Pasteurella multocida lung and liver abscess in an immune-competent child

Pasteurella multocida bacteraemia with liver abscess

A previously healthy woman in her mid-70s presented with right upper quadrant abdominal pain, fever, intermittent chills and malaise for 1 week. She was clinically septic with raised inflammatory markers. Her blood culture revealed Pasteurella multocida, which was susceptible to penicillin and amoxicillin-clavulanic acid. CT of liver revealed an abscess of 8.0×7.9×8.5 cm at the left lobe of the liver. However, the abscess was not amenable for surgical or radiological drainage. She was a farmer and had close contact with her pet cats. She was occasionally scratched by her cats when caring for them. The liver abscess resolved completely without drainage after prolonged antimicrobial therapy of 109 days. She commenced on 63 days of intravenous antimicrobials and 46 days of oral amoxicillin-clavulanic acid. This case illustrated P. multocida bacteraemia with a large liver abscess in an immunocompetent adult after non-bite exposure.

Liver microbial community and associated host transcriptome in calves with feed induced acidosis

Introduction

In the dairy industry, calves are typically fed diets rich in highly fermentable carbohydrates and low in fibrous feeds to maximize ruminal papillae and tissue development. Calves on such diets are vulnerable at developing ruminal acidosis. Prevalent in cattle, liver abscess (LA) is considered a sequela to ruminal acidosis. LAs can cause significant liver function condemnation and decreased growth and production. Currently, we know little about the liver microbiome in calves with feed-induced acidosis.

Methods

Using our established model of ruminal acidosis, where young calves were fed an acidosis-inducing (AC) or -blunting (control) diet starting at birth until 17-week of age, we investigated microbial community changes in the liver resultant from ruminal acidosis. Eight calves were randomly assigned to each diet, with four animals per treatment. Rumen epithelium and liver tissues were collected at 17 weeks of age right after euthanasia. Total RNAs were extracted and followed by whole transcriptome sequencing. Microbial RNA reads were enriched bioinformatically and used for microbial taxonomy classification using Kraken2.

Results

AC Calves showed significantly less weight gain over the course of the experiment, in addition to significantly lower ruminal pH, and rumen degradation comparison to the control group (p < 0.05). In the liver, a total of 29 genera showed a significant (p < 0.05) abundance change (> 2-fold) between the treatments at 17-week of age. Among these, Fibrobacter, Treponema, Lactobacillus, and Olsenella have been reported in abscessed liver in cattle. Concurrent abundance changes in 9 of the genera were observed in both the liver and rumen tissues collected at 17-week of age, indicating potential crosstalk between the liver and rumen epithelial microbial communities. Significant association was identified between host liver gene and its embedded microbial taxa. Aside from identifying previously reported microbial taxa in cattle abscessed liver, new repertoire of actively transcribed microbial taxa was identified in this study.

Discussion

By employing metatranscriptome sequencing, our study painted a picture of liver microbiome in young calves with or without feed induced acidosis. Our study suggested that liver microbiome may have a critical impact on host liver physiology. Novel findings of this study emphasize the need for further in-depth analysis to uncover the functional roles of liver resident microbiome in liver metabolic acidosis resultant from feed-related ruminal acidosis.

A Rare Case of Glossitis due to Pasteurella multocida after a Cat Scratch

Pasteurella is one of the zoonotic pathogens that can cause variety of serious infections in animals and humans such as bacteremia, septic shock, endocarditis, meningitis, prosthetic and native valve infections, osteomyelitis, skin and soft tissue infections, abscesses, and even pneumonia with empyema. However, there have been few reports of upper respiratory involvements like tonsillitis and epiglottitis in humans. We present a case of recurrent Pasteurella glossitis after a cat scratch which has not been reported in humans.

[Systemic granulomatosis of infectious origin]

PURPOSE

Granulomatous diseases are defined by specific histological features, following the local recruitment of macrophages and lymphocytes. Many infections can lead to the development of granuloma.

CURRENT KNOWLEDGE AND KEY POINTS

Microorganisms responsible for granuloma include mainly mycobacteria, many viral and fungal species, as well as schistosoma in endemic areas. Nevertheless, almost all microorganisms can lead to granuloma, especially if their clearance needs macrophages pathway. New immunosuppressive drugs such as tumor necrosis factor antagonists are associated with a high risk of infectious granulomatous complications. All patients with granuloma must be carefully screened to find a potential underlying infection, since an immunosuppressive therapy could be otherwise considered. We here review the general diagnostic process with a specific glance to the main organs.

FUTURE PROSPECTS AND PROJECTS

Without clinical or epidemiological clue, diagnosis can be very tedious. New molecular tools now assist classical microbiological and histological techniques. Their specificity and sensitivity have recently been better characterized, and their use will probably increase in the near future for the diagnosis of infectious granuloma. They may also lead to discover new infectious aetiologies of granulomatous diseases formerly considered as idiopathic. We describe here the main microorganisms that can be responsible for granuloma, with a specific focus on the use of new diagnostic tools.

Microbiological diagnostic procedures in respiratory infections: suppurative lung disease

Pursuing a microbiological diagnosis in suppurative lung disease can enable focused antibiotic therapy, identify pathogens of potential concern for infection control, and in some cases delineate a specific pathological process. Suppurative lung disease can be categorized as acute or chronic. Acute disease most commonly consists of lung abscess or parapneumonic empyema. The vast majority of chronic suppurative lung disease in childhood is due to cystic fibrosis. Samples from the respiratory tract offer the most useful information for diagnosis and management, but adjunctive information can also be obtained from serological methods, blood cultures and molecular techniques. The quality of respiratory tract samples is vital to aid accurate interpretation of results, and this varies according to the technique of collection. Antibiotic sensitivity testing is of particular importance in an era of evolving antibiotic resistance and can be problematical in cystic fibrosis.