbon and nitrogen and partitioning between above- and belowground pools in the Brazilian coastal Atlantic Forest elevation range.

We estimated carbon and nitrogen stocks in aboveground biomass (AGB) and belowground biomass (BGB) along an elevation range in forest sites located on the steep slopes of the Serra do Mar on the north coast of the State of São Paulo, southeast Brazil. In elevations of 100 m (lowland), 400 m (submontane), and 1000 m (montane) four 1-ha plots were established, and above- (live and dead) and belowground (live and dead) biomass were determined. Carbon and nitrogen concentrations in each compartment were determined and used to convert biomass into carbon and nitrogen stocks. The carbon aboveground stock (C(AGB)) varied along the elevation range from approximately 110 to 150 Mg·ha(-1), and nitrogen aboveground stock (N(AGB)), varied from approximately 1.0 to 1.9 Mg·ha(-1). The carbon belowground stock (C(BGB)) and the nitrogen belowground stock (N(BGB)) were significantly higher than the AGB and varied along the elevation range from approximately 200-300 Mg·ha(-1), and from 14 to 20 Mg·ha(-1), respectively. Finally, the total carbon stock (C(TOTAL)) varied from approximately 320 to 460 Mg·ha(-1), and the nitrogen total stock (N(TOTAL)) from approximately 15 to 22 Mg·ha(-1). Most of the carbon and nitrogen stocks were found belowground and not aboveground as normally found in lowland tropical forests. The above- and belowground stocks, and consequently, the total stocks of carbon and nitrogen increased significantly with elevation. As the soil and air temperature also decreased significantly with elevation, we found a significantly inverse relationship between carbon and nitrogen stocks and temperature. Using this inverse relationship, we made a first approach estimate that an increase of 1°C in soil temperature would decrease the carbon and nitrogen stocks in approximately 17 Mg·ha(-1) and 1 Mg·ha(-1) of carbon and nitrogen, respectively.

Fiebre manchada por rickettsias en el Delta del Paraná: Una enfermedad emergente / Rickettsial spotted fever in the Paraná Delta: An emerging disease

Se comunica un caso de fiebre manchada por rickettsia autóctono del delta del Paraná correspondiente a la provincia de Buenos Aires. Luego de cinco días de haber permanecido en una región cercana a la localidad de ingeniero Otamendi, partido de Campana, el paciente presentó un síndrome febril agudo caracterizado por hipertermia con escalofríos y sudoración, mialgias, cefalea, astenia y discreta odinofagia, seguido a las 72 horas por un exantema maculopapuloso congestivo con elementos purpúricos, de distribución universal. En la región preauricular izquierda se observaba una lesión papuloerosiva, producida cinco días antes de iniciada la fiebre por una garrapata adquirida en el lugar. El cuadro clínico remitió rápidamente con la administración de doxiciclina. Por inmunofluorescencia indirecta se identificaron anticuerpos reactivos contra el grupo de rickettsias causantes de fiebres manchadas (CDC, Atlanta, EE.UU.). Se realizan consideraciones sobre la especie de rickettsia, el vector involucrado y la posibilidad que la enfermedad fuera debida a Rickettsia parkeri.

We describe a case of rickettsial spotted fever in the Paraná Delta region of Buenos Aires province in Argentina. The patient developed an acute febrile syndrome characterized by myalgias, headache, asthenia and moderate odynophagia, followed by a diffuse macular, papular, and purpuric exanthema. The patient had been bitten recently by a tick on the left preauricular region and an erosive papular lesion was evident at the bite site. An indirect immunofluorescence antibody assay identified antibodies reactive with spotted fever group rickettsiae in the patient's serum. The patient improved rapidly with doxycycline. Several considerations relating to the identity of the rickettsial species and tick vector are discussed, including the possibility that this patient's illness may have been caused by Rickettsia parkeri.