Prevalence of Enteric Pathogens and Antibiotic Resistance: Results of a Six-Year Active Surveillance Study on Patients Admitted to a Teaching Hospital.

BACKGROUND: Acute Infectious Diarrhea (AID) and the short- and long-term complications associated with it are major causes of hospitalization worldwide. In Italy, due to a lack of robust surveillance programs, only limited data has been collected on their prevalence and circulation. This study aims to evaluate the resistance pattern of enteric pathogens and their epidemiological trends over a six-year period. METHODS: This cross-sectional retrospective study was conducted from January 2018 to December 2023. Stool samples were analyzed during routine diagnosis with culture methods, syndromic molecular tests, and enzyme immunoassay. RESULTS: Bacteria were the most isolated enteric pathogens (62.2%), followed by fungi (29.0%), viruses (8.2%), and parasites (0.6%). Most bacteria were isolated from outpatients (29.5%) and from patients in the Oncology ward (26.2%). The most prevalent target was EPEC (11.1%), followed by C. difficile toxin A/B-producing strains (8.3%), C. jejuni (2.5%), and S. enterica, (1%.). Norovirus and Candida spp. were the most prevalent in pediatric patients (6.5% and 39.6%, respectively). In the last years, enteric pathogens have been a frequent cause of infections characterized by a problematic resistance to common antimicrobials. In our study, S. enterica showed resistance to amikacin, gentamicin, ampicillin, levofloxacin, and ciprofloxacin. C. jejuni was susceptible to all tested drugs. CONCLUSION: Timely notification of gastroenteric infections is crucial in identifying potential outbreak sources and ensuring strict adherence to food safety and hygiene practices, so as to protect the most vulnerable populations. The present study offers insights into the epidemiological characteristics and the antibiotic susceptibility of the main enteric AID pathogens in order to implement infection control measures in health care settings.

An autochthonous case of cutaneous bacillary angiomatosis not related to major immunosuppression: An emerging or overlooked disease?

Cutaneous bacillary angiomatosis (cBA) is a vascular proliferative disorder due to Bartonella henselae or Bartonella quintana that has been mostly described in people living with HIV. Since cBA is considered to be rare in hosts not affected by major immunosuppression, it could be underdiagnosed in this population. Moreover, antimicrobial treatment of cBA has been poorly validated, thus reporting experiences on this clinical entity is important. We reported a challenging and well-characterized case of an Italian 67-year-old gentleman without a history of major immunocompromizing conditions, although he was affected by conditions that can be associated with impaired immune function. The patient reported herein was diagnosed after a long time since the initiation of symptoms and was successfully treated with combined antibiotic therapy including macrolides and quinolones under the guidance of molecular test results. Physicians should consider cBA as a possible manifestation of Bartonella spp. Infection in patients not suffering from major immunocompromizing conditions. Until evidence-based guidelines are available, molecular tests together with severity and extension of the disease can be useful to personalize the type of treatment and its duration.

Prevalence of parasitic infections in migrants: do official symptom-driven guidelines apply to the current situation?

In recent years, migration has become a significant challenge in Western countries. Migrant populations, coming from hyper-endemic areas, may present parasitic infections that remain latent and asymptomatic even for years, eventually leading to severe complications. Italian guidelines have been established to perform screening guided by the presence of symptoms and/or hypereosinophilia. Parasitological screening was conducted in a migrant population to carry out preventative measures. All migrants were asked to report any symptoms suggesting parasitic infections and list any previous treatment received. Travel data were recorded. Parasitological examination of stools and urine were conducted in all patients regardless of symptoms. In all, 208 consecutive patients were enrolled in our outpatient clinic from November 2016 to August 2017. Thirty-four patients were excluded due to the previous assumption of albendazole or because they did not exhibit suitable samples. Prevalence of parasitic infections was 33/174 (18.9%). A statistically significant difference for the prevalence of parasitic infections was not found between patients who were asymptomatic and without hypereosinophilia compared to those who presented symptoms and/or hypereosinophilia (27/151 [17.9%] vs. 6/23 [26.0%]; p=0.39). By contrast, a statistically significant difference was found for the length of time between arrival in Italy and parasitological examinations (4/51 [7.8%] migrants who arrived in Italy more than six months prior to screening vs. 29/123 [23.6%] migrants who arrived within six months; p= 0.016). Our results did not demonstrate any significant differences in prevalence of parasitic infections between symptomatic or hypereosinophilic and asymptomatic migrants. Thus we feel it inappropriate to support recent guidelines recommending parasitological examinations only in migrants with symptoms and/or hypereosinophilia. By contrast, it would appear important to perform parasitological screening in migrants as soon as possible after their arrival. Since such infestations, if untreated, could result in chronic diseases and complications, and could be transmitted in the host countries, our results have potential implications for public health.

Increase of Vascular Endothelial Growth Factor and Decrease of MCP-1 and Some Updated Epidemiology Aspects of Cystic Echinococcosis Human Cases in Calabria Region.

We aim to investigate some of the pathogenetic mediators of the human echinococcosis and to obtain updated epidemiological findings on cases of echinococcosis in Calabria, Southern Italy. Echinococcosis diagnosis was based on imaging, serological investigations, and molecular assay. Indeed, real-time PCR indicated the presence of G2/G3 genotypes of Echinococcus granulosus complex. Regarding pathogenesis, a relevant novel tool of immune depression should be deemed the reduced level of serum MCP-1. Also, we found a previously unreported VEGF, possibly associated with neovascularization requested by the parasite cyst metabolism. Cytokine profiles suggest a bias of the immunity toward Th2 and Treg responses. Nitric oxide levels exhibited a significant decrease one week after therapy versus basal level measured before surgery and/or chemotherapy. An increase of serum total IgE class and IgG4 subclass was found in Echinococcus-positive patients versus controls. Our data demonstrated an endemic spreading, at least in the province of Catanzaro and neighboring Calabria territories, for such parasitosis with the novel issue of the number of female overcoming male cases. In conclusion, the novel findings of this study were the increased VEGF and the reduced serum MCP-1 in the studied cases, as well as the number of Echinococcus-infected females overcoming the infected males.

Six years genotype distribution of Human Papillomavirus in Calabria Region, Southern Italy: a retrospective study.

BACKGROUND: Although analysis of the Human papillomavirus (HPV) genotype spread in a particular area has a crucial impact on public health and prevention programmes, there is a lack of epidemiological data regarding HPV in the Calabria region of Italy. We therefore update information on HPV age/genotype distribution by retrospectively analysing a cohort of women, with and without cervical lesions, living in Calabria, who underwent HPV DNA testing; moreover, we also evaluated HPV age/genotype distribution in a subset of patients with cervical lesions. METHODS: Cervical scrape specimens obtained from 9590 women (age range 20-75 years) from January 2010 to December 2015 were tested for HPV DNA. Viral types were genotyped by Linear Array HPV Genotyping® test (Roche, USA) at the Clinical Microbiology Operative Unit of six hospitals located in four provinces of the Calabria region. Cervical scrape specimens were also used to perform Pap smears for cytological analysis in a subset of 405 women; cytological classification of the samples was performed according to the Bethesda classification system. RESULTS: A total of 2974 women (31%) (C.I. 95% 30.09-31.94) were found to be HPV DNA positive for at least one (57.3%) or several (42.7%) HPV genotypes. Of single genotype HPV infections, 46.5% and 36.4 % were classed as high-risk (HR, Group 1) and low-risk (LR, Group 3) respectively, while 16.9% were classed as probably/possibly carcinogenic and 0.2% undetermined risk. Stratified by age, total HPV distribution, showed the highest prevalence within the range 30-39 years (37.2%), while single genotype infection distribution displayed a peak in women from the age range 20-29 years (37.5%). The most common high-risk HPV type was HPV 16 (19.1%), followed by HPV 31 (9.1%). CONCLUSIONS: We provide epidemiological data on HPV age/genotype distribution in women living in the Calabria region with or without cytological abnormalities, further to the enhancement of HPV screening/prevention programmes for the local population.

Diagnosis and follow-up of Bartonella henselae infection in the spleen of an immunocompetent patient by real-time quantitative PCR.

Systemic Bartonella henselae infections are unusual in immunocompetent adults. However, here we report one such case of bartonellosis in a 34-year-old patient, who presented with fever and multinodular splenomegaly. We also describe a novel method of identifying Bartonella henselae by real-time quantitative polymerase chain reaction and sequencing of amplified products. This could prevent splenic bartonellosis being mistaken for lymphoma and thereby avert unnecessary splenectomy.

Human papillomavirus type 16 E5 protein induces expression of beta interferon through interferon regulatory factor 1 in human keratinocytes.

Crucial steps in high-risk human papillomavirus (HR-HPV)-related carcinogenesis are the integration of HR-HPV into the host genome and loss of viral episomes. The mechanisms that promote cervical neoplastic progression are, however, not clearly understood. During HR-HPV infection, the HPV E5 protein is expressed in precancerous stages but not after viral integration. Given that it has been reported that loss of HPV16 episomes and cervical tumor progression are associated with increased expression of antiviral genes that are inducible by type I interferon (IFN), we asked whether E5, expressed in early phases of cervical carcinogenesis, affects IFN-ß signaling. We show that the HPV type 16 (HPV16) E5 protein expression per se stimulates IFN-ß expression. This stimulation is specifically mediated by the induction of interferon regulatory factor 1 (IRF-1) which, in turn, induces transcriptional activation of IRF-1-targeted interferon-stimulated genes (ISGs) as double-stranded RNA-dependent protein kinase R (PKR) and caspase 8. Our data show a new and unexpected role for HR-HPV E5 protein and indicate that HPV16 E5 may contribute to the mechanisms responsible for cervical carcinogenesis in part via stimulation of IFN-ß and an IFN signature, with IRF-1 playing a pivotal role. HPV16 E5 and IRF-1 may thus serve as potential therapeutic targets in HPV-associated premalignant lesions.

Bartonella quintana-induced apoptosis inhibition of human endothelial cells is associated with p38 and SAPK/JNK modulation and with stimulation of mitosis.

Previous studies demonstrated that live Bartonella quintana often induces angioproliferative lesions in humans. It modulates endothelial cell apoptotic and inflammatory patterns, thus inducing a very early overexpression of caspase 8 and Apaf-1 and increasing mRNA production of TNF-alpha, interleukin-8, and E-selectin. However, starting at 10 hours postinfection, the bacteria provoke antiapoptotic effects that induce an increase of bcl-2 gene transcription. To gain further insight into the cellular mechanisms that regulate apoptosis, survival and proliferation, we studied the modulation of mitogen-activated protein kinase (MAPK) and the activation state of cdc2 kinase, which regulates progression into mitosis. Confocal microscopy findings indicated a maximum rate of Bartonella entry into host cells between postinfection hours 6 and 10. Live bacteria caused substantially higher apoptosis of human umbilical vein endothelial cells-cryopreserved (HUVEC-C) than heat- and trypsin-inactivated microorganisms. During the first 6 hours postinfection, B. quintana triggered a peak of apoptosis, induced activation of p38 MAPK and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), with bacterial clusters appearing at the cellular surface of the HUVEC-C. However, at 8 to 24 hours postinfection, B. quintana was internalized and inhibited proapoptotic signals such as p38 MAPK and SAPK/JNK while inducing antiapoptotic signals. Indeed, expression of the bcl-2 gene and the increase of the bcl-2 kinase active form was concomitant to activation of mitosis, as shown by cdc2 protein activation. These data thus suggest that mechanisms that induce mitotic activity and inhibit apoptotic signals may contribute to the ability of B. quintana to cause vascular proliferation.

Bartonella quintana lipopolysaccharide effects on leukocytes, CXC chemokines and apoptosis: a study on the human whole blood and a rat model.

Bartonella quintana, an emerging gram-negative pathogen, may cause trench fever, endocarditis, cerebral abscess and bacillary angiomatosis usually with the absence of septic shock in humans. B. quintana lipopolysaccharide (LPS), a deep rough endotoxin with strong reactivity in the limulus amebocyte lysate (LAL)-assay, was studied in human whole blood and in a rat model. A significant (P<0.05) increase of interleukin-8 (IL-8) concentration, comparable to the level induced by enterobacterial LPS, was stimulated in the human whole blood by B. quintana LPS. Isolated human neutrophils delayed their apoptotic behavior in the presence of B. quintana LPS. In the rat, B. quintana LPS induced a significant (P<0.001) increase in white blood cell count, both 30 and 60 min after intravenous injection. Such leukocytosis was inhibited by pretreatment with prazosin, an alpha-adrenergic antagonist. B. quintana LPS did not significantly change heart rate (HR), hematocrit (HCT) and platelet count in the above reported in vivo model, and regarding mean blood pressure (MAP) only a very early (5 min after LPS) and mild (yet significant) hypotension was observed. In contrast, a long-lasting decrease of MAP was found in Salmonella minnesota R595 LPS-treated animals. Blood TNFalpha levels did not change significantly from the baseline in rats injected with either saline or with B. quintana LPS, on the contrary S. minnesota R595 LPS-injected animals showed substantial increase of TNFalpha levels up to 2924 pg/ml at 60 min after LPS injection. B. quintana LPS as well as Salmonella LPS-injected rats exhibited an increase of the blood levels of GRO/CINC-1, particularly at 240 min after LPS administration. Apical part of rat gut villi showed several TUNEL-positive cells in tissue sections from B. quintana LPS-treated animals. Taken together, our data demonstrates that B. quintana LPS is able to selectively stimulate some inflammatory mediators. B. quintana LPS-induced leukocytosis appears mediated by an alpha-adrenergic receptor. The delayed apoptotic process of leukocytes and the chemokine increase may explain the apoptotic cells found in the rat gut and the inflammatory reactions in some human Bartonella diseases. This peculiar inflammatory pattern induced by B. quintana LPS, may partially account for the lack of severe septic shock, observed in human B. quintana infections.

In vitro Bartonella quintana infection modulates the programmed cell death and inflammatory reaction of endothelial cells.

Bartonella quintana is an epicellular bacterium, which in vivo as well as in vitro, invades endothelial cells and develops within them inducing proliferative effects that play a pivotal role in neovascular manifestation of this disease. We investigated the effect of live Bartonella quintana and its LPS on apoptosis and inflammatory response in HUVEC-C, an endothelial cell line. The kinetics of the programmed cell death of Bartonella quintana-infected HUVEC-C showed a peculiar course. Even if early during infection apoptosis reached a peak after 6 h, later on apoptosis was inhibited. Such apoptosis inhibition was not observed during Bartonella quintana lipopolysaccharide treatment because LPS-stimulated HUVEC-C did progress to cell death. Evaluation of multiple cell signal transduction pathways revealed an overexpression of Apaf 1 and caspase 8 in HUVEC-C after 2 h of infection, and of bcl-2 starting from 10 h post Bartonella quintana infection. Moreover, Bartonella quintana and its LPS showed a different effect on the activation of genes involved in inflammatory response as revealed by molecular analysis of host cells. Bartonella quintana appears to be able to inhibit programmed cell death, inducing intracellular signals leading to survival and proliferation through the bcl-2 gene, despite the early increase of inflammatory status induced in endothelial cells. This mechanism, together with a poor endotoxin ability to stimulate strong inflammatory response, could contribute to the capability of the bacteria to persist intracellularly, causing chronic disease and producing neovascular manifestations.