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A case of bilateral psoas abscesses and lumbar osteomyelitis due to recurrent salmonella infection.

Psoas abscess and lumbar osteomyelitis due to salmonella infection is very rare, although it is frequently seen all over the world. These two complications have severe clinical progress, poor prognosis and high mortality. Here, we report a case of salmonellosis presenting with bilateral multiple psoas abscesses and lumbar osteomyelitis, which resolved completely following medical treatment and percutoneous drainage of abscess.

Anti-Infective Agents↗

Polyarthritis associated with Salmonella infection in rats.

Rats infected intravenously with Salmonella enteritidis develop a chronic destructive polyarthritis. The joint lesions resemble those of human rheumatoid arthritis in distribution and pathology. On the basis of histological and microbiological studies, involvement does not appear to be the result of intra-articular sepsis. Instead, the data favor the view that transient infection incites an immunological response that localizes in the joint and becomes destructive.

Animals↗

The innate immune response differs in primary and secondary Salmonella infection.

This study examines innate immunity to oral Salmonella during primary infection and after secondary challenge of immune mice. Splenic NK and NKT cells plummeted early after primary infection, while neutrophils and macrophages (Mphi) increased 10- and 3-fold, respectively. In contrast, immune animals had only a modest reduction in NK cells, no loss of NKT cells, and a slight increase in phagocytes following secondary challenge. During primary infection, the dominant sources of IFN-gamma were, unexpectedly, neutrophils and Mphi, the former having intracellular stores of IFN-gamma that were released during infection. IFN-gamma-producing phagocytes greatly outnumbered IFN-gamma-producing NK cells, NKT cells, and T cells during the primary response. TNF-alpha production was also dominated by neutrophils and Mphi, which vastly outnumbered NKT cells producing this cytokine. Neither T cells nor NK cells produced TNF-alpha early during primary infection. The TNF-alpha response was reduced in a secondary response, but remained dominated by neutrophils and Mphi. Moreover, no significant IFN-gamma production by Mphi was associated with the secondary response. Indeed, only NK1.1(+) cells and T cells produced IFN-gamma in these mice. These studies provide a coherent view of innate immunity to oral Salmonella infection, reveal novel sources of IFN-gamma, and demonstrate that immune status influences the nature of the innate response.

Animals↗

The cytokinetics of monocytosis in acute salmonella infection in the rat.

The mechanisms responsible for monocytosis occurring in acute Salmonella infection were studied by means of isotopic labeling and autoradiography. Male (Lewis x BN)F(1) hybrid rats (160-180 g) were pulse-labeled with [(3)H]TdR at varying intervals with respect to the time of i.v. injection of about 10(6) living Salmonella enteritidis. The half time for monocytes in the blood was estimated from the exponential decline in the percentage of labeled monocytes. The average generation time for dividing monocyte precursors in bone marrow was estimated by fitting a regression line to the decline in median grain counts (halving-time = T(G)). After an initial fall, the absolute number of blood monocytes rose to a plateau about 2.5 x normal on day 5, suggesting the reimposition of steady state conditions. The half time of monocytes in the blood of infected rats was shortened to 25 h throughout the infection, compared with 61 h estimated in uninfected rats. T(G) was reduced to 15 h (days 1-3) but later reverted to the preinfection level of 34 h (days 4-8). Another early response to infection was the release of immature monocytes into the blood. These cells, however, were too few to offset the initial monocytopenia. Under these conditions, with little or no division of blood monocytes, the sustained monocytosis (days 4-8) must have been due to enlargement of the dividing precursor pool. Excessive loss of monocytes from the blood thus appears to activate a feedback mechanism. However, a more direct stimulating effect on monocyte production by endotoxin could have contributed substantially to the monocytosis.

Animals↗

Effect of late administration of anti-TNF alpha antibodies on a Salmonella infection in the mouse model.

The effect of late administration of anti-TNF alpha antibodies on the course of a Salmonella infection in mice was evaluated. Administration of anti-TNF alpha antiserum as late as day 5 after challenge enhanced a sublethal primary infection with the virulent Salmonella typhimurium C5 in innately resistant (Ityr) A/J mice by preventing the suppression of exponential bacterial growth in the reticuloendothelial system (RES) (plateau phase). When the anti-TNF alpha treatment was started well after the establishment of the plateau (day 7) a prompt relapse of the infection occurred, with the rapid resurgence of bacterial growth in the reticuloendothelial system leading to the death of the animals. In contrast, late administration of the antiserum did not affect the clearance from the tissues of an avirulent temperature-sensitive mutant of S. typhimurium C5 (C5TS). Innately susceptible (Itys) BALB/c mice immunized with the SL3261 aroA live vaccine acquire solid long-lasting protection from oral challenge with the virulent C5 strain, suppressing growth of the challenge in the RES. Administration of anti-TNF alpha antibodies on day 8 of a secondary oral infection with strain C5 abrogated vaccine-induced protection, with a progressive increase of bacterial numbers in the RES leading to the death of the animals. The results indicate that TNF alpha is constantly required for the control of virulent salmonellae in the RES, both in a sublethal primary infection in innately resistant mice and also in a secondary infection in innately susceptible mice immunized with a live vaccine. TNF alpha may not be essential for bacterial clearance of avirulent organisms from the tissues.

Animals↗

Wound dehiscence after cholecystectomy and salmonella infection.

A case of a wound dehiscence following a Salmonella wound infection is reported. Cholecystectomy for the typhoid carrier state is not an uncommon operation and carries the risk of Salmonella wound infection in about 7 per cent of the cases. Wound dehiscence with this type of infection has not previously been reported.

Cholecystectomy↗

Ruptured mycotic aneurysm of a coronary artery. A fatal complication of Salmonella infection.

A 53-year-old man with a kidney transplant was hospitalized because of back pain, fever, and an enlarging heart size. Cultures of blood and stool yielded Salmonella enteritidis (group D, serotype enteritidis). Despite appropriate antibiotic therapy, the patient died of cardiac arrest on the seventh hospital day. Autopsy revealed a ruptured mycotic aneurysm of the right coronary artery with hemopericardium. In addition, a ruptured aneurysm of the abdominal aorta was present. To our knowledge, ruptured mycotic aneurysm involving a coronary artery owing to Salmonella infection has not been described previously.

Aneurysm, Infected↗

A population-based longitudinal study on the incidence and disease burden of gastroenteritis and Campylobacter and Salmonella infection in four regions of The Netherlands.

The aim of this study was to estimate the incidence of gastroenteritis and Campylobacter and Salmonella infection in the Dutch population, the disease burden, and the percentage of patients with gastroenteritis that consults a general practitioner. A sample of 6243 persons was invited to participate in the study, i.e. completing a questionnaire and submitting stool samples. The follow-up period was 17 weeks. In total, 2206 persons participated (= 35%), contributing 660 person years. The incidence (standardised by age and gender) of first episodes of gastroenteritis was 45 per 100 person years. Among patients with gastroenteritis, Salmonella and Campylobacter were cultured in 1.6 and 4.5%, respectively. The standardised incidence of first Campylobacter infections was 9 per 100 person years, of first Salmonella infections 4 per 100 person years. For 22% of the episodes of gastroenteritis, a general practitioner was consulted (either by phone or by practice visit). For 52% of the episodes, medicine were used. For 34% of the episodes, absence from school was reported and for 15%, absence from work was reported. Despite of possible biases, we can conclude that the incidence of gastroenteritis is very high and causes considerable use of medication, consultation of general practitioners and absence from work and school.

Adolescent↗

Seroreactivity of Salmonella-infected cattle herds against a fimbrial antigen in comparison with lipopolysaccharide antigens.

The IgG seroreaction of Salmonella-infected cattle herds against a fimbrial antigen (SEF14) was compared with that against lipopolysaccharide (LPS) antigens. Sera from 23 dairy herds (n = 205) from an island with no occurrence of salmonellosis, four herds (n = 303) with recent outbreaks of S. dublin and four herds (n = 168) with recent outbreaks of S. typhimurium, were tested in a SEF14-ELISA, S. dublin LPS (0:1, 9, 12) ELISA and S. typhimurium LPS (0:1, 4, 5, 12) ELISA. At a cut-off OD of 0.5, only one of the animals tested from the salmonellosis-free island showed significant seroreaction against the SEF14 antigen, which was confirmed in a Western-blot analysis. Three out of the four S. dublin-infected herds had several seroreactors in the SEF14-ELISA, whereas all the four herds were positive in the 0:1, 9, 12-ELISA. All but two samples (both from the same herd) in the four S. typhimurium-infected herds, positive in the 0:1, 4, 5, 12-ELISA, had OD values below 0.5 in the SEF14-ELISA. The results indicate that cattle can produce detectable specific antibodies against fimbrial antigens which may be used for screening of S. dublin-infected herds, particularly in areas with low prevalence of salmonellosis, increasing the predictive value of serology.

Animals↗

Salmonella infection of bone marrow-derived macrophages and dendritic cells: influence on antigen presentation and initiating an immune response.

Traditionally macrophages (MPhi) have been considered to be the key type of antigen presenting cells (APC) to combat bacterial infections by phagocytosing and destroying bacteria and presenting bacteria-derived antigens to T cells. However, data in recent years have demonstrated that dendritic cells (DC), at their immature stage of differentiation, are capable of phagocytosing particulate antigens including bacteria. Thus, DC may also be important APC for initiating an immune response to bacterial infections. Our studies focus on studying how DC and MPhi process antigens derived from bacteria with no known mechanism of phagosomal escape (i.e. Salmonella typhimurium) for T cell stimulation as well as what role these APC types have in Salmonella infection in vivo. Using an in vitro antigen processing and presentation assay with bone marrow-derived (BM) APC showed that, in addition to peritoneal elicited MPhi and BMMPhi, BMDC can phagocytose and process Escherichia coli and S. typhimurium for peptide presentation on major histocompatibility complex (MHC) class I (MHC-I) and class II MHC-II. These studies showed that both elicited peritoneal MPhi and BMMPhi use an alternate MHC-I presentation pathway that does not require the transporter associated with antigen processing (TAP) or the proteasome and involves peptide loading onto a preformed pool of post-Golgi MHC-I molecules. In contrast, DC process E. coli and S. typhimurium for peptide presentation on MHC-I using the cytosolic MHC-I presentation pathway that requires TAP, the proteasome and uses newly synthesized MHC-I molecules. We further investigated the interaction of Salmonella with BMDC and BMMPhi by analyzing surface molecule expression and cytokine secretion following S. typhimurium infection of BMDC and BMMPhi. These data reveal that Salmonella co-incubation with BMDC as well as BMMPhi results in upregulation of MHC-I and MHC-II as well as several co-stimulatory molecules including CD80 and CD86. Salmonella infection of BMDC or BMMPhi also results in secretion of cytokines including IL-6 and IL-12. Finally, injecting mice with BMDC that have been loaded in vitro with S. typhimurium primes naïve CD4(+) and CD8(+) T cells to Salmonella-encoded antigens. Taken together, our data suggest that DC may be an important type of APC that contributes to the immune response to Salmonella.

Animals↗

Breast-feeding and Salmonella infection.

Various assays were used to examine chemotaxis, opsonization, phagocytosis, and killing of Salmonella organisms by colostral and breast-milk components. Vigorous responses of colostral a;d milk cells against this organism and nonspecific opsonizing capacity of the aqueous phase of colostrum and milk were demonstrated. An assay with acridine orange was used to directly visualize the phagocytic and killing processes; colostral and milk cells were demonstrated to be more active against Salmonella than blood neutrophils. In a retrospective survey, a diagnosis of Salmonella infection was confirmed in 253 infants less then 1 year of age. Only 12 infants had ever been breast-fed, and only one near the time he had the disease. During the same period of time, 27% of matched control infants were breast-fed.

Breast Feeding↗

CD154 is essential for protective immunity in experimental salmonella infection: evidence for a dual role in innate and adaptive immune responses.

CD40-CD154 interactions are of central importance in the induction of humoral and cellular immune responses. In the present study, CD154-deficient (CD154-/-) mice were used to assess the role of CD40-CD154 interactions in regulating the immune response to a systemic Salmonella infection. Compared with C57BL/6 (CD154+/+) controls, CD154-/- mice were hypersusceptible to infection by an attenuated strain of Salmonella enterica serovar Typhimurium (S. typhimurium), as evidenced by decreased survival rate and mean time to death, which correlated with increased bacterial burden and persistence in target organs. CD154-/- mice exhibited a defect both in the production of IL-12, IFN-gamma, and NO during the acute phase of the disease and in the generation of Salmonella-specific Ab responses and Ig isotype switching. Furthermore, when CD154-/- animals were administered a sublethal dose of attenuated S. typhimurium and subsequently challenged with a virulent homologous strain, all mice succumbed to an overwhelming infection. Similar treatment of CD154+/+ mice consistently resulted in > or =90% protection. The lack of protective immunity in CD154-/- mice correlated with a decreased T cell recall response to Salmonella Ags. Significant protection against virulent challenge was conferred to presensitized CD154-/- mice by transfer of serum or T cells from immunized CD154+/+ mice. For best protection, however, a combination of immune serum and T cells was required. We conclude that intercellular communications via the CD40-CD154 pathway play a critical role in the induction of type 1 cytokine responses, memory T cell generation, Ab formation, and protection against primary as well as secondary Salmonella infections.

Adoptive Transfer↗