A Multiplex PCR assay for a differential diagnostic of rickettsiosis, Lyme disease and scrub typhus

Background & objectives: Coexistence of tick-borne diseases in some regions in Latin America makes the diagnosis difficult due to shared initial signs and symptoms. Rickettsiosis, Lyme disease and recently, scrub typhus are gaining more importance. The objective of this study is to develop a multiplex-PCR assay for a differential diagnosis of rickettsiosis, Lyme disease and scrub typhus. Methods: By using bibliographic and bioinformatic analysis, we identify candidate regions to perform the multiplexPCR assay for Rickettsia sp., Borrelia burgdorferi and Orientia tsutsugamushi as well as identify optimal melting temperature and sensibility analysis. Results: We identified specific primer pairs for Rickettsia sp, Borrelia burgdorferi and Orientia tsutsugamushi with different PCR fragment length but a common melting temperature, 58°C. Interpretation & conclusion: We successfully developed a Multiplex PCR assay for differential diagnosis of rickettsiosis, Lyme disease and scrub typhus that could be a rapid and easy option in clinical and epidemiological practice.Laboratorio de Enfermedades Infecciosas y Parasitarias 1. Unidad Interinstitucional de Investigación Clínica y Epidemiológica, Facultad de Medicina, Universidad Autónoma de Yucatán. Yucatán, Mexico

Laboratorio de Enfermedades Emergentes y Re-emergentes. Centro de Investigaciones Regionales “Dr. Hideyo Noguchi”. Universidad Autonoma de Yucatan. Yucatán, Mexico

A Case of Intraerythrocytic Parasitism Treated with Quinine and Clindamycin / 감염

Although rapid diagnosis of human babesiosis usually can be made by microscopic examination of thin and thick blood smears, differentiation between Babesia microti and Plasmodium falciparum can be quite difficult. The parasite is often not visualized in the early course of infection or in a partially treated case and the young trophozoites of these two organisms are similar. Recently, we experienced a case, which was thought as human babesiosis initially by microscopic examination of the Giemsa-stained thin blood smears, but was finally diagno-sed as P. falcifarum infection by indirect immunofluorescent antibody assay and polymerase chain reaction. The patient was treated successfully with quinine and clindamycin, which are effective in both infections. When differential diagnosis is difficult, we suggest combination therapy of quinine and clindamycin as an empirical regimen.

An Imported Case of Babesiosis / 감염

Babesiosis is a tick-borne, malaria-like illness caused by Babesia species that infect erythrocytes of mammals incidentally. The family Babesiidae is characterized by consisting of non-pigmented intraerythrocytic parasites that reproduce within erythrocytes by asynchronous, asexual budding into two or four daughter cells (tetrad). We experienced a case of human babesiosis presenting fever and chills. The patient was a 49-year old man, who had been in Africa (Ethiopia, Uganda). Three weeks before admission intermittent spiking fever had developed, which had been accompanied by severe chills. The peripheral blood smear (Giemsa-stain) revealed characteristic forms of an intracellular quadruplet parasite compatible with Babesia. The patient was improved significantly by the treatment with quinine and clindamycin for a week.