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

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.

Concurrence of cat-scratch disease and paradoxical tuberculosis-IRIS lymphadenopathy: a case report

BACKGROUND

Mycobacterial infections can cause significant morbidity when cellular immunity is compromised. Patients with AIDS can be affected directly from infection or through mycobacterial IRIS, especially if they are previously untreated for HIV. Herein a case of tuberculous lymphadenitis is reported, which primarily responded to antimicrobials but complicated by IRIS and cat-scratch disease at a later course.

CASE PRESENTATION

A 23-year-old man, intravenous drug user with untreated HIV and HCV infection presented with fever and painful cervical lymphadenopathy. Mycobacterium tuberculosis was isolated from PCR and culture of ultrasound-guided lymph node aspirate and a four-drug anti-TB regimen was subsequently administered, leading to complete resolution of clinical and laboratory abnormalities. Given the patient's CD4 count (67 cells per mm³), antiretroviral treatment started seven weeks after TB treatment initiation. Within the first month of ART fever recurred along with cervical lymph node inflammation. Paradoxical IRIS was considered as the most probable diagnosis but workup expanded, revealing acute Bartonella infection. A posteriori, the patient remembered being scratched by a stray cat two weeks before his new symptoms started. Doxycycline and corticosteroid monotherapy failed to resolve symptoms, whereas a combination of doxycycline for 3 months and methylprednisolone with long-term tapering led to negative follow-up Bartonella antibodies and complete clinical and biochemical response, without recurrence.

CONCLUSIONS

Co-infection with TB and Bartonella presenting with lymphadenitis is unusual. Cat-scratch disease can be a rare clinical presentation of Bartonella infection in patients with AIDS, but coexistence of bartonellosis and paradoxical IRIS has never been reported before. However, physicians treating people living with HIV should be aware of this potential concurrence. Early testing for Bartonella infection could be offered in patients with TB and HIV co-infection in case of acute deterioration or partial response to treatment, especially if they have a history of cat exposure, since clinical picture can be indistinguishable.

Prevalence and Predictors of Bacterial Contamination in Excisional Lymph Node Biopsies: Implications for Diagnosis and Management

Routine tissue handling exposes lymph node specimens to microbial contamination that can confound microbiological culture results and interfere with diagnosis. The scope and impact of this problem remain poorly understood. We combined over 13 years of lymph node pathology, culture data, and patient records to define the prevalence, predisposing factors, microbiology, and clinical management of false-positive lymph node cultures at a large academic medical center. Nearly one third (31.9%) of 216 cultured lymph nodes yielded bacterial growth. Approximately 90% of positive bacterial cultures grew 1 of 2 common skin-resident taxa-coagulase-negative Staphylococcus and Cutibacterium acnes-with well-documented predispositions for contamination in other clinical settings. Lymph nodes excised from axillary, cervical, and inguinal regions yielded higher positive culture rates than nodes excised from the mediastinum, suggesting proximity to the skin surface may increase contamination risk. Accordingly, cultures from thoracoscopic pulmonary resections displayed contamination rates over 5-fold lower than those from percutaneously accessed lymph nodes. Lymph nodal tissue allocated for culture in the operating room yielded unexpectedly high contamination rates, significantly higher than cultures sent from the frozen section processing area. A significant minority of contamination events were noted in the clinical record and prompted antibiotic therapy on multiple occasions. Collectively, our results illuminate the risk factors contributing to bacterial contamination and argue that routine lymph node bacterial cultures provide minimal clinical benefit for adult patients. This widespread bacterial contamination also warrants cautious implementation of increasingly sensitive molecular microbiology tools for excised tissues.

Head and Neck Masses

Head and neck cancers comprise 4% of the cancer burden in the United States each year. Many types of head and neck cancers present as an asymptomatic, nontender neck mass or nonspecific symptoms, such as hoarseness, sore throat, and pain. Head and neck cancers are frequently diagnosed incidentally by the primary care physician or dentist. This review summarizes the epidemiology, clinical manifestations, diagnosis, and treatment of several common head and neck cancers in order to provide an increased awareness for the internist to facilitate early detection of these diseases.

Repertoire of the gut microbiota from stomach to colon using culturomics and next-generation sequencing

BACKGROUND

Most studies on the human microbiota have analyzed stool samples, although a large proportion of the absorption of nutrients takes place in upper gut tract. We collected samples from different locations along the entire gastrointestinal tract from six patients who had simultaneously undergone upper endoscopy and colonoscopy, to perform a comprehensive analysis using culturomics with matrix assisted laser desorption ionisation - time of flight (MALDI-TOF) identification and by metagenomics targeting the 16S ribosomal ribonucleic acid (rRNA) gene.

RESULTS

Using culturomics, we isolated 368 different bacterial species, including 37 new species. Fewer species were isolated in the upper gut: 110 in the stomach and 106 in the duodenum, while 235 were isolated from the left colon (p < 0.02). We isolated fewer aero-intolerant species in the upper gut: 37 from the stomach and 150 from the left colon (p < 0.004). Using metagenomics, 1,021 species were identified. The upper gut microbiota was revealed to be less rich than the lower gut microbiota, with 37,622 reads from the stomach, 28,390 from the duodenum, and 79,047 from the left colon (p < 0.009). There were fewer reads for aero-intolerant species in the upper gut (8,656 in the stomach, 5,188 in the duodenum and 72,262 in the left colon, p < 0.02). Patients taking proton pump inhibitors (PPI) were then revealed to have a higher stomach pH and a greater diversity of species in the upper digestive tract than patients not receiving treatment (p < 0.001).

CONCLUSION

Significant modifications in bacterial composition and diversity exist throughout the gastrointestinal tract. We suggest that the upper gut may be key to understanding the relationship between the gut microbiota and health.

Bartonella henselae infection in diverse clinical conditions in a tertiary care hospital in north India

Background & objectives:

Bartonella henselae causes infections which closely resemble febrile illness and chronic diseases such as tuberculosis and haematological malignancies. There are not many studies on Bartonella infections from India. The present study was undertaken to diagnose B. henselae infection in diverse clinical conditions in a tertiary care hospital in north India.

Methods:

A total of 145 patients including those with fever and lymphadenopathy, infective endocarditis and neuroretinitis were enrolled in the study. Whole blood, serum and lymph node aspirate and valvular vegetations if available, were obtained. Samples were plated on chocolate agar and brain-heart infusion agar containing five per cent fresh rabbit blood and were incubated at 35°C for at least four weeks in five per cent CO₂ with high humidity. Immunofluorescent antibody assay (IFA) was done for the detection of IgM antibodies in the serum using a commercial kit. Whole blood was used to perform polymerase chain reaction (PCR) for the citrate synthase gene (gltA).

Results:

IFA was positive in 11 of 140 (7.85%) patients and PCR was positive in 3 of 140 (2.14%) patients. Culture was negative in all the cases. A higher incidence of Bartonella infection was seen in patients with fever and lymphadenopathy (n=30), seven of whom were children. In ophthalmological conditions, four cases were IFA positive.

Interpretation & conclusions:

The present study shows that the threat of Bartonella infection is a reality in India. It is also an important treatable cause of fever and lymphadenopathy in children. Serology and PCR are useful tests for its diagnosis. Clinicians should consider Bartonella infection in the differential diagnosis of febrile illnesses and chronic diseases.

Seek and Find! PCR analyses of skin infections in West-European travelers returning from abroad with an eschar

BACKGROUND

Skin infections are among the leading causes of diseases in travelers. Diagnosing pathogens could be difficult.

METHOD

We applied molecular assays for the diagnostic of a large collection of skin biopsies and swabs from travelers with suspected skin infections. All samples were tested by qPCR for Coxiella burnetti, Bartonella sp., Rickettsia sp., Borrelia sp., Ehrlichia sp., Tropheryma whipplei, Francisella tularensis, Mycobacteria sp., Staphylococcus aureus, Streptococcus pyogenes, Leishmania spp., Ortho poxvirus and Para poxvirus and then screened for the presence of bacteria by PCR amplification and sequencing, targeting the 16S rRNA gene.

RESULTS

From January 2009 to January 2017, 100 international travelers presenting with a suspected skin infection were enrolled. We detected 51 patients with an identified pathogen on skin samples. Travelers presenting with eschars were more likely to have a positive PCR sample (n = 44/76, 57.9%) compared to other patients (n = 7/24, 29.2%). Spotted fever group Rickettsia (n = 28) was the most frequently detected pathogens (19 R. africae, 6 R. conorii, 3 R. mongolitimonae); S. aureus were detected in 11 patients; S. pyogenes in 3; Leishmania sp.; M. leprae and B. henselae in 1 patient, respectively.

CONCLUSION

By targeting the most commonly encountered causative agents of travel-related skin infections, our strategy provides a sensitive and rapid diagnostic method.

Case Report: Scalp Eschar and Neck Lymphadenopathy Associated with Bacteremia due to Coxiella-Like Bacteria

Coxiella-like bacteria have been recently proposed as human pathogens. Using molecular techniques, we detected Coxiella-like bacteria in the blood and serum samples of a patient with a scalp eschar, neck lymphadenopathy, severe urticaria, edema, fever, and arthralgia indicating that this organism can provide systemic complications.

Carcinoma of Maxillary Gingiva with Non-specific Cervical Lymph Node Swelling

Swelling of the cervical lymph nodes may indicate lymphadenitis, malignant lymphoma, or metastasis. Lymph nodes larger than 10 mm on computed tomography (CT) are strongly indicative of postoperative metastasis from carcinoma. Here, we report a case of large, inflamed lymph nodes mimicking metastasis. The patient was a 76-year-old woman who experienced discomfort in the left-side maxillary gingiva commencing in August 2011. By September, the area had become painful, causing her to visit the Tokyo Dental College Chiba Hospital, at which time a 75×50-mm swollen ulcer was observed in the maxillary gingiva on the left side. A CT image revealed a neoplastic lesion between the alveolar bone on the left side of the maxilla and the base of the maxillary sinus, together with evidence of osteoclastic activity. The bilateral cervical lymph nodes were Level II and had a uniform interior of approximately 5 mm. The lesion was subsequently excised under general anesthesia. At 34 days postoperatively, CT imaging revealed bilateral 40-mm internal heterogeneous lymphadenopathy at Level II. No inflammation of the maxillary gingiva was observed, however, and blood tests revealed no inflammatory findings. Bilateral cervical lymph node metastasis was diagnosed based on CT and oral cavity observation. Radical neck dissection of left cervical region was performed under general anesthesia. Histopathological examination of the lymph nodes revealed no metastasis at Levels I-V, however. The reason for this increase in lymph node size is discussed.

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.

'Arthrobacter saudimassiliensis' sp. nov. a new bacterial species isolated from air samples in the urban environment of Makkah, Saudi Arabia

We report here the main characteristics of ‘Arthrobacter saudimassiliensis’ strain 11W110_air^T (CSUR P1223), a new species of the Arthrobacter genus that was isolated from air samples in the city environment of Makkah, Saudi Arabia, during the pilgrim period of Hajj 2012.

'Lysinibacillus saudimassiliensis' sp. nov., a new bacterial species isolated from air samples in the urban environment of Makkah, Saudi Arabia

We report here the main characteristics of 'Lysinibacillus saudimassiliensis' strain 13S34_air^τ (CSUR = P1222), a new species of the Lysinibacillus genus that was isolated from air samples in the city environment of Makkah, Saudi Arabia, during the pilgrim period of Hajj 2012.

'Pseudomonas saudimassiliensis' sp. nov. a new bacterial species isolated from air samples in the urban environment of Makkah, Saudi Arabia

We report here the main characteristics of ‘Pseudomonas saudimassiliensis’ strain 12M76_air^T (CSUR P1220), a new species of the Pseudomonas genus that was isolated from air samples in the city environment of Makkah, Saudi Arabia, during the pilgrim period of Hajj 2012.

'Halomonas saudii' sp. nov., a new bacterial species isolated from marine plant Halocnemum strobilaceum

We report here the main characteristics of 'Halomonas saudii' strain Saudii DR2 (CSUR P2512), a new species of the Halomonas genus that was isolated from a rhizosphere of Halocnemum strobilaceum in April 2015.

'Pseudomonas saudiphocaensis' sp. nov., a new bacterial species isolated from currency notes collected during the Hajj pilgrimage in 2012 at Makkah, Saudi Arabia

We report here the main characteristics of ‘Pseudomonas saudiphocaensis’ strain 20_BN^T (CSUR P1224), a new species of the Pseudomonas genus that was isolated from currency notes collected during the Hajj pilgrimage in 2012 at Makkah, Saudi Arabia.

'Jeotgalicoccus saudimassiliensis' sp. nov., a new bacterial species isolated from air samples in the urban environment of Makkah, Saudi Arabia

We report here the main characteristics of ‘Jeotgalicoccus saudimassiliensis’ strain 13MG44_air^T (CSUR P1221), a new species of the Jeotgalicoccus genus that was isolated from air samples in the city environment of Makkah, Saudi Arabia, during the pilgrim period of Hajj 2012.

Candidatus Coxiella massiliensis Infection

Bacteria genetically related to Coxiella burnetii have been found in ticks. Using molecular techniques, we detected Coxiella-like bacteria, here named Candidatus Coxiella massiliensis, in skin biopsy samples and ticks removed from patients with an eschar. This organism may be a common agent of scalp eschar and neck lymphadenopathy after tick bite.

Marseillevirus in lymphoma: a giant in the lymph node

The family Marseilleviridae is a new clade of giant viruses whose original member, marseillevirus, was described in 2009. These viruses were isolated using Acanthamoeba spp primarily from the environment. Subsequently, a close relative of marseillevirus was isolated from the faeces of a healthy young man, and others were detected in blood samples of blood donors and recipients and in a child with lymph node adenitis. In this Grand Round we describe the detection of marseillevirus by PCR, fluorescence in-situ hybridisation, direct immunofluorescence, and immunohistochemistry in the lymph node of a 30-year-old woman diagnosed with Hodgkin's lymphoma, together with IgG antibodies to marseillevirus. A link with viruses and bacteria has been reported for many lymphomas. We review the literature describing these associations, the criteria used to consider a causal association, and the underlying mechanisms of lymphomagenesis. Our observations suggest that consideration should be given to marseillevirus infections as an additional viral cause or consequence of Hodgkin's lymphoma, and that this hypothesis should be tested further.

What to expect from molecular tools for non-documented pediatric infectious diseases

OBJECTIVE

Evaluation of the contribution of molecular tools to the overall diagnosis of infectious diseases in children.

METHODS

Results of 16S rDNA analysis (179 children; 228 specimens), combined to specific amplification of Kingella kingae (126 children; 166 osteoarticular specimens), were retrospectively analyzed for samples with inconclusive cultures.

RESULT

The overall positive yield in diagnosis was 12.8% of the patients for 16S rDNA PCR, 40.5% for K. kingae PCR and 45.2% for combined use of both methods. Results were related to clinical and biological data (direct examination, certainty/uncertainty of clinical diagnosis, fever, biological markers, previous antibiotics), and to the number of samples analyzed per patient, allowing the identification of specific situations with significant contribution of PCR methods.

CONCLUSION

Molecular techniques constitute valuable tools to improve the bacterial infection diagnosis in children; however, specific indications, dedicated samples, and number of analyzed samples per patient are key points to optimize their contribution.

Blood-Borne Candidatus Borrelia algerica in a Patient with Prolonged Fever in Oran, Algeria

To improve the knowledge base of Borrelia in north Africa, we tested 257 blood samples collected from febrile patients in Oran, Algeria, between January and December 2012 for Borrelia species using flagellin gene polymerase chain reaction sequencing. A sequence indicative of a new Borrelia sp. named Candidatus Borrelia algerica was detected in one blood sample. Further multispacer sequence typing indicated this Borrelia sp. had 97% similarity with Borrelia crocidurae, Borrelia duttonii, and Borrelia recurrentis. In silico comparison of Candidatus B. algerica spacer sequences with those of Borrelia hispanica and Borrelia garinii revealed 94% and 89% similarity, respectively. Candidatus B. algerica is a new relapsing fever Borrelia sp. detected in Oran. Further studies may help predict its epidemiological importance.

[Diagnosis of infectious lymphadenitis]

Adenitis is a common disorder requesting numerous medical specialties. Etiologies are dominated by viral and bacterial infections, and more rarely parasitic, or by neoplastic and inflammatory diseases. Nevertheless, etiology remains often unknown and invasive tests may be required. On nodal tissue sample, histological examination, culture and polymerase chain reaction (PCR) are realized. PCR has revolutionized the diagnostic approach and consequently, knowledge of infectious lymphadenopathy. Previously, staphylococcus, streptococcus and mycobacterium were the main infectious agents identified in lymph nodes. Since its use, new emergent microorganisms responsible of lymphadenitis have been identified. Bartonella henselae, responsible of cat scratch disease, is to date the infectious agent most often encountered in adenitis. Mycobacterium avium subsp. hominisuis has been recently described as responsible of children lymphadenitis. PCR has become an essential tool in the diagnostic process of infectious lymphadenitis. Here, we propose a literature review on infectious adenitis and we emphasize the diagnostic strategy of adenitis.

Positron emission tomography in the diagnosis of Whipple's endocarditis: a case report

BACKGROUND

Whipple's disease is a systemic infection that sometimes is associated with cardiac manifestations. The diagnosis of Tropheryma whipplei endocarditis is still the result of chance because there are no diagnostic criteria and clinical signs are often those of cardiac disease rather than infection.

CASE PRESENTATION

Culture-negative endocarditis was suspected in a non-febrile 77-year-old French woman from North France with a history of a graft replacement 4 years prior. Positron emission tomography revealed intense fluorodeoxyglucose uptake around the metal ring of the aortic graft. The valve was replaced, and T. whipplei was detected in a valve sample by molecular assays. Immunohistochemical staining of the valve for T. whipplei was also positive.

CONCLUSION

The localization of infectious foci by positron emission tomography and systematically testing valve specimens for T. whipplei are promising for diagnosing Whipple's disease.

[Histopathological study of cervical lymphadenopathy in Yaounde, Cameroon]

Introduction

Les adénopathies cervicales ont été très peu étudiées au Cameroun.

Méthodes

Pour améliorer leur connaissance nous avons mené une étude rétrospective et descriptive dans les cinq principaux laboratoires de la capitale du pays en vue d'en déterminer les aspects histopathologiques.

Résultats

Nous avons colligé 292 cas. L’âge moyen était de 30,95 ±4,11ans et le ratio homme / femme était de 0,96/1. Les principaux diagnostics histologiques étaient les suivants: tuberculose ganglionnaire (39,38%), les lymphadénites (18,49%), les lymphomes malins non hodgkiniens (12,33%), la maladie de Kaposi ganglionnaire (5,82%), les métastases de carcinome (5,82%) et la maladie de Hodgkin (5,14%). Dans 95,65% des cas le diagnostic était posé au-delà du deuxième mois d’évolution des symptômes.

Conclusion

Nos résultats, quoique préliminaires, sont une contribution à l'amélioration de la stratégie diagnostique et thérapeutique dans nos hôpitaux aux ressources limitées.

Coxiella burnetii-positive PCR in febrile patients in rural and urban Africa

OBJECTIVES

Q fever has been reported throughout the African continent. The objective of this study was to detect the presence of Coxiella burnetii in febrile patients from Africa.

METHODS

Blood samples from febrile and non-febrile patients from six African countries and from France were investigated retrospectively for Q fever infection by molecular assays targeting the IS1111 and IS30A spacers.

RESULTS

We tested 1888 febrile patients from Senegal, Mali, Tunisia, Algeria, Gabon, and Morocco and found one male adult patient (0.3%) infected with C. burnetii in Algeria and six positive patients (0.5%) in Senegal. For one patient from Senegal we determined that the infection was caused by C. burnetii genotype 35. In Senegal, more patients were infected with C. burnetii in Keur Momar Sarr (p=0.002) than in the other locations. Blood samples taken from 500 (51% males) non-febrile people from Senegal and France were all negative.

CONCLUSIONS

The installation of point-of-care laboratories in rural Africa can be a very effective tool for studying the epidemiology of many infectious diseases.

Methods for the discovery of emerging pathogens

Recently, there has been a steady increase in the number of recognized pathogenic microorganisms, specifically bacteria. The development of genetic technologies, MALDI-TOF mass spectrometry and new culturing techniques has significantly widened the repertoire of known microorganisms and therefore pathogenic microorganisms. The repertoire of infectious agents has been studied in various environments including water, soil, pets, livestock, wildlife and arthropods. Using different methods, many known pathogens can be identified in these samples; therefore, the impact of emergent pathogens on humans can be examined and novel pathogens can be identified. In this special issue, we discuss the identification of emerging pathogens in the environment and animals.

Infectious lymphadenitis in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma: a rare, but important, complication

The differential diagnosis of rapidly progressive or symptomatic lymphadenopathy in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) includes infectious lymphadenitis. We studied 286 (9%) of 3040 patients with CLL seen between 2003 and 2012 at Mayo Clinic Rochester who had 356 diagnostic lymph node biopsies to evaluate rapidly progressive or symptomatic lymphadenopathy. Most (85.4%) biopsies showed progressive CLL, 8.9% a second lymphoid malignancy, 3.9% infectious lymphadenitis, 1.1% reactive adenitis and 0.6% non-hematological malignancies. Of the 12 patients (14 biopsies) with infectious lymphadenitis, five patients had never been treated for their CLL, and seven had a specific microbiological diagnosis (herpes simplex n=3, Cryptococcus neoformans n=1, Mycobacterium n=1, coagulase negative Staphylococcus n=2). We conclude that infectious lymphadenitis is a rare complication of CLL with clinical characteristics similar to progressive CLL and transformation to a more aggressive lymphoma. Early recognition and antimicrobial therapy treatment of infectious lymphadenitis can be highly effective in these patients.