Discusión de factores pronóstico en dos casos familiares de fiebre manchada de las Montañas Rocosas

Background: Rocky Mountain spotted fever is a public health problem in Mexico, with high regional case fatality rates. Little is known regarding prognostic factors such as nutritional and immunological condition, as well as bacterial inoculum. Clinical Cases: We report the cases of two siblings: a male of 9 (case 1) and a 10-yearold girl (case 2), from an urban location in southern Sonora, Mexico, with no heredofamilial or pathological history of relevance to the current condition. His diet included all the food groups, three times a day. They reported a history of contact with ticks, inside and outside their home, and living with ectoparasitized dogs with them. Both started with a similar clinical picture (fever, malaise and rash). Doxycycline was prescribed with the same scheme and day of evolution; however, one of the patients died and the other improved clinically, without apparent sequelae. According to clinical findings or laboratory tests, the diagnosis of Rocky Mountain Spotted Fever was established. Conclusions: It is possible that the difference on the prognosis of some patients it is related to nutritional and immunological status, as well as to the magnitude of bacterial inoculum. Future research is necessary to examine the role of such factors in the prognosis of patients with Rocky Mountain spotted fever.