Micro Paper

Leishmania: Protozoan Parasite New Key Findings L Leishmania is an infectious parasitic protozoan. It is spread by the phlebotomine sand fly (blood-sucking fly) and upon introduction into a host, Leishmania uses its flagella to possibly puncture holes into macrophages, allowing entrance. Upon entrance into the macrophage, Leishmania’s flagella start to diminish and division occurs rapidly causing the macrophage to lyse, releasing more infectious cells. Acquiring Leishmania leads to cutaneous (skin sores) or visceral (internal organ damage). Common symptoms of cutaneous Leishmaniasis are painful/painless volcano resembling skin sores and swollen glands. Visceral symptoms are fever, weight loss, enlargement of the spleen and liver, low white and red blood cell count, along with low platelet count. Diagnosing methods include blood tests that detect antibody, such as the ELISA, and tissue sample examination using blood agar, microscopy, and quantitative nucleic acid sequencebased amplification. According to the Centers for Disease Control and Prevention, about ninety percent of Leishmania infections occur throughout Afghanistan, Algeria, Iran, Iraq, Saudi Arabia, Syria, Brazil, Peru ,Bangladesh, Nepal, and Sudan, but can occur in the U.S because of immigration. Currently a new treatment discovery has been made to alleviate visceral strains of Leishmania and recent studies show how quantitative nucleic acid sequence-based amplification helps distinguish if treatment has been effective. Visceral Leishmaniasis is caused by Leishmania donovani and produces about five hundred thousand new cases each year(“Division of Parasitic Diseases” CDC.gov). It can incubate in a host for several months and sometimes years. A new treatment approach was discovered in 2008, contributing to the relief of numerous people. A single-dose of liposome amphotericin B followed by a short course of miltefosine can alleviate visceral Leishmaniasis and prevent oncoming drug resistance (Barry 70). Two hundred twenty-six patients age twelve years and older with the disease were selected to participate in a study of four different treatment groups ( A,B,C,D). The groups received different dosage amounts of amphotericin B and miltefosine for a certain duration of time. For example, group A only received five milligrams per day of liposomal amphotericin B and group B received liposomal amphotericin B plus one hundred milligrams of miltefosine per day for approximately ten days (“New treatment approach for visceral leishmaniasis active“ 7). Due to the absence of miltefosine, the patients of group A had a higher death and relapse percentage, while the other groups had no death and minimal relapse (one percent). Ninety-seven percent of the groups patients were cured within nine months which led to a high success rate of using the two drugs together (“New treatment approach for visceral leishmaniasis active“ 7). A shorter approach to curing visceral Leishmania is viable by allowing the time of miltefosine therapy and the amount of liposome amphotericin B administered to be reduced. This new treatment approach is supported by scientific data and proves itself as a successful alleviating tool for Leishmania donovani. Also a new diagnostic test that helps monitor responses to cutaneous Leishmania treatment is called quantitative nucleic acid sequence-based amplification (QT-NASBA assay). This assay can assist in finding treatment mishaps of cutaneous Leishmania at an early level, which can help prevent a negative clinical outcome. One hundred thirty-seven skin biopsies were collected from fifty-three patients with cutaneous Leishmania six weeks after treatment (van der Meide 397). After QT-NASBA measured the parasitic load, neither a positive or negative correlation was associated with the treatment. Eighty percent of people not cured by the end of treatment had a positive test result for large amounts of parasites still present six weeks after the treatment, which shows that the assay can help predict the treatment outcome. Forty-three out of the fifty-three people were labeled as cured at the sixth month follow up due to assistance from QT-NASBA (van der Meide 394) . A prominent relationship was found between QT-NASBA results at the end of the first treatment and clinical outcome. Without this test people are unaware of the positive or negative result of the treatment on Leishmania.

Provided with the assay people infected are guaranteed an increased chance at curing the infection. The visceral Leishmaniasis treatment and quantitative nucleic acid sequencebased amplification diagnostic assay both represent new key findings about Leishmania. They are prominent advancements that can benefit the treatment of Leishmaniasis. Visceral treatment includes the usage of liposome amphotericin B and miltefosine to cure the infection and prevent resistance. The quantitative nucleic acid sequence-based amplification assay helps diagnose if the patient will need further treatment after the initial treatment. Positive and negative correlations in regards to parasitic infection treatment help the patient decipher if further actions are needed to take place. In result to both of these findings, treatment and diagnosis for Leishmania is helping patients to achieve a lasting cure. .