Pleural and pericardial effusions with fever and altered mental status: an atypical presentation of bartonellosis.

A male in his 60s presented to the emergency department (ED) with a 3-week history of fever and progressive confusion. Initial laboratory and radiographic workup was largely unremarkable except for moderate bilateral pleural effusions. The patient was admitted on broad-spectrum antibiotics and further workup for fever of unknown aetiology. The differential diagnosis was broadened to different zoonotic infections, and subsequent laboratory testing showed a markedly elevated Bartonella henselae IgG and Bartonella quintana IgG (1:4096 and 1:512, respectively) in addition to positive B. henselae IgM titre (>1:20). During hospitalisation, the patient became more hypoxic and was found to have enlarging pleural effusions as well as a new pericardial effusion. The patient was treated with intravenous then oral doxycycline 100 mg two times per day and oral rifampin 300 mg two times per day for 4 weeks with subsequent improvement in clinical status as well as both effusions. This case highlights a unique presentation of Bartonella and its rare manifestation of pleural and pericardial effusions.

Presumed acute posterior multifocal placoid pigmentary epitheliopathy associated with Bartonella infection.

To report a unique case of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) in a patient with positive serology for Bartonella, presenting with ocular signs and symptoms not attributable to other diseases. A 27-year-old woman presented with decreased visual acuity in both eyes. Multimodal fundus image analysis was performed. A color fundus photograph of both eyes revealed peripapillary and macular yellow-white placoid lesions. The fundus autofluorescence of both eyes demonstrated hypo- and hyperautofluorescence of the macular lesions. Fluorescein angiography showed early-stage hypofluorescence and late staining of placoid lesions in both eyes. Spectral domain optical coherence tomography (SD-OCT) of both eyes revealed irregular elevations in the retinal pigment epithelium with the disruption of the ellipsoid zone on the topography of macular lesions. At 3 months after the treatment initiation for Bartonella infection, the placoid lesions became atrophic and hyperpigmented, and SD-OCT revealed loss of both the outer retinal layers and retinal pigment epithelium on the topography of macular lesions in both eyes.

Seroprevalence of arthropod-borne bacterial infections in homeless individuals in Hamburg in 2020.

PURPOSE: The number of homeless people in Germany is steadily increasing. Due to their often precarious living conditions, this specific population may be increasingly exposed to ectoparasites that can transmit various pathogens. To assess the prevalence and thus the risk of such infections, we analyzed the seropositivity of rickettsiosis, Q fever, tularemia and bartonellosis in homeless individuals. METHODS: A total of 147 homeless adults from nine shelters in Hamburg, Germany, were included. The individuals underwent questionnaire-based interviewing, physical examination, and venous blood was drawn between May and June 2020. Blood samples were analyzed for antibodies against rickettsiae (Rickettsia typhi and R. conorii), Coxiella burnetii, Francisella tularensis and bartonellae. RESULTS AND CONCLUSION: A very low seroprevalence of R. typhi and F. tularensis infection was found (0-1%), while antibodies against R. conorii and C. burnetii were more common (7% each), followed by a relatively high seroprevalence of 14% for bartonellosis. Q fever seroprevalence was associated with the country of origin, whereas bartonellosis seroprevalence was associated with the duration of homelessness. Preventive measures targeting ectoparasites, especially body lice, should be put in place continuously.

Infectious endocarditis caused by Bartonella henselae associated with infected pets: two case reports.

BACKGROUND: Blood culture-negative infective endocarditis is a potentially severe disease that can be associated with infectious agents such as Bartonella spp., Coxiella burnetti, Tropheryma whipplei, and some fungi. CASE PRESENTATION: Reported here are two cases of blood culture-negative infective endocarditis in patients with severe aortic and mitral regurgitation in Brazil; the first case is a 47-year-old white man and the second is a 62-year-old white woman. Bartonella henselae deoxyribonucleic acid was detectable in the blood samples and cardiac valve with vegetation paraffin-fixed tissue samples. Additionally, an investigation was carried out on patients' pets, within the context of One Health, and serum samples collected from cats and dogs were reactive by indirect immunofluorescence assay. CONCLUSIONS: Even though the frequency of bartonellosis in Brazil is unknown, physicians should be aware of the possibility of blood culture-negative infective endocarditis caused by Bartonella, particularly in patients with weight loss, kidney changes, and epidemiological history for domestic animals.

Detection of Bartonella henselae DNA in the blood of patients with livedoid vasculopathy.

BACKGROUND: Livedoid vasculopathy (LV) manifests as ulcers and atrophic white scars on the lower extremities. The main known etiopathogenesis is hypercoagulability with thrombus formation, followed by inflammation. Thrombophilia, collagen and myeloproliferative diseases may induce LV, but the idiopathic (primary) form predominates. Bartonella spp. may cause intra-endothelial infection and skin manifestations caused by these bacteria may be diverse, including leukocytoclastic vasculitis and ulcers. OBJECTIVE: The aim of this study was to investigate the presence of bacteremia by Bartonella spp. in patients with difficult-to-control chronic ulcers diagnosed as primary LV. METHODS: Questionnaires and molecular tests (conventional PCR, nested PCR and real-time PCR) were applied and liquid and solid cultures were performed in the blood samples and blood clot of 16 LV patients and 32 healthy volunteers. RESULTS: Bartonella henselae DNA was detected in 25% of LV patients and in 12.5% of control subjects but failed to reach statistically significant differences (p = 0.413). STUDY LIMITATIONS: Due to the rarity of primary LV, the number of patients studied was small and there was greater exposure of the control group to risk factors for Bartonella spp. CONCLUSION: Although there was no statistically significant difference between the groups, the DNA of B. henselae was detected in one of every four patients, which reinforces the need to investigate Bartonella spp. in patients with primary LV.

Haemophagocytic lymphohistiocytosis associated with bartonella peliosis hepatis following kidney transplantation in a patient with HIV.

Bacillary peliosis hepatis is a well recognised manifestation of disseminated Bartonella henselae infection that can occur in immunocompromised individuals. Haemophagocytic lymphohistiocytosis is an immune-mediated condition with features that can overlap with a severe primary infection such as disseminated Bartonella spp infection. We report a case of bacillary peliosis hepatis and secondary haemophagocytic lymphohistiocytosis due to disseminated Bartonella spp infection in a kidney-transplant recipient with well controlled HIV. The patient reported 2 weeks of fever and abdominal pain and was found to have hepatomegaly. He recalled exposure to a sick dog but reported no cat exposures. Laboratory evaluation was notable for pancytopenia and cholestatic injury. The patient met more than five of eight clinical criteria for haemophagocytic lymphohistiocytosis. Pathology review of a bone marrow core biopsy identified haemophagocytosis. A transjugular liver biopsy was done, and histopathology review identified peliosis hepatis. Warthin-Starry staining of the bone marrow showed pleiomorphic coccobacillary organisms. The B henselae IgG titre was 1:512, and Bartonella-specific DNA targets were detected by peripheral blood PCR. Treatment with doxycycline, increased prednisone, and pausing the mycophenolate component of his transplant immunosuppression regimen resulted in an excellent clinical response. Secondary haemophagocytic lymphohistiocytosis can be difficult to distinguish from severe systemic infection. A high index of suspicion can support the diagnosis of systemic Bartonella spp infection in those who present with haemophagocytic lymphohistiocytosis, especially in patients with hepatomegaly, immunosuppression, and germane animal exposures.

Bartonella and Coxiella infections presenting as systemic vasculitis: case series and review of literature.

OBJECTIVES: Coxiella and Bartonella spp. display particular tropism for endothelial or endocardial tissues and an abnormal host response to infections with induced autoimmunity. We aimed, through a case series combined with a comprehensive literature review, to outline characteristics of Coxiella and Bartonella infections presenting as systemic vasculitis. METHODS: We retrospectively included cases of definite Coxiella and Bartonella infections presenting with vasculitis features and performed a comprehensive literature review. RESULTS: Six cases of Bartonella infections were added to 18 cases from literature review. Causative pathogens were mainly B. henselae. Bartonella infection mimicked ANCA-associated vasculitis in 83% with PR3-ANCA and presented as cryoglobulinaemic vasculitis in 8%. GN was present in 92%, and 88% had endocarditis. Complement fractions were low in 82% and rheumatoid factor positive in 85%. Kidney biopsies showed cell proliferation, mostly crescentic, with pauci-immune GN in 29%. Outcome was favourable, with the use of antibiotics alone in one-third. Five cases of Coxiella infections were added to 16 from literature review. Sixteen had small-vessel vasculitides, mainly cryoglobulinaemia vasculitis in 75%. One patient had polyarteritis nodosa-like vasculitis and four large-vessel vasculitis. Outcome was good except for one death. A highly sensitive next generation sequencing analysis on three Coxiella- and two Bartonella-related vasculitides biopsies did not find any bacterial DNA. CONCLUSION: Coxiella and Bartonella are both able to induce vasculitis but display distinct vasculitis features. Bartonella mimics PR3-ANCA-associated vasculitis in the setting of endocarditis, whereas Coxiella may induce vasculitis involving all vessel sizes.

Bartonella species as a cause of culture-negative endocarditis in South Africa.

Previous reports have highlighted the high prevalence of blood culture negative endocarditis (BCNE) in South Africa. The Tygerberg Endocarditis Cohort (TEC) study is an ongoing prospective cohort study of patients with confirmed or suspected IE presenting to Tygerberg Academic Hospital, Cape Town, South Africa. Current analysis includes patients that presented between November 2019 and August 2020. Forty four (44) patients have been included in this ongoing study. Fourteen of the 44 patients (31.8%) had BCNE. Further analysis of the patients with BCNE identified Bartonella species as the most common causative organism (n=6; 43%). Other causes included Mycoplasma species (n=2). No cause could be identified in 4 of the 44 patients (9%). Bartonella quintana was identified with PCR of valvular tissue as the causative organism in 4 of the 5 patients that underwent urgent surgery. The patients with Bartonella IE (n=6) had an average age of 39 years with equal gender distribution. The common clinical features were clubbing (n=5; 83%), anemia (n=4; 66.6%), haematuria (n=3; 50%), acute on chronic severe regurgitant lesion (n=3; 50%) and acute severe regurgitant lesion (n=2; 33.3%).The aortic valve was involved in 5 of 6 patients. During a mean follow-up period of 251 days after diagnosis, no major adverse events occurred. Bartonella-associated IE is an important cause of BCNE in the Western Cape of South Africa. Imaging findings (in patients with BCNE) of significant valvular destruction with large vegetations on the aortic valve not affected by congenital or rheumatic valve disease should raise the suspicion of Bartonella-associated IE.

Systemic Bartonellosis Manifesting With Endocarditis and Membranoproliferative Glomerulonephritis.

Cat scratch disease caused by Bartonella species is mostly benign and self-limiting condition. Systemic infection is uncommon in immunocompetent host. We describe the case of a 66-year-old male who presented with sudden painless left eye blindness and brown-colored urine. Laboratory findings revealed progressively rising serum creatinine in association with nephrotic-range proteinuria at 7 g/day and glomerular hematuria on urinalysis. An echocardiogram demonstrated mitral and tricuspid valve vegetations despite multiple negative blood cultures. The left eye blindness was attributed to retinal artery occlusion from septic valvular embolus. Kidney biopsy showed membranoproliferative glomerulonephritis pattern of injury with "full house" pattern on immunofluorescent staining with subendothelial deposits on electron microscopy. Markedly elevated IgG (immunoglobulin G) titers for B henselae and B quintana were discovered. The patient had several cats at home. Kidney failure rapidly progressed to require hemodialysis. Once the diagnosis of systemic bartonellosis was confirmed, doxycycline (for 4 months) with rifampicin (for 3 months) were initiated. Repeat echocardiogram in 4 months demonstrated a resolution of valvular vegetations; however, the left eye blindness was permanent. In the present case the correct diagnosis of systemic bartonellosis allowed institution of appropriate antibiotic therapy and to also achieve a partial recovery of renal function and to discontinue hemodialysis.

Prevalence of Bartonella spp. Infection in Patients with Sickle Cell Disease.

Background: The inherent characteristics of the sickle cell disease (SCD), the most common genetic hematological disorder, increase the propensity of infections. Bartonella spp. are emerging and neglected bacteria. A large spectrum of clinical manifestations has been linked to bartonella bloodstream infection in the last two decades that can cause fatal outcomes, especially in immunodeficient patients. The goal of this study was to evaluate the prevalence of bartonella infection in SCD patients. Materials and Methods: We evaluated Bartonella spp. prevalence in 107 SCD patients. Blood samples and enrichment blood cultures were analyzed by molecular detection of Bartonella spp. DNA. Bartonella DNA was amplified using conventional genus-specific Bartonella PCR which amplifies the Intergenic Transcribed Spacer region and Bartonella henselae-specific nested PCR which amplifies the FtsZ gene. Positive patient DNAs were tested with ssrA conventional PCR. All amplicons were sequenced. Findings: Ten of 107 patients tested positive for B. henselae infection in at least one molecular test. All obtained amplicons were sequenced and similar to B. henselae sequences deposited in GenBank (accession number BX897699). Based on statistical results, bloodstream infection with B. henselae was not associated with animal contact or blood transfusions. Conclusion: We detected B. henselae DNA in 10 (9.3%) SCD studied patients. These patients were notified and treatment was offered to them.

Rare Presentation of Endocarditis and Mycotic Brain Aneurysm.

Bartonella endocarditis can be an elusive diagnosis. The clinical manifestations can vary and, at times, include multiorgan involvement. This case report describes 2 patients who presented with multiorgan failure, cerebral mycotic aneurysms, and valvular endocarditis secondary to Bartonella infection. The complex diagnosis, decision making, and surgical management are described.

The seroprevalence of Bartonella spp. in the blood of patients with musculoskeletal complaints and blood donors, Poland: a pilot study.

BACKGROUND: Bartonella spp. can cause a variety of diseases, such as lymphadenopathies, cat scratch disease, and trench fever, but can also give rise to many non-specific symptoms. No data exists regarding the prevalence of Bartonella spp. in patients with musculoskeletal complaints, nor among blood donors in Poland. METHODS: The presence of anti-Bartonella IgM and IgG in the serum of blood donors (n = 65) (Lodz, Poland) and in the patients of the Department of Rheumatology Clinic (n = 40) suffering from musculoskeletal symptoms was tested by immunofluorescence. Blood samples were cultured on enriched media. Epidemiological questionnaires were used to identify key potential risk factors, such as sex, age, contact with companion animals, and bites from insects or animals. RESULTS: Altogether, 27 of the 105 tested subjects were seropositive for Bartonella henselae IgG (23%) and three for Bartonella quintana IgG (2.85%); IgMs against B. henselae were found in three individuals (2.85%), and IgMs against B. quintana were found in one (1.54%). No statistically significant difference was found between the prevalence of B. henselae in the blood of donors or patients and the presence of unexplained musculoskeletal complaints (23% vs 30%). Individuals who had kept or been scratched by cats were not more likely to be B. henselae seropositive (p > 0.01). Tick bites were more commonly reported in patients, but insignificantly (p > 0.01). CONCLUSION: This is the first report of a high seroprevalence of anti-Bartonella IgG in patients with musculoskeletal symptoms and in blood donors in Poland. The obtained results indicate that such seroprevalence may have a possible significance in the development of musculoskeletal symptoms, although it should be confirmed on a larger group of patients. Asymptomatic bacteremia might occur and pose a threat to recipients of blood from infected donors. Hence, there is a need for more detailed research, including molecular biology methods, to clarify the potential risk of Bartonella spp. being spread to immunocompromised individuals. KEY POINTS: • This is the first study presenting high seroprevalence of Bartonella spp. in Poland. • IgG and IgM antibodies against B. quintana were found in blood samples of blood donors.

Transient myocardial thickening in a Bartonella henselae-positive cat.

A 3-year-old castrated male domestic shorthair presented to the Cornell University Hospital for Animals for acute onset respiratory distress. Thoracic radiographs, echocardiogram, and electrocardiogram (ECG) revealed left-sided congestive heart failure, myocardial thickening with left atrial dilation, and sinus rhythm conducted with a left bundle branch block, respectively. Cardiac troponin I was elevated and continued to increase over 36 h (1.9 ng/mL, 3.1 ng/mL, and 3.5 ng/mL, sequentially every 12 h). The cat tested positive for Bartonella henselae and was treated with azithromycin (30 mg/kg by mouth (PO) every 24 h for 30 days), along with furosemide (1 mg/kg PO every 24 h), benazepril (0.4 mg/kg PO every 24 h), pimobendan (0.23 mg/kg PO every 12 h), and clopidogrel (18.75 mg PO every 24 h). Reevaluation at 6 weeks revealed normal respiratory rate on physical examination, normal cardiac structures and function on echocardiogram, resolution of left bundle branch block on ECG, and normal cardiac troponin I levels (0.06 ng/mL). All medications were discontinued at this time, and the cat continued to do well 5 months after reevaluation. Here, we report a case of transient myocardial thickening in a cat that was also positive for B. henselae.

A miraculous recovery: Bartonella henselae infection following a red ant bite.

Infections caused by the Bartonella species are responsible for the human diseases collectively called 'bartonellosis'. The clinically important human infections are mostly caused by the three species (eg, B. bacilliformis, B. quintana and B. henselae) of Bartonella out of the many progressively increasing identified species. Bartonella henselae transmitted by the arthropod vector, fleas, after cat bite is responsible for the rare multisystem cat scratch disease in humans. We present an extremely rare case of B. henselae contracted presumably through a red ant bite. The patient had a prolonged hospital stay for persistent encephalopathy due to delay in diagnosis and initiation of antimicrobial therapy. His hospital course was complicated by two episodes of pulseless electrical activity cardiac arrest related to pulmonary embolism. However, he recovered to his baseline status in the hospital with timely administration of systemic anticoagulation and antimicrobials. He was discharged home with no neurological deficits.

EVALUATING THE IMPACTS OF COINFECTION ON IMMUNE SYSTEM FUNCTION OF THE DEER MOUSE ( PEROMYSCUS MANICULATUS) USING SIN NOMBRE VIRUS AND BARTONELLA AS MODEL PATHOGEN SYSTEMS.

: Simultaneous infections with multiple pathogens can alter the function of the host's immune system, often resulting in additive or synergistic morbidity. We examined how coinfection with the common pathogens Sin Nombre virus (SNV) and Bartonella sp. affected aspects of the adaptive and innate immune responses of wild deer mice ( Peromyscus maniculatus). Adaptive immunity was assessed by measuring SNV antibody production; innate immunity was determined by measuring levels of C-reactive protein (CRP) in blood and the complement activity of plasma. Coinfected mice had reduced plasma complement activity and higher levels of CRP compared to mice infected with either SNV or Bartonella. However, antibody titers of deer mice infected with SNV were more than double those of coinfected mice. Plasma complement activity and CRP levels did not differ between uninfected deer mice and those infected with only Bartonella, suggesting that comorbid SNV and Bartonella infections act synergistically, altering the innate immune response. Collectively, our results indicated that the immune response of deer mice coinfected with both SNV and Bartonella differed substantially from individuals infected with only one of these pathogens. Results of our study provided unique, albeit preliminary, insight into the impacts of coinfection on immune system function in wild animal hosts and underscore the complexity of the immune pathways that exist in coinfected hosts.