Manifestation of anaplasmosis as cerebral infarction: a case report

Severe Fatal ARDS Due to Untreated Human Granulocytic Anaplasmosis in a 67-Year-Old Man: A Case Report

BACKGROUND Anaplasmosis, or human granulocytic anaplasmosis (HGA), is a tick-borne diseased caused by a gram-negative, intracellular bacterium, Anaplasma phagocytophilum. HGA usually presents with mild symptoms but can be more severe. This report describes a 67-year-old male resident of rural Pennsylvania, admitted to the hospital after a fall, who developed fatal acute respiratory distress syndrome (ARDS) associated with human granulocytic anaplasmosis (HGA) following transmission of Anaplasma phagocytophilum by a tick bite (Ixodes scapularis). CASE REPORT A 67-year-old man, resident of rural Pennsylvania, with history of diabetes mellitus, presented after falling from a 7-foot-tall ladder, sustaining right-sided hemopneumothorax, multiple right rib fractures, and unstable T12 vertebra fracture. He required tube thoracostomy and underwent T9-L2 posterior spinal fusion surgery. His initial labs showed leukopenia, thrombocytopenia, and elevated transaminase levels. His course was complicated by cardiac arrest and acute respiratory failure, consistent with severe ARDS. He received high positive end-expiratory pressure (PEEP) ventilation, prone positioning, and neuromuscular paralysis to improve refractory hypoxemia. Bronchoalveolar lavage (BAL) for bacterial, fungal, viral pathogens, Covid-19, respiratory viral panel, Mycoplasma pneumoniae, and Chlamydia pneumoniae were negative. his family withdrew medical care, knowing the patient's own wishes, and the patient died. Polymerase chain reaction (PCR) for Anaplasma DNA came back positive after the patient's death. His peripheral smear was then examined, showing morulae inside the cytoplasm of infected neutrophils.   CONCLUSIONS This report describes the atypical presentation of a case of HGA and highlights that in parts of the world where tick-borne diseases are endemic, disease awareness, high index of clinical suspicion, and early diagnosis and management are required.

Anaplasmosis encephalitis and infection of non-myeloid bone marrow precursors

Due to climate change, infections from tickborne pathogens are becoming more prevalent in the Northern Hemisphere. Human granulocytic anaplasmosis, caused by the obligate intracellular gram-negative bacteria Anaplasma phagocytophilum and carried by Ixodes ticks, can lead to morbidity and mortality in select populations. Anaplasmosis is commonly accompanied by significant cytopaenia, the pathophysiology of which remains unknown. Our case report describes an uncommon meningoencephalitic presentation of anaplasmosis with substantial anaemia and thrombocytopaenia. Additionally, we propose a mechanism of bone marrow infection and suppression by A. phagocytophilum which may be responsible for the cytopaenia in anaplasmosis and provide pictographic evidence of anaplasma in peripheral blood, cerebrospinal fluid and bone marrow.

Anaplasma phagocytophilum Encephalitis: A Case Report and Literature Review of Neurologic Manifestations of Anaplasmosis

Anaplasma phagocytophilum is an obligate intracellular, Gram-negative pathogen, causative agent of Human Granulocytic Anaplasmosis (HGA). HGA usually manifests as a non-specific febrile illness, accompanied by evidence of leucopenia, thrombocytopenia, and an alteration in liver enzymes. Neurologic manifestations of anaplasmosis are rare and rarely reported. We describe a 62-year-old man who developed encephalitis due to an Anaplasma phagocytophilum infection. The patient favorably responded to intravenous doxycycline and recovered without neurological sequela. In the tick endemic area, clinicians should have a high index of suspicion for tick-borne diseases in patients presenting with neurological deficits. A prompt diagnosis and treatment lead to improvements in morbidity and mortality.

Anaplasma phagocytophilum Community-Acquired Pneumonia: Case Report and Literature Review

Anaplasma phagocytophilum is an emerging, Gram-negative, and obligate intracellular pathogen that is infrequently implicated as a causative agent of community-acquired pneumonia. In this paper, we report about an immunocompetent patient from the community who presented with fever, cough, and shortness of breath. Chest X-ray and CT showed bilateral lung infiltrates. Extensive workup for other common and uncommon causes of pneumonia was positive for anaplasmosis. The patient recovered completely with doxycycline therapy. In our literature review, we find that in 80% of reported cases of anaplasmosis pneumonia, empiric treatment did not contain doxycycline, which in some cases led to acute respiratory distress syndrome. Clinicians in tick-borne disease endemic regions should be aware of this unusual presentation of anaplasmosis in order to be able to select appropriate antimicrobial regimens and initiate timely management.

Human Granulocytic Anaplasmosis

Human granulocytic anaplasmosis (HGA) is a bacterial infection caused by Anaplasma phagocytophilum and transmitted by the bite of the black-legged (deer tick) in North America. Its incidence is increasing. HGA can be transmitted after 24 to 48 hours of tick attachment. The incubation period is 5 to 14 days after a tick bite. Symptoms include fever, chills, headache, and myalgia. Complications include shock, organ dysfunction, and death. Mortality is less than 1% with appropriate treatment. Doxycycline is first line treatment for all ages. Start it empirically if symptoms and risk factors suggest HGA. PCR is the confirmatory test of choice.

Human Granulocytic Anaplasmosis-A Systematic Review of Published Cases

Anaplasma phagocytophilum is an emerging, Gram-negative, obligate intracellular pathogen that is transmitted by a tick vector. Human infection ranges from asymptomatic to severe disease that can present with pancytopenia, multiorgan failure, and death. The aim of this systematic review is to analyze case reports and case series reported over the last two decades in peer-reviewed journals indexed in the Medline/PubMed database according to the PRISMA guidelines. We found 110 unique patients from 88 case reports and series. The most common mode of transmission was tick bite (60.9%), followed by blood transfusion (8.2%). Infection was acquired by blood transfusion in nearly half (42%) of the immunocompromised patients. Most patients reported fever (90%), followed by constitutional (59%) and gastrointestinal symptoms (56%). Rash was present in 17% of patients, much higher than in previous studies. Thrombocytopenia was the most common laboratory abnormality (76%) followed by elevated aspartate aminotransferase (AST) (46%). The diagnosis was most commonly established using whole-blood polymerase chain reaction (PCR) in 76% of patients. Coinfection rate was 9.1% and Borrelia burgdorferi was most commonly isolated in seven patients (6.4%). Doxycycline was used to treat 70% of patients but was only used as an empiric treatment in one-third of patients (33.6%). The overall mortality rate was 5.7%, and one patient died from trauma unrelated to HGA. The mortality rates among immunocompetent and immunocompromised patients were 4.2% (n = 4/95) and 18.2% (n = 2/11), respectively. Four of the six patients who died (66.6%) received appropriate antibiotic therapy. Among these, doxycycline was delayed by more than 48 h in two patients.

Anaplasmosis in Poland - analysis of 120 patients

The aim of our study was to clarify the clinical picture of anaplasmosis through analysis of the symptoms and clinical signs presented by infected patients in a cohort of tick-bitten individuals. The study included 1375 patients with suspicion of tick-borne disease. Finally, 120 patients (8.7%) were diagnosed with anaplasmosis (HGA). Blood samples were examined by PCR for Anaplasma phagocytophilum, Candidatus Neoehrlichia mikurensis, Borrelia burgdorferi sensu lato, Babesia spp., and Bartonella spp.. Based on analysis of 120 patients with HGA we concluded that anaplasmosis is not as rare in Europe, as it is thought to be and often appears as a co-infection with other tick-borne pathogens. The co-infection rate of patients with A. phagocytophilum infection in tick endemic areas is high. Co-infection of A. phagocytophilum with B. burgdorferi s.l. or tick-borne encephalitis virus may influence symptom frequency. PCR together with medical history, clinical picture and basic laboratory tests is a sufficient method for the diagnosis of anaplasmosis. Doxycycline is an effective drug leading to complete recovery.

Genetic diversity of Anaplasma bacteria: Twenty years later

The genus Anaplasma (family Anaplasmataceae, order Rickettsiales) includes obligate intracellular alphaproteobacteria that multiply within membrane-bound vacuoles and are transmitted by Ixodidae ticks to vertebrate hosts. Since the last reclassification of Anaplasmataceae twenty years ago, two new Anaplasma species have been identified. To date, the genus includes eight Anaplasma species (A. phagocytophilum, A. marginale, A. centrale, A. ovis, A. bovis, A. platys, A. odocoilei, and A. capra) and a large number of unclassified genovariants that cannot be assigned to known species. Members of the genus can cause infection in humans and a wide range of domestic animals with different degrees of severity. Long-term persistence which, in some cases, is manifested as cyclic bacteremia has been demonstrated for several Anaplasma species. Zoonotic potential has been shown for A. phagocytophilum, the agent of human granulocytic anaplasmosis, and for some other Anaplasma spp. that suggests a broader medical relevance of this genus. Genetic diversity of Anaplasma spp. has been intensively studied in recent years, and it has been shown that some Anaplasma spp. can be considered as a complex of genetically distinct lineages differing by geography, vectors, and host tropism. The aim of this review was to summarize the current knowledge concerning the natural history, pathogenic properties, and genetic diversity of Anaplasma spp. and some unclassified genovariants with particular attention to their genetic characteristics. The high genetic variability of Anaplasma spp. prompted us to conduct a detailed phylogenetic analysis for different Anaplasma species and unclassified genovariants, which were included in this review. The genotyping of unclassified genovariants has led to the identification of at least four distinct clades that might be considered in future as new candidate species.

A Case of Anaplasmosis during a Warm Minnesota Fall

A healthy 33 year old male presented in December with a 3 week history of fever and fatigue. He had been deer-hunting in northern Minnesota 1 month prior and had sustained a tick bite. Extensive laboratory investigations and a lumbar puncture were conducted. He was empirically with doxycycline and had rapid improvement in his symptoms. Subsequently, PCR and serologic testing returned positive for Anaplasma phagocytophlium. Anaplasmosis is a tick-borne illness caused by the bacterium Anaplasma phagocytophilum and is typically seen in the warmer months. This patient’s presentation in December was uncommon for a tick-borne illness in Minnesota. Regional weather records demonstrated unseasonably warm temperatures during the patient’s trip. Ixodes ticks are known to be sensitive to temperature and humidity, which likely contributed to increased tick activity, leading to disease transmission. This case highlights the importance for clinicians to be aware of local weather patterns and how this might influence seasonal disease presentations.

The Impact of Tick-Borne Diseases on the Bone

Tick-borne infectious diseases can affect many tissues and organs including bone, one of the most multifunctional structures in the human body. There is a scarcity of data regarding the impact of tick-borne pathogens on bone. The aim of this review was to survey existing research literature on this topic. The search was performed using PubMed and Google Scholar search engines. From our search, we were able to find evidence of eight tick-borne diseases (Anaplasmosis, Ehrlichiosis, Babesiosis, Lyme disease, Bourbon virus disease, Colorado tick fever disease, Tick-borne encephalitis, and Crimean-Congo hemorrhagic fever) affecting the bone. Pathological bone effects most commonly associated with tick-borne infections were disruption of bone marrow function and bone loss. Most research to date on the effects of tick-borne pathogen infections on bone has been quite preliminary. Further investigation of this topic is warranted.

Asymptomatic-anaplasmosis confirmation using genetic and serological tests and possible coinfection with spotted fever group Rickettsia: a case report

Background

Anaplasmosis is an emerging acute febrile disease that is caused by a bite of an Anaplasma phagocytophilum–infected hard tick. As for healthy patients, reports on asymptomatic anaplasmosis resulting from such tick bites are rare.

Case presentation

A 55-year-old female patient visited the hospital with a tick bite in the right infraclavicular region. The tick was suspected to have been on the patient for more than 10 days. PCR and an indirect immunofluorescence assay (IFA) were performed to identify tick-borne infectious diseases. The blood sample collected at admission yielded a positive result in nested PCR targeting Ehrlichia- or Anaplasma-specific genes groEL and ankA. Subsequent sequencing confirmed the presence of A. phagocytophilum, and seroconversion was confirmed by the IFA involving an A. phagocytophilum antigen slide. PCR detected no Rickettsia-specific genes [outer membrane protein A (ompA) or surface cell antigen 1 (sca1)], but seroconversion of spotted fever group (SFG) rickettsiosis was confirmed by an IFA.

Conclusions

This study genetically and serologically confirmed an asymptomatic A. phagocytophilum infection. Although SFG rickettsiosis was not detected genetically, it was detected serologically. These findings indicate the possibility of an asymptomatic coinfection: anaplasmosis plus SFG rickettsiosis. It is, therefore, crucial for clinicians to be aware of potential asymptomatic anaplasmosis following a tick bite.

Rickettsial infections of the central nervous system

As a result of migrations and globalization, people may face a possible increase in the incidence of central nervous system rickettsial infections (CNS R). These diseases, caused by Rickettsia species and transmitted to humans by arthropod bites, are putatively lethal. However, the diagnosis of CNS R is challenging and often delayed due to their nonspecific clinical presentation and the strict intracellular nature of rickettsiae. Furthermore, transfer of rickettsiae to the brain parenchyma is not yet understood. The aim of this review is to analyze and summarize the features and correlated findings of CNS R in order to focus attention on these intriguing but frequently neglected illnesses. We also incorporated data on CNS infections caused by Rickettsia-related microorganisms.

Novel variants of the newly emerged Anaplasma capra from Korean water deer (Hydropotes inermis argyropus) in South Korea

BACKGROUND

Anaplasma spp. are tick-borne Gram-negative obligate intracellular bacteria that infect humans and a wide range of animals. Anaplasma capra has emerged as a human pathogen; however, little is known about the occurrence and genetic identity of this agent in wildlife. The present study aimed to determine the infection rate and genetic profile of this pathogen in wild animals in the Republic of Korea.

METHODS

A total of 253 blood samples [198 from Korean water deer (Hydropotes inermis argyropus), 53 from raccoon dogs (Nyctereutes procyonoides) and one sample each from a leopard cat (Prionailurus bengalensis) and a roe deer (Capreolus pygargus)] were collected at Chungbuk Wildlife Center during the period 2015-2018. Genomic DNA was extracted from the samples and screened for presence of Anaplasma species by PCR/sequence analysis of 429 bp of the 16S rRNA gene marker. Anaplasma capra-positive isolates were genetically profiled by amplification of a longer fragment of 16S rRNA (rrs) as well as partial sequences of citrate synthase (gltA), heat-shock protein (groEL), major surface protein 2 (msp2) and major surface protein 4 (msp4). Generated sequences of each gene marker were aligned with homologous sequences in the database and phylogenetically analyzed.

RESULTS

Anaplasma capra was detected in blood samples derived from Korean water deer, whereas samples from other animal species were negative. The overall infection rate in tested samples was 13.8% (35/253) and in the water deer the rate was 17.8% (35/198), distributed along the study period from 2015 to 2018. Genetic profiling and a phylogenetic analysis based on analyzed gene markers revealed the occurrence of two distinct strains, clustered in a single clade with counterpart sequences of A. capra in the database.

CONCLUSIONS

Anaplasma capra infection were detected in Korean water deer in the Republic of Korea, providing insight into the role of wildlife as a potential reservoir for animal and human anaplasmosis. However, further work is needed in order to evaluate the role of Korean water deer as a host/reservoir host of A. capra.