First identification of Anaplasma phagocytophilum in both a biting tick Ixodes nipponensis and a patient in Korea: a case report

Abstract

Background Human granulocytic anaplasmosis (HGA) is a tick-borne infectious disease caused by Anaplasma phagocytophilum. To date, there have been no reported cases of A. phagocytophilum infection found in both the biting tick and the patient following a tick bite. Case presentation An 81-year-old woman presented with fever following a tick bite, with the tick still intact on her body. The patient was diagnosed with HGA. The tick was identified as Ixodes nipponensis by morphological and molecular biological detection methods targeting the 16S rRNA gene. The patient’s blood was cultured after inoculation into the human promyelocytic leukemia cell line HL-60. A. phagocytophilum growth was confirmed via culture and isolation. A. phagocytophilum was identified in both the tick and the patient’s blood by Anaplasma-specific groEL- and ankA-based nested polymerase chain reaction followed by sequencing. Moreover, a four-fold elevation in antibodies was observed in the patient’s blood. Conclusion We report a case of a patient diagnosed with HGA following admission for fever due to a tick bite. A. phagocytophilum was identified in both the tick and the patient, and A. phagocytophilum was successfully cultured. The present study suggests the need to investigate the possible incrimination of I. nipponensis as a vector for HGA in Korea.

Molecular Detection of Anaplasma phagocytophilum and Ehrlichia Species in Ticks Removed from Humans in the Republic of Korea

“…Moreover, Xu et al [39] investigated the infection prevalence of B. burgdorferi sensu lato, B. miyamotoi, and A. phagocytophilum in human-biting ticks collected over a 10-year period in three western states of the US [39]. However, studies on TBPs in the ROK have primarily been conducted on wild or domesticated animals, such as goats [23], deer [24], and cattle [25], and several sporadic cases have been reported in patients with tick bites or in individuals visiting local hospitals [26,27]. To the best of our knowledge, this is the first report of a nationwide survey to test ticks removed from humans in the ROK.…”

“…Recently, 16 ticks collected between 2014 and 2017 from residents of the southwestern region of the ROK tested positive for A. phagocytophilum (three ticks), Babesia gibsoni (one tick), B. microti (two ticks), and Rickettsia spp. (12 ticks) [26], with A. phagocytophilum infection detected in both ticks and patients [27]. However, no research has been conducted based on nationwide surveys.…”

Molecular investigation of tick-borne pathogens in ticks removed from tick-bitten humans in the southwestern region of the Republic of Korea

“…In particular, we detected the same pathogen with A. phagocytophilum in Tick30 and the blood of these tick-bitten patients. It has been identified via PCR and increased antibody levels (IgG/IgM) using an indirect immunofluorescence assay according to the sample collection date of these patients [22]. Further study will need to be conducted to analyze patient characteristics from clinical data of more ticks and these tick-bitten patients.…”

Platelet phagocytosis by leukocytes in a patient with cerebral hemorrhage and thrombocytopenia caused by gram-negative bacterial infection

“…The pathogenic mechanism of human granulocytic anaplasmosis (HGA) is mainly that the function of neutrophils is damaged following infection by pathogens, resulting in abnormal adhesion, migration, neutrophil degranulation, and phagocytosis, which in turn cause a series of immunopathological changes. 9 In this case, the patient had fever and thrombocytopenia, and the possibility of Anaplasma phagocytophilum infection existed. However, considering that the cause of the disease was clear in this case, HGA could be excluded.…”