Bartonella henselae is usually not viable in lymph nodes of 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.

Cat Scratch Disease with Generalized Bone Lesions in an Immunocompetent Child

A 9-year-old immunocompetent girl with prolonged fever for 1 month was suspected of having a malignancy because of generalized bone abnormalities identified by MRI. Histopathology of liver tissues indicated the diagnosis of cat-scratch disease (CSD). Results of NGS, immunofluorescence and immunochemical assay confirmed the causative agent was Bartonella henselae. Paediatricians should increase their awareness of CSD as a cause for bone lesions, except for malignancy.

A preliminary investigation into bacterial viability using scanning electron microscopy–energy-dispersive X-ray analysis: The case of antibiotics

The metabolic stages of bacterial development and viability under different stress conditions induced by disinfection, chemical treatments, temperature, or atmospheric changes have been thoroughly investigated. Here, we aim to evaluate early metabolic modifications in bacteria following induced stress, resulting in alterations to bacterial metabolism. A protocol was optimized for bacterial preparation using energy-dispersive X-ray (EDX) microanalysis coupled with scanning electron microscopy (SEM), followed by optimizing EDX data acquisition and analysis. We investigated different preparation methods aiming to detect modifications in the bacterial chemical composition at different states. We first investigated Escherichia coli, acquiring data from fresh bacteria, after heat shock, and after contact with 70% ethanol, in order to prove the feasibility of this new strategy. We then applied the new method to different bacterial species following 1 h of incubation with increasing doses of antibiotics used as a stress-inducing agent. Among the different materials tested aiming to avoiding interaction with bacterial metabolites, phosphorous-doped silicon wafers were selected for the slide preparation. The 15 kV acceleration voltage ensured all the chemical elements of interest were excited. A thick layer of bacterial culture was deposited on the silicon wafer providing information from multiple cells and intra-cellular composition. The EDX spectra of fresh, heat-killed, and alcohol-killed E. coli revealed important modifications in magnesium, potassium, and sodium. Those same alterations were detected when applying this strategy to bacteria exposed to antibiotics. Tests based on SEM–EDX acquisition systems would provide early predictions of the bacterial viability state in different conditions, yielding earlier results than culture.

[Bone involvement in cat scratch disease]

INTRODUCTION

Cat scratch disease caused by Bartonella henselae with bone involvement is a rare presentation.

CASE REPORT

We report a case of disseminated bartonellosis with multifocal osteomyelitis and multiple visceral involvement in an immunocompetent adult. Diagnostic confirmation was obtained by PCR on lymphadenopathy. In addition to our observation, 31 cases of bartonellosis with bone involvement were reported in the literature. Diagnosis is based on a combination of history, serology and PCR performed on tissue. The antibiotic treatment allows recovery in all cases.

CONCLUSION

Cat scratch disease in its systemic form with bone involvement is a rare and difficult diagnosis for the clinician and an invasive approach is often required to obtain the diagnosis.

Cat Scratch Disease and Bartonellaceae: The Known, the Unknown and the Curious

Since the early 1900s, Bartonella species were known only to cause human disease resulting from very restricted geographic (bartonellosis) or environmental influences ("trench fever"). In the 1990s, and in parallel, cat scratch disease and bacillary angiomatosis were definitively linked to Bartonella species. Subsequently, widespread use of modern diagnostic methods revealed the broad ecologic niche of this organism and greatly expanded our knowledge of the epidemiology and clinical presentations associated with this genus. A large number of reservoirs and vectors involved with Bartonella propagation and transmission to humans have been identified; cats and various arthropods remain the most well-studied to date. Though not completely understood, it appears that specific immune-modulated interactions between the infecting species and host-related factors play a major role in the observed breadth of human clinical syndromes associated with Bartonellae, the large differences in immunopathologic features of tissue samples among different syndromes and potentially the varied responses to antimicrobial therapy. Further, the clinical management for cat scratch disease in particular is quite variable among clinicians, reflecting a poor evidence base. No preventive measures have been developed beyond suggestions to avoid at-risk behavior with known vectors.

Cystic form of cervical lymphadenopathy. Guidelines of the French Society of Otorhinolaryngology - Head and Neck Surgery (SFORL). Part 1: Diagnostic procedures for lymphadenopathy in case of cervical mass with cystic aspect

OBJECTIVES

The authors present the guidelines of the French Society of Otorhinolaryngology - Head and Neck Surgery Society on diagnostic procedures for lymphadenopathy in case of a cervical mass with cystic aspect.

METHODS

A multidisciplinary work-group was entrusted with a review of the scientific literature on the topic. Guidelines were drawn up, then read over by an editorial group independent of the work-group, and the final version was drawn up. Guidelines were graded as A, B, C or expert opinion, by decreasing level of evidence.

RESULTS

In adults presenting a cystic cervical mass, it is recommended to suspect cervical lymphadenopathy: in order of decreasing frequency, cystic metastasis of head and neck squamous cell carcinoma, of undifferentiated nasopharyngeal carcinoma, and of thyroid papillary carcinoma (Grade C). On discovery of a cystic cervical mass on ultrasound, architectural elements indicating a lymph node and a thyroid nodule with signs of malignancy should be screened for, especially if the mass is located in levels III, IV or VI (Grade A). Malignant lymphadenopathy should be suspected in case of cervical mass with cystic component on CT (Grade B), but benign or malignant status cannot be diagnosed only on radiological data (CT or MRI) (Grade A), and 18-FDG PET-CT should be performed, particularly in case of inconclusive ultrasound-guided fine needle aspiration biopsy (Grade C).

Fluorescence In Situ Hybridization (FISH) and Peptide Nucleic Acid Probe-Based FISH for Diagnosis of Q Fever Endocarditis and Vascular Infections

Endocarditis and vascular infections are common manifestations of persistent localized infection due to Coxiella burnetii, and recently, fluorescence in situ hybridization (FISH) was proposed as an alternative tool for their diagnosis. In this study, we evaluated the efficiency of FISH in a series of valve and vascular samples infected by C. burnetii We tested 23 C. burnetii-positive valves and thrombus samples obtained from patients with Q fever endocarditis. Seven aneurysms and thrombus specimens were retrieved from patients with Q fever vascular infections. Samples were analyzed by culture, immunochemistry, and FISH with oligonucleotide and PNA probes targeting C. burnetii-specific 16S rRNA sequences. The immunohistochemical analysis was positive for five (17%) samples with significantly more copies of C. burnetii DNA than the negative ones (P = 0.02). FISH was positive for 13 (43%) samples and presented 43% and 40% sensitivity compared to that for quantitative PCR (qPCR) and culture, respectively. PNA FISH detected C. burnetii in 18 (60%) samples and presented 60% and 55% sensitivity compared to that for qPCR and culture, respectively. Immunohistochemistry had 38% and 28% sensitivity compared to that for FISH and PNA FISH, respectively. Samples found positive by both immunohistochemistry and PNA FISH contained significantly more copies of C. burnetii DNA than the negative ones (P = 0.03). Finally, PNA FISH was more sensitive than FISH (60% versus 43%, respectively) for the detection of C. burnetii We provide evidence that PNA FISH and FISH are important assays for the diagnosis of C. burnetii endocarditis and vascular infections.