Gollob K J, Viana A G, Dutra W O
Graduate Program in Medicine and Biomedicine, Institute for Education and Research, Hospital Santa Casa, Belo Horizonte, MG, Brazil; National Institute for Science and Technology - Tropical Diseases (INCT-DT), Belo Horizonte, MG, Brazil.
Parasite Immunol. 2014 Aug;36(8):367-76. doi: 10.1111/pim.12100.
Leishmaniasis covers a broad spectrum of diseases with distinct, and sometimes overlapping, characteristics. The common thread in all forms of leishmaniasis is the infection by the parasite Leishmania belonging to the genus Leishmania. Upon infection of humans, there can be at least three outcomes, (i) control of Leishmania by the host immune response resulting in asymptomatic disease, (ii) patent infection and development of a relatively mild form of leishmaniasis and (iii) patent infection and development of severe clinical forms. The factors that determine the outcome of an initial inoculation with Leishmania are many, with the species of Leishmania representing one of the strongest predictive factors for the development of a given clinical form of disease. This is seen with L. braziliensis and L. amazonensis, infection leading mostly to tegumentary forms of disease, and L. infantum with the potential to induce visceral disease. However, it is also clear that the host immune response is a key factor in disease progression, not only responsible for control of Leishmania, but also playing an important role in disease progression and pathology. This duality between protective and pathogenic immune responses in individuals infected with Leishmania in the Americas is the focus of this review.
利什曼病涵盖了一系列具有不同特征（有时相互重叠）的疾病。所有形式的利什曼病的共同特点是由利什曼属的寄生虫利什曼原虫感染引起。人类感染后至少会出现三种结果：（i）宿主免疫反应控制利什曼原虫，导致无症状疾病；（ii）显性感染并发展为相对轻度的利什曼病；（iii）显性感染并发展为严重的临床形式。决定初次感染利什曼原虫结果的因素众多，其中利什曼原虫的种类是特定临床疾病形式发展的最强预测因素之一。这在巴西利什曼原虫和亚马逊利什曼原虫中可见，感染主要导致皮肤型疾病，而婴儿利什曼原虫有可能引发内脏疾病。然而，很明显宿主免疫反应是疾病进展的关键因素，不仅负责控制利什曼原虫，还在疾病进展和病理过程中发挥重要作用。美洲感染利什曼原虫个体中保护性和致病性免疫反应之间的这种双重性是本综述的重点。
