Tularemia in differential diagnosis of cervical lymphadenopathy: cytologic features of tularemia lymphadenitis

Causes of necrotic features in fine-needle aspirates from cervical lymph nodes

BACKGROUND

Lymph node fine-needle aspiration (LN FNA) cytology indicates necrosis in various diseases. Dominant necrotic features make the diagnosis of underlying conditions very difficult.

METHODS

We retrospectively reviewed 460 patients who underwent cervical LN aspiration cytology that revealed necrotic findings at Keimyung University Dongsan Hospital in Daegu, Korea, from 2003-2017. Each specimen was evaluated and analyzed in association with the clinical findings, biopsy findings, and/or other ancillary tests, including acid-fast bacilli staining and molecular testing for Mycobacterium tuberculosis.

RESULTS

When necrotic features were noted upon cervical LN FNA cytology, the most common pathologic LN FNA category was necrosis alone (31.5%). The second most common category was granulomatous inflammation (31.3%), followed by Kikuchi disease (20.0%) and malignant neoplasm (8.7%). In cases where the cervical LN FNA revealed necrosis alone, the most common final diagnosis was tuberculosis. In young patients, Kikuchi disease should be considered as one cervical LN FNA category, while metastatic carcinoma should be suspected in older patients.

CONCLUSIONS

Even when necrosis alone is observed in LN FNA cytology, it is important to determine the cause through further evaluation.

Pulmonary tularaemia: a differential diagnosis to lung cancer

Background

Pulmonary manifestations of tularaemia are reported to be infrequent in previous publications. During 2016, we noticed an increase in the number of hospitalised patients with pulmonary tularaemia in Eastern Norway. We aimed to investigate primary pulmonary tularaemia in Eastern Norway in terms of symptoms, radiological and microbiological findings, incidence and risk exposure.

Methods

A retrospective analysis of consecutive primary pulmonary tularaemia cases from 2016 until 2018 was conducted.

Results

From 1 September, 2016 until 31 December, 2018, 22 patients were diagnosed with primary pulmonary tularaemia at Innlandet Hospital Trust, representing 48% of all reported tularaemia cases in the region. A peak annual incidence of 3.4 in 100 000 was found in 2017.

All 22 patients lived in, or had recently visited, rural areas. Eighteen patients reported risk exposure for tularaemia, such as wood chopping, outdoor activities and farming prior to symptom onset. All patients experienced fever, and 19 patients had respiratory symptoms. Ten patients were in spontaneous recovery at diagnosis.

All patients had a chest computed tomography scan. Overall, 19 patients had pulmonary lesions and 18 had enlarged intrathoracic lymph nodes. The computed tomography images were described as suspicious of malignancy in 17 patients.

Conclusion

Pulmonary manifestations in tularaemia occurred more frequently in our region than expected from previous reports. Although all patients had symptoms consistent with infection, the majority were primarily investigated considering lung cancer due to the radiology report. In endemic areas, pulmonary tularaemia may be an important differential diagnosis to lung cancer.

Pulmonary tularaemia is possibly more frequent than previously reported. Due to similar radiological findings, pulmonary tularaemia may be an important differential diagnosis to lung cancer in endemic areas.https://bit.ly/2RcEPfN

A Practical Guide to the Role of Ancillary Techniques in the Diagnosis of Infectious Agents in Fine Needle Aspiration Samples

Fine needle aspiration samples and small biopsies provide a minimally invasive diagnostic modality for mass lesions. When an infectious process is suspected based on initial evaluation, ancillary techniques can assist in making a specific diagnosis. Here we review the cytopathology that should prompt additional testing and review the availability and interpretation of special stains, immunohistochemistry, and in situ hybridization. In addition, this review addresses when special cultures may be necessary and the use of newer molecular techniques for pathogen identification.

First report of Corynebacterium pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig (Sus scrofa domesticus)

BACKGROUND

Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis, a common disease in small ruminant populations throughout the world and responsible for a significant economic impact for producers.

CASE PRESENTATION

To our knowledge, this is the first characterization of C. pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig (Sus scrofa domesticus). In this study, phenotypic and genotypic identification methods allocated the swine isolates in C. pseudotuberculosis biovar ovis. The vast majority of the isolates were able to produce phospholipase D and were susceptible to most of the antimicrobial compounds tested. Macrorestriction patterns obtained by Pulsed Field Gel Electrophoresis (PFGE) grouped the C. pseudotuberculosis in two clusters with a high similarity index, which reveals their clonal relatedness. Furthermore, swine isolates were compared with C. pseudotuberculosis from caprines and PFGE patterns also showed high similarity, suggesting the prevalence of dominant clones and a potential cross-dissemination between these two animal hosts.

CONCLUSIONS

This work represents the first report of Corynebacterium pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig and alerts for the importance of the establishment of suitable control and sanitary management practices to control the infection and avoid further dissemination of this important pathogen to other animal hosts.