Detection by immunofluorescence assay of Bartonella henselae in lymph nodes from patients with cat scratch disease

Limitations of Serological Diagnosis of Typical Cat Scratch Disease and Recommendations for the Diagnostic Procedure

Introduction

Cat scratch disease (CSD) is the most common cause of bacterial infectious lymphadenopathy, especially in children, but its diagnosis still remains challenging. Serological assays are widely applied due to their simplicity and the non-invasive sampling. However, these techniques present several limitations, including not well-defined antigen preparation, assay conditions and cutoff titers, severe cross-reactions with other species and organisms, and the notably ranging seroprevalence in the normal population. The objective of this study is to review the literature in order to determine the best diagnostic procedure for the diagnosis of CSD.

Methods

Databases including PubMed, Medline, Google Scholar, and Google were searched to determine the best diagnostic procedure for the diagnosis of CSD. A total of 437 papers were identified and screened, and after exclusion of papers that did not fulfill the including criteria, 63 papers were used.

Results

It was revealed that sensitivities of serological assays varied from 10% to 100%. Indeed, more than half of the studies reported a sensitivity lower than 70%, while 71% of them had a sensitivity lower than 80%. Moreover, specificities of serological assays ranged from 15% to 100%, with 25 assays reporting a specificity lower than 90%.

Conclusion

It is considered that molecular assays should be the gold standard technique for CSD confirmation, and physicians are reinforced to proceed to lymph node biopsy in suspicious CSD cases.

Canine and Feline Parasitology: Analogies, Differences, and Relevance for Human Health

Cats and dogs are treated as family members by most pet owners. Therefore, a high quality of veterinary care and preventive medicine is imperative for animal health and welfare and for the protection of humans from zoonotic pathogens. There is a general perception of cats being treated as "small dogs," especially in the field of clinical parasitology. As a result, several important differences between the two animal species are not taken into proper consideration and are often overlooked. Dogs and cats are profoundly different under evolutionary, biological, ethological, behavioral, and immunological standpoints. These differences impact clinical features, diagnosis, and control of canine and feline parasites and transmission risk for humans. This review outlines the most common parasitoses and vector-borne diseases of dogs and cats, with a focus on major convergences and divergences, and discusses parasites that have (i) evolved based on different preys for dogs and cats, (ii) adapted due to different immunological or behavioral animal profiles, and (iii) developed more similarities than differences in canine and feline infections and associated diseases. Differences, similarities, and peculiarities of canine and feline parasitology are herein reviewed in three macrosections: (i) carnivorism, vegetarianism, anatomy, genetics, and parasites, (ii) evolutionary adaptation of nematodes, including veterinary reconsideration and zoonotic importance, and (iii) behavior and immune system driving ectoparasites and transmitted diseases. Emphasis is given to provide further steps toward a more accurate evaluation of canine and feline parasitology in a changing world in terms of public health relevance and One Health approach.

Case Reports of Cat Scratch Disease in Patient With Unjustified Surgical Intervention

Cat scratch disease (CSD) is often a rare and unrecognized illness, but it is important for practitioners to consider. CSD is commonly diagnosed in children, but adults may also get this disease. The manifestations of CSD can include the damage of internal organs, joints, eyes, heart, and kidneys. CSD should be included in the differential diagnoses of fever of unknown origin and any lymphadenopathy syndrome. For rheumatologists, this pathology is of interest due to the systemic involvement, as well as the disease debut from the musculoskeletal symptoms. We present a CSD clinical case of a patient whose disease began with an acute abdomen clinic, and after two months transformed into arthritis of the hand joints.

Clinical challenge - scratching the surface of the sheath

A 63-year-old white man with hypertension, hyperlipidemia, adrenal insufficiency, and history of metastatic spindle cell melanoma previously treated with ipilimumab, presented with unilateral papillitis in the left eye. The disc edema evolved to neuroretinitis with additional MRI findings of perineuritis. Broad laboratory evaluation confirmed active B. henselae infection, and he confirmed exposure to a newly adopted kitten. His vision improved following a course of antibiotics and oral steroids with resolution of clinical findings. To the best of our knowledge, this is the first reported case of cat-scratch neuroretinitis with MRI findings of optic nerve and optic nerve sheath enhancement.

Bartonella henselae is usually not viable in lymph nodes of patients with cat scratch disease

Bartonella henselae, the agent of cat scratch disease (CSD), appears to be a common organism responsible for lymphadenitis in both adults and children. There is a very low isolation rate for B. henselae from lymph nodes of patients with CSD. Our objective was to evaluate B. henselae viability in a large series of lymph nodes from patients with CSD. From January to November 2016, we analyzed lymph node biopsy samples from patients diagnosed with CSD. We used reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to detect B. henselae RNA, as well as cultures, histological analyses, and fluorescence in situ hybridization (FISH). We tested 87 lymph nodes positive for B. henselae DNA but only 8 (9%) presented with B. henselae RNA. We did not find a significant difference for the pap threshold cycle (C_T) values between RNA-positive and RNA-negative lymph nodes (p = 0.5). Cultures, histological analyses, and FISH were negative for all the tested samples. We provide evidence that B. henselae are not or are rarely viable in most cases in the lymph nodes of patients with CSD.

Isolation of Bartonella henselae and Two New Bartonella Subspecies, Bartonellakoehlerae Subspecies boulouisii subsp. nov. and Bartonella koehlerae Subspecies bothieri subsp. nov. from Free-Ranging Californian Mountain Lions and Bobcats

Domestic cats are the natural reservoir of Bartonella henselae, B. clarridgeiae and B. koehlerae. To determine the role of wild felids in the epidemiology of Bartonella infections, blood was collected from 14 free-ranging California mountain lions (Puma concolor) and 19 bobcats (Lynx rufus). Bartonella spp. were isolated from four (29%) mountain lions and seven (37%) bobcats. These isolates were characterized using growth characteristics, biochemical reactions, molecular techniques, including PCR-RFLP of selected genes or interspacer region, pulsed-field gel electrophoresis (PFGE), partial sequencing of several genes, and DNA-DNA hybridization. Two isolates were identical to B. henselae genotype II. All other isolates were distinguished from B. henselae and B. koehlerae by PCR-RFLP of the gltA gene using endonucleases HhaI, TaqI and AciI, with the latter two discriminating between the mountain lion and the bobcat isolates. These two novel isolates displayed specific PFGE profiles distinct from B. henselae, B. koehlerae and B. clarridgeiae. Sequences of amplified gene fragments from the three mountain lion and six bobcat isolates were closely related to, but distinct from, B. henselae and B. koehlerae. Finally, DNA-DNA hybridization studies demonstrated that the mountain lion and bobcat strains are most closely related to B. koehlerae. We propose naming the mountain lion isolates B. koehlerae subsp. boulouisii subsp. nov. (type strain: L-42-94), and the bobcat isolates B. koehlerae subsp. bothieri subsp. nov. (type strain: L-17-96), and to emend B. koehlerae as B. koehlerae subsp. koehlerae. The mode of transmission and the zoonotic potential of these new Bartonella subspecies remain to be determined.

Bacterial lymphadenitis at a major referral hospital in France from 2008 to 2012

Lymph node enlargement is a common medical problem, and in a large number of patients, the causes of lymphadenopathy remain undiagnosed. We report a thorough microbiological analysis of 1,688 lymph node biopsy specimens collected in our bartonellosis reference center. We studied lymph node biopsy samples from patients with suspected regional infectious lymph node enlargement from January 2008 to December 2012. To evaluate a useful strategy for the diagnosis of infectious lymphadenitis, specimens were cultured and subjected to molecular assays. Histologic analysis was done when possible. A total of 642 (38%) biopsy specimens were infected with a bacterial agent, and quantitative PCR (qPCR) was significantly better than 16S rRNA gene PCR (rrs) for the detection of Bartonella henselae (P = 0.05), Mycobacterium tuberculosis (P = 0.05), and Mycobacterium avium (P = 0.007). Molecular assays were significantly better than bacterial cultures for the diagnosis of Francisella tularensis (P = 0.017) but were less effective for detecting M. tuberculosis (P = 0.004) and M. avium (P = 0.001). Histologic analysis was done for 412 lymph nodes, and 20% of these were compatible with an infectious lymphadenitis, whereas a neoplasm was found in 29% of these lymph nodes. M. tuberculosis was detected significantly more in female than in male patients (P = 0.01), and patients with cat scratch disease (CSD) were younger than patients with M. tuberculosis, Tropheryma whipplei, and F. tularensis. Negative rrs PCR does not exclude the diagnosis of infectious lymphadenitis. Histologic analysis of lymph node biopsy specimens is critical, as a diagnosis of infectious lymphadenitis does not preclude other concurrent diseases.

Evidence of transfer by conjugation of type IV secretion system genes between Bartonella species and Rhizobium radiobacter in amoeba

Background

Bartonella species cospeciate with mammals and live within erythrocytes. Even in these specific niches, it has been recently suggested by bioinformatic analysis of full genome sequences that Lateral Gene Transfer (LGT) may occur but this has never been demonstrated biologically. Here we describe the sequence of the B. rattaustraliani (AUST/NH4^T) circular plasmid (pNH4) that encodes the tra cluster of the Type IV secretion system (T4SS) and we eventually provide evidence that Bartonella species may conjugate and exchange this plasmid inside amoeba.

Principal Findings

The T4SS of pNH4 is critical for intracellular viability of bacterial pathogens, exhibits bioinformatic evidence of LGT among bacteria living in phagocytic protists. For instance, 3 out of 4 T4SS encoding genes from pNH4 appear to be closely related to Rhizobiales, suggesting that gene exchange occurs between intracellular bacteria from mammals (bartonellae) and plants (Rhizobiales). We show that B. rattaustraliani and Rhizobium radiobacter both survived within the amoeba Acanthamoeba polyphaga and can conjugate together. Our findings further support the hypothesis that tra genes might also move into and out of bacterial communities by conjugation, which might be the primary means of genomic evolution for intracellular adaptation by cross-talk of interchangeable genes between Bartonella species and plant pathogens.

Conclusions

Based on this, we speculate that amoeba favor the transfer of genes as phagocytic protists, which allows for intraphagocytic survival and, as a consequence, promotes the creation of potential pathogenic organisms.

Skin diseases associated with Bartonella infection: facts and controversies

The genus Bartonella is composed of a series of species and subspecies. Ten of them are responsible for human infections. The best-identified diseases are cat scratch disease (B henselae and possibly B clarridgeiae), trench fever (B quintana), bacillary angiomatosis (B quintana and B henselae), and the spectrum of verruga peruana, Carrion disease, and Oroya fever (B bacilliformis). Controversies exist about the implication of a few other microorganisms being involved in these diseases. Several other conditions have been associated with the presence of Bartonella spp, but these observations await confirmation.

Zoonotic Bartonella species in fleas collected on gray foxes (Urocyon cinereoargenteus)

Bartonella spp. are fastidious, gram-negative, rod-shaped bacteria and are usually vector-borne. However, the vector has not been definitively identified for many recently described species. In northern California, gray foxes (Urocyon cinereoargenteus) are infected with two zoonotic Bartonella species, B. rochalimae and B. vinsonii subsp. berkhoffii. Fleas (range 1-8 fleas per fox) were collected from 22 (41.5%) of 54 gray foxes from urban and backcountry zones near Hoopa, California. The flea species were determined, and DNA was individually extracted to establish the Bartonella species harbored by these fleas. Of the 108 fleas collected, 99 (92%) were identified as Pulex simulans. Overall, 39% (42/108) of the fleas were polymerase chain reaction (PCR)-positive for Bartonella, with B. rochalimae and B. vinsonii subsp. berkhoffii identified in 34 (81%) and 8 (19%) of the PCR-positive fleas, respectively. There was no difference between the prevalence of Bartonella spp. in P. simulans for the urban and backcountry zones. Fourteen (64%) of the 22 foxes were Bartonella bacteremic at one or more of the capture dates. In 10 instances, both the foxes and the fleas collected from them at the same blood collection were Bartonella-positive. B. rochalimae was the predominant species identified in both foxes and fleas. The competency of Pulex fleas as a vector of B. rochalimae has not been confirmed and will need to be demonstrated experimentally. Pulex spp. fleas readily feed on humans and may represent a source of human exposure to zoonotic species of Bartonella.

Diagnostic microbiologique : du diagnostic par étiologie au diagnostic par syndrome

Objectifs

Depuis les dix dernières années, l’introduction de la biologie moléculaire et l’automatisation ont radicalement changé les pratiques dans les laboratoires de microbiologie clinique. L’amélioration de la communication entre les microbiologistes et les cliniciens ainsi que les évolutions technologiques telles que la standardisation et le développement de tests diagnostics plus rapides ont conduit à une réorganisation des laboratoires de microbiologie.

Méthodes

Jusqu’à présent la prescription des examens ciblait un diagnostic étiologique précis, actuellement l’évolution se fait vers le diagnostic par syndrome incluant un panel de tests regroupant les étiologies responsables d’un syndrome donné y compris les pathogènes émergents.

Résultats et conclusions

Dans cette revue, nous avons résumé les développements technologiques les plus récents en matière de diagnostic microbiologique adapté au diagnostic par syndrome incluant les stratégies de diagnostic exhaustif, les DNA microarray et les microarray antigéniques.

Infective endocarditis in a dog and the phylogenetic relationship of the associated "Bartonella rochalimae" strain with isolates from dogs, gray foxes, and a human

The first case of canine endocarditis caused by "Bartonella rochalimae" is reported. By PCR-restriction fragment length polymorphism, sequence, and phylogenetic analyses, Bartonella isolates from a dog with endocarditis, 22 gray foxes, and three dogs, described as B. clarridgeiae like, were confirmed to belong to the new species "B. rochalimae," suggesting canids as the natural reservoir.

Familial occurrence of cat-scratch disease, with varying clinical expression

Cat-scratch disease, primarily caused by Bartonella henselae, typically presents with regional adenopathy, and the role of antibiotics in the treatment is debatable. We present a report of B. henselae infection transmitted by the same kitten to 4 different individuals, each with different clinical characteristics, treatment, and evolution.

Gray foxes (Urocyon cinereoargenteus) as a potential reservoir of a Bartonella clarridgeiae-like bacterium and domestic dogs as part of a sentinel system for surveillance of zoonotic arthropod-borne pathogens in northern California

Two species of Bartonella, a novel Bartonella clarridgeiae-like bacterium and B. vinsonii subsp. berkhoffii, were isolated from rural dogs and gray foxes in northern California. A novel B. clarridgeiae-like species was isolated from 3 (1.7%) of 182 dogs and 22 (42%) of 53 gray foxes, while B. vinsonii subsp. berkhoffii was isolated from 1 dog (0.5%) and 5 gray foxes (9.4%). PCR and DNA sequence analyses of the citrate synthase (gltA) gene and the 16S-23S intergenic spacer region suggested that strains infecting dogs and gray foxes were identical. Fifty-four dogs (29%) and 48 gray foxes (89%) had reciprocal titers of antibodies against Bartonella spp. of > or =64. The high prevalence of bacteremia and seroreactivity to Bartonella spp. in gray foxes suggests that they may act as a reservoir species for the B. clarridgeiae-like species in this region. Domestic dogs were also tested for other arthropod-borne infectious agents. Fifty-one dogs (28%) were positive for Dirofilaria immitis antigen, seventy-four (40%) were seroreactive to Anaplasma phagocytophilum, and five (2.7%) were seropositive for Yersinia pestis. Fourteen dogs (7.6%) were PCR positive for A. phagocytophilum. Polytomous logistic regression models were used to assess the association of Bartonella antibody titer categories with potential risk factors and the presence of other vector-borne agents in domestic dogs. Older dogs were more likely to be seroreactive to Bartonella spp. There was no association between the exposure of dogs to Bartonella and the exposure of dogs to A. phagocytophilum in this study.

Adult systemic cat scratch disease associated with therapy for hepatitis C

Background

We describe the first case of systemic cat scratch disease in a patient receiving peginterferon α-2a and ribavirin for treatment of hepatitis C. Cases of adult systemic CSD are extremely infrequent and immunomodulatory treatment for hepatitis C has been associated with aberrant host responses to common pathogens.

Case presentation

A 52 year old man being treated for hepatitis C presented with diffuse lymphadenopathy, weight loss, fevers and splenic lesions. Symptoms were initially confused with adverse effects of his regimen, delaying recognition of his infection. Diagnostic investigation, including histopathology, microbiology and serologic parameters, confirmed that his illness was due to disseminated cat scratch disease with Bartonella henselae.

Conclusion

Disseminated CSD is exceptionally rare in adults. We describe the first case of disseminated cat scratch disease associated with peginterferon α and ribavirin to alert clinicians of the need to be aware of unusual manifestations of common infections in this population.

Lymph node biopsy specimens and diagnosis of cat-scratch disease

Histologic analysis of lymph node biopsy specimens may verify diagnosis of this disease.

We report microbiologic analysis of 786 lymph node biopsy specimens from patients with suspected cat-scratch disease (CSD). The specimens were examined by standard, cell culture, and molecular methods. Infectious agents were found in samples from 391 (49.7%) of 786 patients. The most commonly identified infectious agent was Bartonella henselae (245 patients, 31.2%), the agent of CSD. Mycobacteriosis was diagnosed in 54 patients (6.9%) by culture and retrospectively confirmed by using a specific real-time PCR assay. Neoplasm was diagnosed in 181 specimens suitable for histologic analysis (26.0%) from 47 patients. Moreover, 13 patients with confirmed Bartonella infections had concurrent mycobacteriosis (10 cases) or neoplasm (3 cases). A diagnosis of CSD does not eliminate a diagnosis of mycobacteriosis or neoplasm. Histologic analysis of lymph node biopsy specimens should be routinely performed because some patients might have a concurrent malignant disease or mycobacteriosis.

Bartonellosis: light and shadows in diagnostic and therapeutic issues

Cat-scratch disease involves a prolonged and/or complicated course, and lymph node drainage is usually required. Culture and molecular techniques often yield negative results, but immunofluorescence assays may give early information, and elevated antibodies may persist for months. Cat-scratch disease should be suspected in patients with prominent swelling of lymph nodes draining from the upper limbs, limited systemic involvement, and typical epidemiological-clinical features. The temporal antibody response during the sub-acute course remains unknown. Although biomolecular assays are available, the time between onset and investigation is an obstacle to positive results. The role of surgical debridement and the unpredictable activity of antimicrobial agents warrant further investigation.

A review of bacterial pathogens inCtenocephalides felisin New Zealand

The cat flea, Ctenocephalides felis, is the recognised vector of Bartonella henselae, B. clarridgeiae and Rickettsia felis. Although these Gram-negative bacteria were only described in the last decade, they are already known to cause a variety of diseases in people, particularly children and the immunosuppressed. Such diseases include cat-scratch disease, bacillary angiomatosis, endocarditis, bacteraemia, encephalopathy, neuroretinitis, osteomyelitis and peliosis hepatis. Although most infections in cats and dogs appear to be subclinical, recent studies have provided growing evidence that the bartonellas can also cause serious problems in pets, including hepatitis, endocarditis, central nervous system (CNS) signs, lymphadenopathy, uveitis, cataracts and reproductive failure. In 2004, DNA of B. henselae, B. clarridgeiae and R. felis was demonstrated in cat fleas from New Zealand and pets and their owners in the country are thus at risk of infection. While flea control programmes have traditionally been advocated by veterinarians to prevent pruritus and tapeworms in pets, they should now also be recommended to prevent infections with the new flea-borne bacterial pathogens. To raise awareness of the organisms amongst veterinarians and animal health workers, this review describes: the biology of the organisms; clinical and laboratory features of infections in cats, dogs and people; diagnosis; and possible treatments and control of infections with these organisms.