Isolation of Yersinia pseudotuberculosis serotype V from the blood of a patient with sickle-cell anaemia

Effects of urbanization on host-pathogen interactions, using Yersinia in house sparrows as a model

Urbanization strongly affects biodiversity, altering natural communities and often leading to a reduced species richness. Yet, despite its increasingly recognized importance, how urbanization impacts on the health of individual animals, wildlife populations and on disease ecology remains poorly understood. To test whether, and how, urbanization-driven ecosystem alterations influence pathogen dynamics and avian health, we use house sparrows (Passer domesticus) and Yersinia spp. (pathogenic for passerines) as a case study. Sparrows are granivorous urban exploiters, whose western European populations have declined over the past decades, especially in highly urbanized areas. We sampled 329 house sparrows originating from 36 populations along an urbanization gradient across Flanders (Belgium), and used isolation combined with 'matrix-assisted laser desorption ionization- time of flight mass spectrometry' (MALDI-TOF MS) and PCR methods for detecting the presence of different Yersinia species. Yersinia spp. were recovered from 57.43% of the sampled house sparrows, of which 4.06%, 53.30% and 69.54% were identified as Y. pseudotuberculosis, Y. enterocolitica and other Yersinia species, respectively. Presence of Yersinia was related to the degree of urbanization, average daily temperatures and the community of granivorous birds present at sparrow capture locations. Body condition of suburban house sparrows was found to be higher compared to urban and rural house sparrows, but no relationships between sparrows' body condition and presence of Yersinia spp. were found. We conclude that two determinants of pathogen infection dynamics, body condition and pathogen occurrence, vary along an urbanization gradient, potentially mediating the impact of urbanization on avian health.

Yersinia pseudotuberculosis bloodstream infection and septic arthritis: case report and review of the literature

Yersinia pseudotuberculosis belongs to the family Enterobacteriaceae and is known to cause enterocolitis, terminal ileitis, pseudoappendicitis, erythema nodosum, reactive polyarthritis, and, occasionally, bloodstream infections. Here, we report the first case of bacteremia and septic arthritis in a patient without obvious risk factors and review all of the published cases of Y. pseudotuberculosis bloodstream infections.

Report of four cases of Yersinia pseudotuberculosis septicemia and a literature review

Yersinia pseudotuberculosis is a rare cause of disease in humans, the most common manifestation being mesenteric lymphadenitis accompanied by abdominal pain and fever. A septicemic form of Yersinia pseudotuberculosis infection has been reported only rarely. It is usually seen in patients with underlying disorders such as diabetes, hepatic cirrhosis or iron overload. Fifty-four cases of septicemic infection were found in the literature. The earlier published cases are reviewed, and four cases occurring in Finland during the period February to June 1992 are reported.

Haemochromatosis and aldosterone deficiency presenting with Yersinia pseudotuberculosis septicaemia

A 50 year old man presented with a pyrexial illness following a holiday abroad. Yersinia pseudotuberculosis was isolated from blood culture. Response to appropriate antibiotic therapy was prompt and complete, but full recovery was complicated by an episode of hyperkalaemia, hyponatraemia and the passing of large volumes of dilute urine. Three years previously he had developed diabetes mellitus and hypogonadotrophic hypogonadism. Investigation on recovery showed underlying haemochromatosis and aldosterone deficiency.

Yersinia pseudotuberculosis sepsis presenting as multiple liver abscesses

A 50-year-old man with diabetes was found to have sepsis with multiple small hepatic abscesses secondary to Yersinia pseudotuberculosis which were detected by computed tomography (CT) scan. Sepsis with Y. pseudotuberculosis is uncommon but usually seen in patients with underlying liver disease. Those patients with liver abscesses invariably have multiple small abscesses. Widespread use of CT scanning is likely to uncover more cases of hepatic microabscesses; in the appropriate clinical setting, Y. pseudotuberculosis should be considered as a possible cause.

Inhibition of bacterial multiplication by the iron chelator deferoxamine: potentiating effect of ascorbic acid

Since iron is essential for the multiplication of microorganisms, the effect of the iron chelator deferoxamine, with or without ascorbic acid, on the growth of 43 strains of Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Alcaligenes faecalis, Neisseria meningitidis and species of Salmonella, Enterobacter, Pseudomonas and Providencia, was investigated with the use of an automated turbidimeter. Addition of deferoxamine (25-400 micrograms/ml) to the incubation medium was inhibitory in a dose-dependent fashion. At concentrations between 200-400 micrograms/ml, growth was about 25% lower than control values. However, when ascorbic acid (100 micrograms/ml) was added to the culture medium, this antimicrobial activity of deferoxamine was significantly increased to on average 75% of the control value (p less than 0.05). Ascorbic acid alone had no bacteriostatic properties. Growth in the presence of 200 micrograms/ml deferoxamine combined with 100 micrograms/ml ascorbic acid was significantly lower than that in control media without additions (p less than 0.001). Addition of ferric citrate to the culture medium at a concentration sufficient to saturate all of the deferoxamine with iron, abolished the growth inhibiting effect of deferoxamine. The results provide evidence that deferoxamine is bacteriostatic due to its capacity to deplete iron which would otherwise be used for bacterial multiplication, and that ascorbic acid enhances this antibacterial property of deferoxamine.

[Critical study of serodiagnosis of Yersinia infections]

The study concerns 100 patients who are divided in two dissimilar groups. The first group is composed of 39 patients who have signs of possible Yersiniosis infection. In second group composed of 61 cirrhotics patients, the serodiagnosis was systematic. The rate of positive serology, comparing with healthy patients, is significantly high in both groups: 61,5 p. 100 (first group) 64 p. 100 (second group). Six cases in the first group were very likely caused by Yersinia infection and confirm the utility of the serodiagnosis in front of evocative symptomatology. But many positive serodiagnosis remain unexplained and the greatest care must be taken in appreciation of these results. Among cirrhotic patients, the positive serology is not correlated with evocative symptoms and would be the result of asymptomatic bacteriemias.

Yersinia pseudotuberculosis as the cause of septicaemia in a patient with amyloidosis

Septicaemia caused by Y. pseudotuberculosis in a female patient, aged 61, is reported. The patient suffered from amyloidosis with extensive infiltration of liver, spleen, and kidneys. While under treatment with corticosteroids and azathioprin, Y. pseudotuberculasis, serotype IA, was isolated from each of 6 blood cultures. The infection responded favourably to treatment with ampicillin. The development of Y. pseudotuberculosis septicaemia owing to impairment of the defence mechanisms by the underlying disease and the treatment given is discussed.

Terminal ileitis, mesenteric lymphadenitis and appendicitis due to Yersinia pseudotuberculosis type VA: case report

A case of terminal ileitis, mesenteric lymphadenitis and appendicitis is reported. Serological studies indicated infection with Yersinia pseudotuberculosis type VA. The patient's illness ran a chronic course necessitating resection of the terminal ileum. Histological examination of the appendix and a mesenteric lymph node in the acute stage revealed granulomas with central necrosis. This is the first human case in which the subtype VA has been identified.