[The Wolf in Sheep's Clothing Leishmania tropica: Two Pediatric Visceral Cases].

According to the World Health Organization (WHO), leishmaniasis is a zoonotic/anthroponotic parasitic disease endemic in 99 countries. It is estimated that approximately 12 million people are infected with Leishmania spp. and 350 million people live at risk. Every year, two million new cases are added to these figures. One and a half million cases of zoonotic/anthroponotic cutaneous leishmaniasis and 500 000 cases of visceral leishmaniasis are reported annually. One person is estimated to to be infected with cutaneous leishmaniasis in every 20 seconds and visceral leishmaniasis causes 60 000 deaths. In this report, two pediatric cases diagnosed with visceral leishmaniasis were presented. In the study, bone marrow aspirations were performed to determine the etiology of the disease in an eight-month-old male patient with fever and hepatosplenomegaly who had been followed up in Manisa Celal Bayar University, Department of Pediatrics, Division of Pediatric Hematology with the diagnosis of severe glucose-6-phosphate dehydrogenase (G-6PD) deficiency since the neonatal period and in a nine-month-old female patient who had had a high fever and bicytopenia for two weeks. Bone marrow aspirations were cultured in NNN medium and their smears were stained and examined with Giemsa. rk-39 and Leishmania IFAT tests were performed by using patients' sera. Quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) analysis was also performed for Leishmania spp. Leishmania spp. amastigotes were observed in Giemsa-stained smear preparations, Leishmania spp. promastigotes were grown in NNN medium, rk39 rapid diagnostic kit was weakly positive, Leishmania IFAT was positive at a titer of 1/1024 and Leishmania tropica was identified as the causative agent by RT-qPCR analysis for both cases. These two cases suggested that fatal cases of visceral leishmaniasis may increase with the spread of visceralized isolates of L.tropica, the most common causative agent of cutaneous leishmaniasis in Türkiye, and this issue may create a significant public health problem.