Reemergence of Strongyloidiasis, Northern Italy

Strongyloidiasis is a helminth infection caused by Strongyloides stercoralis, a nematode ubiquitous in tropical and subtropical countries and occasionally reported in temperate countries, including Italy (1). Sources of infection are filariform strongyloid larvae present in soil contaminated by infected feces; the larvae penetrate through the skin of a human host. After the first life cycle, a process of autoinfection begins, which persists indefinitely in the host if the infection is not effectively treated. The infection can remain totally asymptomatic for many years or forever or cause cutaneous (itching and rash), abdominal (epigastric pain, pseudoappendicitis, diarrhea), respiratory (cough, recurrent asthma), and systemic (weight loss, cachexia) symptoms that can be enervating. More importantly, when host immunity is impaired because of a concurrent disease or immunosuppressive therapy (including corticosteroids, sometimes used to treat symptoms of the unrecognized infection or the concurrent eosinophilia), disseminated strongyloidiasis may occur (2\u20134), causing a massive and almost invariably fatal invasion of virtually all organs and tissues by filariform larvae and even adult worms (Figure), often combined with bacterial superinfection. This complication is believed to be rare but is probably underestimated because of the extreme variability of the clinical presentation. Although strongyloidiasis can be suspected in the presence of symptoms or eosinophilia (which is frequent but not mandatory), the low sensitivity of direct diagnostic methods often lets the disease go unrecognized (5\u20137). By far the most sensitive diagnostic tools are serologic tests: sensitivity and specificity of indirect fluorescent antibody test (IFAT) (in-house produced IFAT) are 97.4% and 97.9%, respectively, at a dilution >1/20, and 70.5% and 99.8% at a dilution >1/80 (6). A suspected case is defined by a positive antibody titer >20 (IFAT); a case is confirmed by a positive direct test result (culture in agar being the most sensitive direct technique) or by a positive antibody titer >80 (6). Despite some anecdotal reports on the presence of strongyloidiasis in Italy (1,6), reliable information about the real prevalence of the infection is lacking. After seeing several patients affected by the disease, 1 of whom died because of dissemination (Z. Bisoffi, unpub. data), we decided to carry out a preliminary rapid assessment of the extent of the problem in elderly patients with eosinophilia. During a 4-month period, from February through May 2008, every patient born in 1940 or earlier who came to the clinical laboratories of 2 contiguous health districts in northern Italy (Mantova, Lombardy Region, and Legnago, Veneto Region) for a diagnostic blood test (hematocrit and leukocyte count/formula) for whatever reason and having a eosinophil count >500 cells/\u3bcL was asked to join the study. This study was the pilot phase of a larger, multicentered study, which obtained formal approval from the Ethical Committee of Sacro Cuore Hospital of Negrar, Verona. Informed consent was required of each patient. Of the 132 patients eligible for inclusion (mean age 76.4 years, range 68\u201390 years, male:female ratio 1.6), none refused to give informed consent. Serum specimens were subjected to the IFAT for S. stercoralis at the Sacro Cuore Hospital Centre for Tropical Diseases. Unexpectedly, we found that 37 (28%) of 132 patients were positive, with titers ranging between 20 and >320 (and >80 in most cases). However, caution should be exercised in interpreting the results because the patients may not be representative of the general population. Moreover, our results are based on an indirect (although highly sensitive and specific) test. Because the reported cases involve only a few patients every year (of whom some are anecdotally reported as dying from the infection, usually unpublished), we suspect that most strongyloidiasis cases remain undetected. If relevant transmission still exists in the area, it is unknown but is unlikely because of the improvement of hygienic conditions in the past 5 decades. Reports of the infection in children or young adults with no travel history outside Italy are lacking. Strongyloidiasis in the elderly is therefore most likely to result from an infection that occurred much earlier in life, either in infancy or at a young age, while walking or working barefoot in agricultural fields. The long persistence is the consequence of the autoinfection cycle typical of this parasite as described above. The result is an important and unrecognized public health problem affecting the geriatric population of northern Italy. These preliminary results confirm the need for the already planned, multicentered study involving a larger sample and a wider geographic area

The ocean sampling day consortium

Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world’s oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits

The Ocean Sampling Day Consortium

Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world’s oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits

Selenium dependent glutathione peroxidase: a physiological regulatory system for platelet function

In human platelets the selenoenzyme glutathione peroxidase (GSH-Px) acts as a scavenger of the peroxides generated during the burst of arachidonic acid (AA) metabolism. Such a mechanism inhibits the biosynthesis of both thromboxane A2 (TXA2) and lipoxygenase products. The same mechanism is not effective on the prostacyclin (PGI2) biosynthesis from cultured endothelial cells. In order to evaluate this effect in vivo, besides in vitro, we activated the enzyme in eight normal volunteers by increasing their daily Se intake for 8 weeks, monitoring: platelet GSH-Px activity, platelet aggregation induced by AA and U 44069, and concurrent malondialdehyde (MDA) and thromboxane B2 (TXB2) production, urinary excretion of renal and systemic TXA2 and PGI2 metabolites, platelet enzyme activities of the hexose monophosphate pathway and glutathione content, platelet adenine nucleotides, bleeding time, plasma Se concentration. We found: a) progressive platelet GSH-Px activation by Se paralleling an enhancement of platelet aggregation threshold values for AA, but not for U 44069; b) concurrent inhibition of platelet biosynthesis of TXA2 both in vitro and in vivo while the biosynthesis of systemic prostacyclin was unaffected; c) a progressive increase in the bleeding time, unmodified by aspirin. In conclusion, we believe that Se-dependent GSH-Px represents a physiological mechanism regulating the biosynthesis of prostanoids with implications in platelet function and that a Se dietary supplement might be considered in the prevention of arterial thrombosis

Novel serum paraoxonase activity assays are associated with coronary artery disease

BACKGROUND: Serum paraoxonase (PON1) exerts antiatherogenic effects. Novel PON1 enzymatic tests have been recently developed: 5-thiobutyl butyrolactone (TBBL) estimates PON1 lactonase activity, whereas 7-O-diethylphosphoryl-3-cyano-4-methyl-7-hydroxycoumarin (DEPCyMC) is considered a surrogate marker of PON1 concentration. The TBBL to DEPCyMC ratio provides the normalized lactonase activity (NLA), which may reflect the degree of PON1 lactonase catalytic stimulation. The aim of this study was to evaluate for the first time TBBLase and DEPCyMCase activity in patients with coronary artery disease (CAD). METHODS: An angiography-based case-control study was conducted, including 300 sex- and age-matched subjects [100 CAD-free, 100 CAD without myocardial infarction (MI) and 100 CAD with MI]. RESULTS: A low DEPCyMCase activity (lowest vs. highest tertile: OR 2.96, 95\% CI 1.18-7.43) and a high NLA (highest vs. lowest tertile: OR 3.25, 95\% CI 1.28-8.26) were both associated with CAD, independent of classical atherosclerosis risk factors, lipid-lowering therapy and PON1 genotype. Total TBBLase activity was, however, not different in CAD compared to CAD-free subjects. CONCLUSIONS: Novel PON1 activity assays may be associated with CAD. In this study, CAD patients had low DEPCyMCase activity, a possible marker of low PON1 concentration, but showed a high stimulation of PON1 lactonase activity