Acute schistosomiasis: a risk underestimated by travelers and a diagnosis frequently missed by general practitioners-a cluster analysis of 42 travelers.

BACKGROUND: In 2011, a patient was admitted to our hospital with acute schistosomiasis after having returned from Madagascar and having bathed at the Lily waterfalls. On the basis of this patient's indication, infection was suspected in 41 other subjects. This study investigated (1) the knowledge of the travelers about the risks of schistosomiasis and their related behavior to evaluate the appropriateness of prevention messages and (2) the diagnostic workup of symptomatic travelers by general practitioners to evaluate medical care of travelers with a history of freshwater exposure in tropical areas. METHODS: A questionnaire was sent to the 42 travelers with potential exposure to schistosomiasis. It focused on pre-travel knowledge of the disease, bathing conditions, clinical presentation, first suspected diagnosis, and treatment. RESULTS: Of the 42 questionnaires, 40 (95%) were returned, among which 37 travelers (92%) reported an exposure to freshwater, and 18 (45%) were aware of the risk of schistosomiasis. Among these latter subjects, 16 (89%) still reported an exposure to freshwater. Serology was positive in 28 (78%) of 36 exposed subjects at least 3 months after exposure. Of the 28 infected travelers, 23 (82%) exhibited symptoms and 16 (70%) consulted their general practitioner before the information about the outbreak had spread, but none of these patients had a serology for schistosomiasis done during the first consultation. CONCLUSIONS: The usual prevention message of avoiding freshwater contact when traveling in tropical regions had no impact on the behavior of these travelers, who still went swimming at the Lily waterfalls. This prevention message should, therefore, be either modified or abandoned. The clinical presentation of acute schistosomiasis is often misleading. General practitioners should at least request an eosinophil count, when confronted with a returning traveler with fever. If eosinophilia is detected, it should prompt the search for a parasitic disease.

Acute Lyme Neuroborreliosis With Transient Hemiparesis and Aphasia.

Nervous system involvement in Lyme disease often mimics other conditions and thus represents a diagnostic challenge, especially in an emergency department setting. We report a case of a female teenager presenting with sudden-onset aphasia and transient right-sided faciobrachial hemiplegia, along with headache and agitation. Ischemia, vasculitis, or another structural lesion was excluded by brain imaging. Toxicologic evaluation results were negative. Cerebral perfusion computed tomography and electroencephalography showed left parietotemporal brain dysfunction. Lumbar puncture result, although atypical, suggested bacterial infection and intravenous ceftriaxone was initiated. Finally, microbiological cerebrospinal fluid analysis revealed Lyme neuroborreliosis, showing specific intrathecal antibody production and high level of C-X-C motif chemokine 13. The patient rapidly recovered. To our knowledge, this report for the first time illustrates that acute-onset language and motor symptoms may be directly related to Lyme neuroborreliosis. Neuroborreliosis may mimic other acute neurologic events such as stroke and should be taken into diagnostic consideration even in the absence of classic symptoms and evolution.

Schistosomiase aiguë au retour de voyage. Enseignements tirés d'une cohorte de 42 voyageurs exposés [Acute schistosomiasis: lessons learned from a cohort of 42 exposed travelers].

La schistosomiase aiguë est une pathologie régulièrement rencontrée chez les voyageurs. En raison de sa longue période d'incubation, de ses manifestations aspécifiques et de la résolution spontanée des symptômes, elle peut facilement ne pas être reconnue par un médecin peu familier des pathologies tropicales. En décembre 2011, une femme de retour de Madagascar, où elle avait été en contact avec de l'eau douce, a été hospitalisée pour un état fébrile d'origine indéterminé. Une schistosomiase aiguë a été diagnostiquée. Un dépistage chez tous les voyageurs de son groupe a révélé une séroconversion chez 78% des participants.Cet article cherche à rediscuter les mesures préventives et diagnostiques à la lumière des enseignements tirés de l'étude de cette cohorte de 42 voyageurs exposés à la schistosomiase. Acute schistosomiasis is a regularly encountered disease in travelers. Because of the temporal delay, its unspecific presentation and the spontaneous resolution, acute schistosomiasis can easily remain unrecognized by physicians who are not familiar with tropical pathologies. In December 2011, a female traveler was admitted to the hospital with undetermined fever after having returned from Madagascar where she bathed in fresh water. Acute schistosomiasis was diagnosed and infection was suspected among other travelers of her group. Seroconversion was confirmed among 78% of participants. This article intends to clarify the preventive and diagnostic strategies based on the lessons learned from this cluster of 42 travelers exposed to schistosomiasis.

The Impact of Infection on Chronic Allograft Dysfunction and Allograft Survival After Solid Organ Transplantation.

Infectious diseases after solid organ transplantation (SOT) are a significant cause of morbidity and reduced allograft and patient survival; however, the influence of infection on the development of chronic allograft dysfunction has not been completely delineated. Some viral infections appear to affect allograft function by both inducing direct tissue damage and immunologically related injury, including acute rejection. In particular, this has been observed for cytomegalovirus (CMV) infection in all SOT recipients and for BK virus infection in kidney transplant recipients, for community-acquired respiratory viruses in lung transplant recipients, and for hepatitis C virus in liver transplant recipients. The impact of bacterial and fungal infections is less clear, but bacterial urinary tract infections and respiratory tract colonization by Pseudomonas aeruginosa and Aspergillus spp appear to be correlated with higher rates of chronic allograft dysfunction in kidney and lung transplant recipients, respectively. Evidence supports the beneficial effects of the use of antiviral prophylaxis for CMV in improving allograft function and survival in SOT recipients. Nevertheless, there is still a need for prospective interventional trials assessing the potential effects of preventive and therapeutic strategies against bacterial and fungal infection for reducing or delaying the development of chronic allograft dysfunction.

Mycoplasma hominis mediastinitis after acute aortic dissection repair.

We report a case of ascending aortic graft infection by an atypical bacteria, Mycoplasma hominis, with mediastinitis, a dreaded complication after cardiac surgery. A 55-year-old patient underwent ascending aorta replacement for acute type A dissection. He developed sternal instability and purulent discharge, requiring sternal wire removal and debridement. Cultures were initially sterile, but showed M. hominis infection after a significant delay and in specific culture media. The patient was treated with doxycycline and moxifloxacine. Cultures became negative and the sternum was closed on the 28th postoperative day after the first debridement. Recovery was favorable, with no signs of infection. Antibiotics were continued for one year. The patient is still asymptomatic 16 months after antibiotic interruption. Atypical organisms should be considered in the differential diagnosis of acute mediastinitis of unknown etiology after routine microbiological investigations.

Treatment of Acute Otitis Media

Background: Acute otitis media (AOM) is the most common bacterial infection in young children, but the optimal management of AOM remains controversial. The aim of this study was to assess the efficacy of antimicrobial treatment, either immediate or delayed, for AOM and to compare parental experiences regarding the management of AOM in two countries with very different treatment guidelines. Methods: Altogether, 322 children participated in a randomized, double-blind, placebocontrolled trial. Children 6–35 months of age with AOM received amoxicillin-clavulanate or placebo for 7 days. The primary outcome was the time to treatment failure. In the second study, the delayed antimicrobial treatment group consisted of recipients of placebo who had received rescue treatment. The immediate antimicrobial treatment group consisted of children allocated to amoxicillin-clavulanate group. Parental expectations and opinions were evaluated by questionnaires sent via public day care in Turku, Finland, and Utrecht, the Netherlands. Results: Treatment failure occurred significantly more often in children receiving placebo as compared to antimicrobial treatment (45% vs. 19%, P<0.001). Delayed initiation of antimicrobial treatment did not worsen the recovery from AOM, but it was associated with worsening of the child’s condition, prolongation of symptoms, and absenteeism from day care and parental absenteeism from work. According to the comparative questionnaire, antimicrobial use was more common in Finland than in the Netherlands. Finnish parents believed more often than Dutch parents that antimicrobials are necessary in the treatment of AOM. Conclusions: Children with AOM benefit from antimicrobial treatment. Delayed initiation of antimicrobial does not worsen the overall recovery from AOM, but it might increase the symptom burden and create economic losses. Treatment practices and parental expectations seem to interact with each other. This needs to be considered when AOM treatment guidelines are updated.

Serum protein concentrations, including acute phase proteins, in calves experimentally infected with Salmonella Dublin

The aim of this study was to evaluate serum protein concentrations in calves experimentally inoculated with Salmonella Dublin. Twelve healthy 10 to 15-day-old Holstein calves were randomly allotted into two groups, control and infected with 10(8) CFU of Salmonella Dublin orally. The calves were subjected to physical evaluation and blood samples were collected shortly before administration of the bacteria and also 24, 48, 72, 96, 120 and 168 hours post-infection. The concentration of serum proteins was determined through sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Thirty serum proteins ranging from molecular weight of 24,000 Da to molecular weight of 236,000 Da were detected. Serum concentrations of ceruloplasmin (125,000 Da), haptoglobin (45,000 Da), acid glycoprotein (40,000 Da) and a 34,000 Da protein were significantly increased in the experimentally infected calves, when compared with their concentrations in the control animals. Therefore, this study showed that S. Dublin infection could lead to the increase of certain serum proteins in calves.

Effects of intramammary infection on whey proteinograms of sheep during lactation

The study aimed to identify potential biomarkers of mammary gland infection in Santa Inês sheep. Commercial flocks of sheep provided the same hygiene, sanitary, and nutritional management under semi-intensive production systems were monitored during the lactation stage-and assessed 15, 30, 60, and 90 days after delivery (through the end of lactation and weaning). The California Mastitis Test (CMT) was performed on the mammary glands. Milk was collected for bacterial examination and protein analysis. Bacterial culture and biochemical characterization of the samples were performed. Forty-two milk samples from healthy glands (negative CMT and bacterial testing) and 43 milk samples from infected glands (positive CMT and bacterial testing) taken at the predefined time points were assessed. A rennin solution was used to obtain the whey. The proteins analysis was performed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), which allowed for the quantification of nine whey proteins produced in healthy glands: serum albumin, lactoferrin, IgA, IgG heavy-chain (IgG HC), IgG light-chain (IgG LC), total IgG (IgG HC + IgG LC), α-lactalbumin, β-lactoglobulin, protein with MW 15.000 Da, protein with MW 29.000 Da and eleven whey proteins secreted by infected glands, including haptoglobin and α-1-acid glycoprotein. A comparison of whey proteins between healthy and infected glands showed increases (P<0.05) in the secreted and total contents of all proteins, except for IgG LC and α-lactoalbumin. The most significant changes were observed in α-1-acid glycoprotein, lactoferrin and haptoglobin, which showed three-, five-, and seven-fold increases in secretion, respectively. This study showed that haptoglobin, α-1-acid glycoprotein, lactoferrin, albumin, and the IgA and IgG immunoglobulins may serve as potential biomarkers for mammary gland infection in sheep.

Oestrus ovis infection of grazing sheep during summer in southern Chile

Abstract: Oestrus ovis is a botfly whose larvae cause nasal myiasis, an environmental-dependent disease in small ruminants, generating acute and chronic injuries in the cranial cavities of sheep. Chile is a country of the southernmost worldwide distribution of this parasite, and there is few information about. Whence, the objective of this study was to approximate the epidemiological situation of O. ovis infection in Chilean sheep. From December 2009 to March 2010, a total of 87 samples were obtained by necropsy for skull inspection. The larvae were collected, and microscopically identified. The prevalence in the sampled sheep was 60.9%. From those that were infected, 85.7% (18/21) of sheep were 1 to 3 years old, constituting the stratum with the highest prevalence. The difference of infection in females and males was not significant. The high risk of infection seems to be dependent upon the environmental conditions of this southern region, especially during summer when the first larval stage (L1) could be found as the evidence. Therefore, the disease should be considered as a significant problem for this kind of livestock production.

Rabies infection and specific effect of vaccination in mice selected for high and low immunobiological parameters

Innate and acquired resistance to rabies infection was investigated in mice genetically selected for high (H) or low (L) antibody responsiveness from selections I, III and IV and in mice selected for maximal (AIRmax) or minimal (AIRmin) acute inflammatory reaction. These mouse lines were infected intramuscularly with different virus dilutions and the LD50 was determined. The HIII and HIV mouse lines were more susceptible than the LIII and LIV lines and the HI line showed a discrete but higher resistance than the LI line. Analysis of the interline (H x L) F1 hybrids from selections III and IV indicated different dominance effects on the "resistant" and" susceptible" phenotypes when the route of vaccination was changed. No differences were observed between the AIRmax and AIRmin mice, suggesting that inflammation plays a minor role in the resistance to rabies virus. The comparison of LD50 in mice vaccinated by distinct routes showed that the highest interline difference occurred after intramuscular vaccination (250-fold between H and L and 800-fold between F1 and L). These results indicate that different mechanisms may participate in acquired antirabies resistance

Induction of cell-mediated immunity during early stages of infection with intracellular protozoa

Toxoplasma gondii and Trypanosoma cruzi are intracellular parasites which, as part of their life cycle, induce a potent cell-mediated immunity (CMI) maintained by Th1 lymphocytes and IFN-g. In both cases, induction of a strong CMI is thought to protect the host against rapid parasite multiplication and consequent pathology and lethality during the acute phase of infection. However, the parasitic infection is not eliminated by the immune system and the vertebrate host serves as a parasite reservoir. In contrast, Leishmania sp, which is a slow growing parasite, appears to evade induction of CMI during early stages of infection as a strategy for surviving in a hostile environment (i.e., inside the macrophages which are their obligatory niche in the vertebrate host). Recent reports show that the initiation of IL-12 synthesis by macrophages during these parasitic infections is a key event in regulating CMI and disease outcome. The studies reviewed here indicate that activation/inhibition of distinct signaling pathways and certain macrophage functions by intracellular protozoa are important events in inducing/modulating the immune response of their vertebrate hosts, allowing parasite and host survival and therefore maintaining parasite life cycles.

The role of IL-12 in experimental Trypanosoma cruzi infection

Host resistance to Trypanosoma cruzi infection is dependent on both natural and acquired immune responses. During the early acute phase of infection in mice, natural killer (NK) cell-derived IFN-g is involved in controlling intracellular parasite replication, mainly through the induction of nitric oxide biosynthesis by activated macrophages. We have shown that IL-12, a powerful inducer of IFN-g production by NK cells, is synthesized soon after trypomastigote-macrophage interaction. The role of IL-12 in the control of T. cruzi infection in vivo was determined by treating infected mice with anti-IL-12 monoclonal antibody (mAb) and analyzing both parasitemia and mortality during the acute phase of infection. The anti-IL-12 mAb-treated mice had higher levels of parasitemia and mortality compared to control mice. Also, treatment of infected mice with mAb specific for IFN-g or TNF-a inhibited the protective effect of exogenous IL-12. On the other hand, TGF-ß and IL-10 produced by infected macrophages inhibited the induction and effects of IL-12. Therefore, while IL-12, TNF-a and IFN-g correlate with resistance to T. cruzi infection, TGF-ß and IL-10 promote susceptibility. These results provide support for a role of innate immunity in the control of T. cruzi infection. In addition to its protective role, IL-12 may also be involved in the modulation of T. cruzi-induced myocarditis, since treatment of infected mice with IL-12 or anti-IL-12 mAb leads to an enhanced or decreased inflammatory infiltrate in the heart, respectively. Understanding the role of the cytokines produced during the acute phase of T. cruzi infection and their involvement in protection and pathogenesis would be essential to devise new vaccines or therapies.

Cytokines as determinants of resistance and pathology in human Schistosoma mansoni infection

The role of different cytokines in the peripheral blood mononuclear cell (PBMC) proliferative response and in in vitro granuloma formation was evaluated in a cross-sectional study with patients with the different clinical forms and phases of Schistosoma mansoni infection, as well as a group of individuals "naturally" resistant to infection named normal endemic (NE). The blockage of IL-4 and IL-5 using anti-IL-4 and anti-IL-5 antibodies significantly reduced the PBMC proliferative response to soluble egg (SEA) and adult worm (SWAP) antigens in acute (ACT), chronic intestinal (INT) and hepatosplenic (HS) patients. Similar results were obtained in the in vitro granuloma formation. Blockage of IL-10 had no significant effect on either assay using PBMC from ACT or HS. In contrast, the addition of anti-IL-10 antibodies to PBMC cultures from INT patients significantly increased the proliferative response to SEA and SWAP as well as the in vitro granuloma formation. Interestingly, association of anti-IL-4 and anti-IL-10 antibodies did not increase the PBMC proliferative response of these patients, suggesting that IL-10 may act by modulating IL-4 and IL-5 secretion. Addition of recombinant IL-10 decreased the proliferative response to undetectable levels when PBMC from patients with the different clinical forms were used. Analysis of IFN-g in the supernatants showed that PBMC from INT patients secreted low levels of IFN-g upon antigenic stimulation. In contrast, PBMC from NE secreted high levels of IFN-g. These data suggest that IL-10 is an important cytokine in regulating the immune response and possibly controlling morbidity in human schistosomiasis mansoni, and that the production of IFN-g may be associated with resistance to infection.

Expression of extracellular matrix components and their receptors in the central nervous system during experimental Toxoplasma gondii and Trypanosoma cruzi infection

Alterations in extracellular matrix (ECM) expression in the central nervous system (CNS) usually associated with inflammatory lesions have been described in several pathological situations including neuroblastoma and demyelinating diseases. The participation of fibronectin (FN) and its receptor, the VLA-4 molecule, in the migration of inflammatory cells into the CNS has been proposed. In Trypanosoma cruzi infection encephalitis occurs during the acute phase, whereas in Toxoplasma infection encephalitis is a chronic persisting process. In immunocompromised individuals such as AIDS patients, T. cruzi or T. gondii infection can lead to severe CNS damage. At the moment, there are no data available regarding the molecules involved in the entrance of inflammatory cells into the CNS during parasitic encephalitis. Herein, we characterized the expression of the ECM components FN and laminin (LN) and their receptors in the CNS of T. gondii- and T. cruzi-infected mice. An increased expression of FN and LN was detected in the meninges, leptomeninges, choroid plexus and basal lamina of blood vessels. A fine FN network was observed involving T. gondii-free and T. gondii-containing inflammatory infiltrates. Moreover, perivascular spaces presenting a FN-containing filamentous network filled with a4+ and a5+ cells were observed. Although an increased expression of LN was detected in the basal lamina of blood vessels, the CNS inflammatory cells were a6-negative. Taken together, our results suggest that FN and its receptors VLA-4 and VLA-5 might be involved in the entrance, migration and retention of inflammatory cells into the CNS during parasitic infections.

HEV, TTV and GBV-C/HGV markers in patients with acute viral hepatitis

The aim of the present study was to evaluate the prevalence of HEV, TTV and GBV-C/GBV-C/HGV in patients with acute viral hepatitis A, B and non-A-C. We evaluated sera of 94 patients from a sentinel program who had acute hepatitis A (N = 40), B (N = 42) and non-A-C (N = 12); 71 blood donors served as controls. IgM and anti-HEV IgG antibodies were detected by enzyme immunoassay using commercial kits. TTV and GBV-C/HGV were detected by nested PCR; genotyping was done by sequencing and phylogenetic analysis. Anti-HEV IgG was present in 38, 10 and 17% of patients with hepatitis A, B and non-A-C. Four patients with hepatitis A and 1 with non-A-C hepatitis also had anti-HEV IgM detected in serum. TTV was detected in 21% of patients with acute hepatitis and in 31% of donors. GBV-C/HGV was detected in 9% of patients with hepatitis, and in 10% of donors. We found TTV isolates of genotypes 1, 2, 3, and 4 and GBV-C/HGV isolates of genotypes 1 and 2. Mean aminotransferase levels were lower in patients who were TTV or GBV-C/HGV positive. In conclusion, the detection of anti-HEV IgM in some acute hepatitis A cases suggests co-infection with HEV and hepatitis E could be the etiology of a few cases of sporadic non-A-C hepatitis in Salvador, Brazil. TTV genotype 1, 2, 3 and 4 isolates and GBV-C/HGV genotype 1 and 2 strains are frequent in the studied population. TTV and GBV-C/HGV infection does not appear to have a role in the etiology of acute hepatitis.