Point-shear wave elastography generated by acoustic radiation force impulse in chronic pancreatitis.

BACKGROUND: Transcutaneous point-shear wave elastography (p-SWE) performed using an acoustic radiation force impulse can be used to quantify pancreatic stiffness in chronic pancreatitis (CP). We aimed to evaluate its usefulness to diagnose and monitor CP. METHODS: 175 participants were included in this prospective study including patients with CP (n = 65), liver cirrhosis (LC; n = 60), alcohol abuse (n = 10) and healthy controls (n = 40). Point-shear wave elastography of the pancreas was performed and quantified as median shear wave velocity (SWV). In the same way, p-SWE of the spleen served as a marker of portal hypertension. The M-ANNHEIM Severity score was used as global marker for disease activity in CP. RESULTS: Compared to healthy controls, pancreatic SWV was significantly elevated in CP (1.38 vs. 0.96 m/s; p < 0.0001, MWU-test). Pancreatic SWV was increased in alcoholic CP but not in hereditary CP. Receiver operating characteristic analysis revealed 1.2 m/s as the optimal cut-off to identify non-heredity-CP subjects (90% specificity; 81% sensitivity; 92% positive predictive value). Pancreatic SWV correlated significantly with the M-ANNHEIM Severity score, severity of CP-typical complications (both p < 0.05, linear regression analysis), morphological changes of the pancreas and need for hospital treatment (both p < 0.05, MWU-test) but not with exocrine or endocrine insufficiency. Pancreatic SWV >1.7 m/s was identified to predict M-ANNHEIM Severity score ≥11 points. Pancreatic SWV was also elevated in LC (1.42 m/s; p < 0.001), correlating with increased splenic SWV. CONCLUSION: Transcutaneous pancreatic p-SWE represents a bedside, cost-effective and non-invasive tool which adds valuable information to the process of diagnosing and monitoring CP. By portal hypertension, an increased pancreatic SWV must be expected.

Impact of alcohol and smoking cessation on the course of chronic pancreatitis.

OBJECTIVES: Alcohol and nicotine are the two most important risk factors of chronic pancreatitis and they often occur together. It is still unclear how much they influence the severity of the disease and which of the two addictions should be treated with priority. METHODS: We performed a single-center, retrospective, cross-sectional study in a mixed medicosurgical cohort of 870 patients diagnosed with chronic pancreatitis (CP). We analyzed the impact of the drinking pattern and abstinence for alcohol and nicotine on the course of the disease. Patients with alcoholic CP were subdivided in I) patients with "life-time drinking history" (LTDH), II) "current drinkers" with current alcohol abuse without signs of LTDH, and III) "former drinkers" who stopped or reduced alcohol intake dramatically. RESULTS: Compared to patients with LTDH, "former drinkers" had a lower rate of exocrine insufficiency (29% vs. 59%) and pseudocysts (33% vs. 49%), were more often relapse-free (37% vs. 5%) and had less abdominal pain. There was no correlation detected between the quantity of alcohol consumption and the severity or progression of the disease. Regarding nicotine, 29 pack years are the threshold for developing early stage of CP. Under nicotine abstinence, only slightly more patients were relapse-free (37% vs. 22%). In contrast, the cumulative amount of nicotine consumed correlated with overall disease severity and the development of pseudocysts. The need for surgery was increased with odds ratios of 1.8 for both, alcohol and nicotine abuse. CONCLUSIONS: Alcohol cessation in chronic pancreatitis reduces exocrine insufficiency, abdominal pain and local complications. The effect of nicotine cessation is less pronounced in our cohort. However, nicotine abuse represents an important factor for the development of the disease.

Impact of etiology on disease course in chronic pancreatitis.

BACKGROUND: Complications in chronic pancreatitis (CP) can be grouped in inflammatory (ICC) and fibrotic (FCC) clusters and pancreatic insufficiency cluster (PIC). However, the association between etiological risk factors and the development of complication clusters remains obscure. In this study, the impact of the etiology and disease duration on disease onset and development of complications was investigated. METHODS: This cross-sectional study recruited patients with CP from Mannheim/Germany (n = 870), Gießen/Germany (n = 100) und Donetsk/Ukraine (n = 104). Etiological risk factors, disease stage, age at disease onset, complications, need for hospitalization and surgery were noted. RESULTS: In 1074 patients diagnosed with CP, main risk factors were alcohol and nicotine abuse. An earlier onset of the disease was observed upon nicotine abuse (-4.0 years). Alcohol abuse was only associated with an earlier onset of the definite stage of CP. Alcohol abuse was the major risk factor for the development of ICC (p < 0.0001, multiple regression modeling). Abstinence of alcohol reduced ICC, whereas abstinence of nicotine showed no association. PIC correlated with efferent duct abnormalities and the disease duration. In contrast, FCC was mainly dependent on the disease duration (p < 0.0001; t-test). The presence of any complication cluster correlated with the need for surgery (p < 0.01; X2-test). However, only ICC correlated with a prolonged hospital stay (p < 0.05; t-test). CONCLUSIONS: ICC is mainly dependent on alcohol abuse. In contrast, FCC and PIC are mainly dependent on the disease duration. The etiology and disease duration can be used as predictors of the course of disease to provide individual treatment and surveillance strategies.

Transcriptional changes of proteins of the thioredoxin and glutathione systems in Acanthamoeba spp. under oxidative stress - an RNA approach.

The thioredoxin (Trx) and the glutathione (GSH) systems represent important antioxidant systems in cells and in particular thioredoxin reductase (TrxR) has been shown to constitute a promising drug target in parasites. For the facultative protozoal pathogen Acanthamoeba, it was demonstrated that a bacterial TrxR as well as a TrxR, characteristic of higher eukaryotes, mammals and humans is expressed on the protein level. However, only bacterial TrxR is strongly induced by oxidative stress in Acanthamoeba castellanii. In this study, the impact of oxidative stress on key enzymes involved in the thioredoxin and the glutathione system of A. castellanii under different culture conditions and of clinical Acanthamoeba isolates was evaluated on the RNA level employing RT-qPCR. Additionally, the effect of auranofin, a thioredoxin reductase inhibitor, already established as a potential drug in other parasites, on target enzymes in A. castellanii was investigated. Oxidative stress induced by hydrogen peroxide led to significant stimulation of bacterial TrxR and thioredoxin, while diamide had a strong impact on all investigated enzymes. Different strains displayed distinct transcriptional responses, rather correlating to sensitivity against the respective stressor than to respective pathogenic potential. Culture conditions appear to have a major effect on transcriptional changes in A. castellanii. Treatment with auranofin led to transcriptional activation of the GSH system, indicating its role as a potential backup for the Trx system. Altogether, our data provide more profound insights into the complex redox system of Acanthamoeba, preparing the ground for further investigations on this topic.

Title: Modifications transcriptionnelles des protéines des système thiorédoxine et glutathion chez Acanthamoeba spp. sous stress oxydatif ­ une approche par l'ARN. Abstract: Les systèmes de la thiorédoxine (Trx) et du glutathion (GSH) représentent des systèmes antioxydants importants dans les cellules et, en particulier, la thiorédoxine réductase (TrxR) s'est avérée constituer une cible médicamenteuse prometteuse chez les parasites. Pour le pathogène protozoaire facultatif Acanthamoeba, il a été démontré qu'une TrxR bactérienne ainsi qu'une TrxR, caractéristique des eucaryotes supérieurs, des mammifères et des humains, s'expriment au niveau protéique. Cependant, seule la TrxR bactérienne est fortement induite par le stress oxydatif chez Acanthamoeba castellanii. Dans cette étude, l'impact du stress oxydatif sur les enzymes clés impliquées dans la thiorédoxine et le système glutathion d'A. castellanii dans différentes conditions de culture et d'isolats cliniques d'Acanthamoeba a été évalué au niveau de l'ARN en utilisant la RT-qPCR. De plus, l'effet de l'auranofine, un inhibiteur de la thiorédoxine réductase déjà établi comme médicament potentiel chez d'autres parasites, a été étudié sur les enzymes cibles chez A. castellanii. Le stress oxydatif induit par le peroxyde d'hydrogène a conduit à une stimulation significative du TrxR bactérien et de la thiorédoxine tandis que le diamide a eu un fort impact sur toutes les enzymes étudiées. Différentes souches ont affiché des réponses transcriptionnelles distinctes, plutôt corrélées à la sensibilité contre le facteur de stress respectif qu'à leur potentiel pathogène respectif. Les conditions de culture semblent avoir un effet majeur sur les changements transcriptionnels chez A. castellanii. Le traitement à l'auranofine a conduit à une activation transcriptionnelle du système GSH, indiquant son rôle de sauvegarde potentielle pour le système Trx. Dans l'ensemble, nos données fournissent des informations plus approfondies sur le système redox complexe d'Acanthamoeba, préparant le terrain pour de nouvelles investigations sur ce sujet.

Anti-Acanthamoeba disinfection: hands, surfaces and wounds.

Acanthamoebae are facultative parasites causing rare but serious infections such as keratitis and encephalitis and are also known as vectors for several bacterial pathogens, including legionellae and pseudomonads. Acanthamoeba cysts are particularly resilient and enable the amoebae to withstand desiccation and to resist disinfection and therapy. While the search for new therapeutic options has been intensified in the past years, hand and surface disinfectants as well as topical antiseptics for preventing infections have not been studied in detail to date. The aim of this study was to screen well-known and commonly used antimicrobial products in various formulations and different concentrations for their efficacy against Acanthamoeba trophozoites and cysts, including aliphatic alcohols, quaternary ammonium compounds (QACs), peracetic acid (PAA), potassium peroxymonosulfate sulfate (PPMS) and octenidine dihydrochloride (OCT). Of all products tested, OCT and QACs showed the highest efficacy, totally eradicating both trophozoites and cysts within 1 min. The determined 50% effective concentration (EC50) for cysts was 0.196 mg/mL for OCT and 0.119 mg/mL for QACs after 1 min of exposure. PAA and PPMS showed reliable cysticidal efficacies only with prolonged incubation times of 30 min and 60 min, respectively. Aliphatic alcohols generally had limited efficacy, and only against trophozoites. In conclusion, OCT and QACs are potent actives against Acanthamoeba trophozoites and cysts at concentrations used in commercially available products, within contact times suitable for surface and hand disinfection as well as topical antisepsis.