Systemic Bartonella henselae Infection in Immunocompetent Adult Presenting as Fever of Unknown Origin

Hepatosplenic Cat Scratch Disease: Description of Two Cases Undergoing Contrast-Enhanced Ultrasound for Diagnosis and Follow-Up and Systematic Literature Review

Cat scratch disease (CSD) is a disease usually characterized by self-limited lymphadenopathy of the young man. Rarely CSD, however, can manifest itself as an unusual hepatosplenic form (HS-CSD) in immunocompetent patients. HS-CSD diagnosis is generally based on clinical features, imaging, and serologies, but sensitivity of serologies is very variable, like that of other diagnostic methods, as Warthin-Starry silver stain and isthology. Also there are no specific markers for the follow-up. The use of the CEUS (abdominal contrast-enhanced ultrasound) in HS-CSD is not previously described in literature examined, but we think that CEUS can be of help to diagnosis and follow-up of these patients, even after an initial CT scan, because it is a sensitive method, as seen in other diseases associated with granulomas, such as sarcoidosis. We describe 2 new cases of HS-CSD, and we performed a systematic review of the clinical cases reported in the past 10 years in the literature associated to an analysis of clinical, diagnostic, and therapeutic aspects of the disease.

Cat Scratch Disease Presenting as Fever of Unknown Origin Is a Unique Clinical Syndrome

BACKGROUND

Fever of unknown origin (FUO) is a rare manifestation of cat scratch disease (CSD). Data regarding CSD-associated FUO (CSD-FUO), particularly in adults, are limited. We aimed to study disease manifestations and long-term clinical outcome.

METHODS

A national CSD surveillance study has been conducted in Israel since 1991. Data are obtained using questionnaires, review of medical records, and telephone interviews. FUO was defined as fever of ≥14 days without an identifiable cause. CSD-FUO patients were identified in the 2004-2017 CSD national registry. Follow-up included outpatient clinic visits and telephone/e-mail surveys.

RESULTS

The study included 66 CSD-FUO patients. Median age was 35.5 years (range, 3-88). Median fever duration was 4 weeks (range, 2-9). Relapsing fever pattern was reported in 52% of patients, weight loss in 57%, and night sweats in 48%. Involvement of ≥1 organs occurred in 59% of patients; hepatosplenic space-occupying lesions (35%), abdominal/mediastinal lymphadenopathy (20%), ocular disease (18%), and multifocal osteomyelitis (6%) were the most common. Malignancy, particularly lymphoma, was the initial radiological interpretation in 21% of patients; 32% underwent invasive diagnostic procedures. Of the 59 patients available for follow-up (median duration, 31 weeks; range, 4-445), 95% had complete recovery; 3 patients remained with ocular sequelae.

CONCLUSION

This is the first attempt to characterize CSD-FUO as a unique syndrome that may be severe and debilitating and often mimics malignancy. Relapsing fever is a common clinical phenotype. Multiorgan involvement is common. Recovery was complete in all patients except in those with ocular disease.

Cat Scratch Disease: The First Case Report in Republic of North Macedonia

Cat scratch disease (CSD) is the main clinical manifestation caused by Bartonella henselae in immuno-competent patients. The bacterium is transmitted to humans from cats via scratches or bites. In this case report, we are presenting to our knowledge the first etiologically confirmed case of CSD in our country. Here we describe the case of a previously healthy adult female patient presenting with fever and axillar lymphadenopathy over 1-month period. She underwent numerous clinical and paraclinical investigations for potential etiologies associated with lymphadenopathy and fever. Finally, serological testing for B.henselae was performed with titers for IgG 1:1024 and 1:160 for IgM, which confirmed the diagnosis. Five-day treatment with azithromycin resulted with good clinical response and complete recovery. We proved that CSD is a reality in our country and this report should raise awareness in medical doctors, especially infectious disease specialist. Also, CSD should be included in differential diagnosis in patients with fever of unkown origin (FUO), who are presenting with regional lymphadenopathy, with or without history of cat contact.

Bartonella henselae infection induces a persistent mechanical hypersensitivity in mice

Bartonella spp. are re-emerging and neglected bacterial pathogens. The natural reservoirs for several species of this genus are domestic animals such as cats and dogs, the most common pets in the USA and Brazil. Some cat studies suggest that the infection is more prevalent in tropical and poverty-stricken areas. These bacteria were associated with a wide spectrum of clinical manifestations: fever of unknown origin, endocarditis, angiomatosis, chronic lymphadenopathy, hepatitis, fatigue, paresthesia and pain. Our group has already demonstrated that B. henselae -infected sickle cell disease mice present with hyperalgesia. We hypothesized that even immunocompetent mice infected by B. henselae would show an increased and persistent mechanical sensitivity. Five ten-week old male BALB/c mice were intraperitoneally inoculated with a 30 µL of suspension containing 10 4 CFU/mL of B. henselae, while five others were inoculated with an equal volume of saline solution. Four days after bacterial inoculation, the mechanical paw withdrawal threshold was measured using von Frey filaments in all animals, for five consecutive days. The infected animals showed hypersensitivity to mechanical stimuli for five consecutive days. The present study has demonstrated that B. henselae infection induces persistent mechanical hypersensitivity, a signal consistent with pain.

Seroprevalence of Bartonella Species in Patients with Ocular Inflammation

Bartonella species, vector-borne etiologic agents of many systemic or self-limited infections, are responsible for a widening spectrum of diseases in humans, including inflammatory conditions of the eye. The aim of this study was to determine whether there is any relationship between uveitis and the evidence of Bartonella spp. infection in the serum, ocular fluid, and cataract mass in patients with intraocular inflammation. Polymerase chain reaction (PCR)-based tests and DNA sequencing were performed on surgery-extracted specimens of intraocular fluid and lens mass of 33 patients. Sera from 51 patients and 101 control subjects were tested for the presence of specific antibodies against Bartonella spp. Neither IgM-class antibodies against Bartonella spp. nor Bartonella spp. DNA were detected. A specific IgG-class antibody was found in 33.3% of the patients with uveitis. The rate of positive Bartonella serology was higher among the uveitis patients than that in control subjects. This high rate may in part result from unrecognized indirect mechanisms rather than the immediate presence and multiplication of Bartonella spp. in the eyeball. Nonetheless we believe that screening for Bartonella spp. should become part of the diagnostic workup in uveitis.

Multifocal splenic abscesses in immunocompetent adult due to cat-scratch disease

BACKGROUND

Cat-scratch disease is caused by Bartonella henselae and transmitted to humans via the cats. Patients usually present with cutaneous lesions, regional lymphadenopathy and a brief period of fever.

CASE REPORT

We report a rare case of an isolated splenic cat-scratch disease in an immunocompetent 27-year-old woman who presented with prolonged fever and multifocal splenic lesions. The patient was treated successfully with a long course of antibiotics.

CONCLUSION

Isolated splenic lesions and fever is a rare manifestation of the cat-scratch disease. There is need of high suspicion index by the physicians to diagnose the disease promptly without invasive methods. Hippokratia 2016, 20(4): 306-308.

Cat-scratch disease presenting as a solitary splenic abscess in an elderly man

Patients with cat-scratch disease (CSD), which is caused by Bartonella henselae, typically present with local lymphadenopathy with a brief period of fever and general symptoms. Most cases are self-limiting and usually afflict children and young adults. Although rare, CSD can lead to serious complications, especially in immunocompromised patients. These rare complications often require intensive treatment. We describe the case of a 79-year-old man who presented with general malaise and a high fever. The physical examination findings were unremarkable. Of note, the lymph nodes were not enlarged. An abdominal CT scan with intravenous contrast revealed a solitary splenic abscess and no lymphadenopathy. The initial antibiotic treatment was ineffective and a splenectomy was indicated. A history of contact with cats raised the possibility of CSD, which was confirmed by a positive serology test result for B henselae. Antibiotic treatment with azithromycin successfully treated the splenic abscess and splenectomy was avoided.

Hepatosplenic cat scratch disease in immunocompetent adults: report of 3 cases and review of the literature

Cat-scratch disease (CSD) is the most frequent presentation of Bartonella henselae infection. It has a worldwide distribution and is associated with a previous history of scratch or bite from a cat or dog. CSD affects children and teenagers more often (80%) than adults, and it usually has a self-limiting clinical course. Atypical clinical course or systemic symptoms are described in 5%-20% of patients. Among them, hepatosplenic (HS) forms (abscess) have been described. The majority of published cases have affected children or immunosuppressed patients. Few cases of HS forms of CSD in immunocompetent adult hosts have been reported, and data about the management of this condition are scarce. Herein, we present 3 new cases of HS forms of CSD in immunocompetent adults and review 33 other cases retrieved from the literature. We propose an approach to clinical diagnosis and treatment with oral azithromycin.

Visceral cat scratch disease with endocarditis in an immunocompetent adult: a case report and review of the literature

Infective endocarditis and hepatosplenic abscesses are rare manifestations of cat scratch disease (CSD), especially among immunocompetent adults. An otherwise healthy woman who presented with fever and abdominal pain was diagnosed with multiple abscesses in the spleen and the liver, as well as a mitral valve vegetation. PCR on spleen tissue was positive for Bartonella henselae. Prolonged treatment with doxycycline and gentamicin led to complete recovery. Review of the literature revealed 18 cases of hepatosplenic CSD in immunocompetent adults; the majority presented with fever of unknown origin and abdominal pain. In most cases the causative organism was B. henselae and the pathological findings were necrotizing granulomas, similar to the pathological features in classic CSD. Concomitant endocarditis was diagnosed in one case. Because Bartonella is one of the leading pathogens of culture-negative endocarditis, we raise the question of whether a comprehensive evaluation for endocarditis is needed in cases of systemic CSD.

Bartonella henselae bacteremia in a mother and son potentially associated with tick exposure

BACKGROUND

Bartonella henselae is a zoonotic, alpha Proteobacterium, historically associated with cat scratch disease (CSD), but more recently associated with persistent bacteremia, fever of unknown origin, arthritic and neurological disorders, and bacillary angiomatosis, and peliosis hepatis in immunocompromised patients. A family from the Netherlands contacted our laboratory requesting to be included in a research study (NCSU-IRB#1960), designed to characterize Bartonella spp. bacteremia in people with extensive arthropod or animal exposure. All four family members had been exposed to tick bites in Zeeland, southwestern Netherlands. The mother and son were exhibiting symptoms including fatigue, headaches, memory loss, disorientation, peripheral neuropathic pain, striae (son only), and loss of coordination, whereas the father and daughter were healthy.

METHODS

Each family member was tested for serological evidence of Bartonella exposure using B. vinsonii subsp. berkhoffii genotypes I-III, B. henselae and B. koehlerae indirect fluorescent antibody assays and for bacteremia using the BAPGM enrichment blood culture platform.

RESULTS

The mother was seroreactive to multiple Bartonella spp. antigens and bacteremia was confirmed by PCR amplification of B. henselae DNA from blood, and from a BAPGM blood agar plate subculture isolate. The son was not seroreactive to any Bartonella sp. antigen, but B. henselae DNA was amplified from several blood and serum samples, from BAPGM enrichment blood culture, and from a cutaneous striae biopsy. The father and daughter were seronegative to all Bartonella spp. antigens, and negative for Bartonella DNA amplification.

CONCLUSIONS

Historically, persistent B. henselae bacteremia was not thought to occur in immunocompetent humans. To our knowledge, this study provides preliminary evidence supporting the possibility of persistent B. henselae bacteremia in immunocompetent persons from Europe. Cat or flea contact was considered an unlikely source of transmission and the mother, a physician, reported that clinical symptoms developed following tick exposure. To our knowledge, this is the first time that a B. henselae organism has been visualized in and amplified from a striae lesion. As the tick bites occurred three years prior to documentation of B. henselae bacteremia, the mode of transmission could not be determined.

Diagnosis and follow-up of Bartonella henselae infection in the spleen of an immunocompetent patient by real-time quantitative PCR

Systemic Bartonella henselae infections are unusual in immunocompetent adults. However, here we report one such case of bartonellosis in a 34-year-old patient, who presented with fever and multinodular splenomegaly. We also describe a novel method of identifying Bartonella henselae by real-time quantitative polymerase chain reaction and sequencing of amplified products. This could prevent splenic bartonellosis being mistaken for lymphoma and thereby avert unnecessary splenectomy.