Comparison of a quantitative PCR assay with peripheral blood smear examination for detection and quantitation of Babesia microti infection in humans

Persistence of babesiosis for >2 years in a patient on rituximab for rheumatoid arthritis

“…On 11/1/13, 4.44 log10 copies/mL of whole blood of the target babesia DNA were detected by the qPCR on a blood sample, despite uninterrupted treatment with azithromycin 500 mg orally per day along with 750 mg twice daily of atovaquone since 5/13/13. On 11/15/13 while continuing on the same anti-babesia drug regimen, 4.29 log10 copies/mL were still detected, which, although a lower value, was not considered a significant decrease based on the anticipated degree of test variability of the qPCR assay used [4]. Although based on limited data, one approach that has been successful for managing babesiosis in such patients is to continue anti-babesia treatment until the effects of rituximab on the immune system have reversed, which may take approximately 18 months [1].…”

“…3 PCR testing began to be performed by an academic medical center starting on 11/1/13 utilizing a real time quantitative PCR (qPCR) assay targeting the gene encoding 18S rRNA of B. microti, as described elsewhere [3,4]. On 11/1/13, 4.44 log10 copies/mL of whole blood of the target babesia DNA were detected by the qPCR on a blood sample, despite uninterrupted treatment with azithromycin 500 mg orally per day along with 750 mg twice daily of atovaquone since 5/13/13.…”

Genome-wide diversity and gene expression profiling of Babesia microti isolates identify polymorphic genes that mediate host-pathogen interactions

“…Recent studies using a short-term in vitro culture as well as immunocompromised mice have shown that, of the four drugs used for treatment of human babesiosis, only atovaquone shows efficacy against the parasite in mouse red blood cells both in vitro and in vivo 11. These results, along with the shortcomings of available diagnostic tools to distinguish between past and active infection to prevent transfusion-transmitted babesiosis, have stimulated efforts to improve therapies and diagnostics111213141516171819.…”

Autoimmune hemolytic anemia associated with babesiosis

“…Patient was maintained on methylprednisolone for AIHA. Blood parasite smear was negative for blood parasites, but babesia microti DNA PCR was persistently positive [25, 26], for which patient was continued on antibiotics. His overall status improved and patient was discharged home with oral antibiotics and prednisone.…”