Long Term Norovirus Infection in a Patient with Severe Common Variable Immunodeficiency.

Norovirus is the most common cause of acute non-bacterial gastroenteritis. Immunocompromised patients can become chronically infected, with or without symptoms. In Europe, common variable immunodeficiency (CVID) is one of the most common inborn errors of immunity. A potentially severe complication is CVID-associated enteropathy, a disorder with similar histopathology to celiac disease. Studies suggest that chronic norovirus infection may be a contributor to CVID enteropathy, and that the antiviral drug ribavirin can be effective against norovirus. Here, a patient with CVID-like disease with combined B- and T-cell deficiency, had chronic norovirus infection and enteropathy. The patient was routinely administered subcutaneous and intravenous immunoglobulin replacement therapy (SCIg and IVIg). The patient was also administered ribavirin for ~7.5 months to clear the infection. Stool samples (collected 2013-2016) and archived paraffin embedded duodenal biopsies were screened for norovirus by qPCR, confirming a chronic infection. Norovirus genotyping was done in 25 stool samples. For evolutionary analysis, the capsid (VP1) and polymerase (RdRp) genes were sequenced in 10 and 12 stool samples, respectively, collected before, during, and after ribavirin treatment. Secretor phenotyping was done in saliva, and serum was analyzed for histo-blood group antigen (HBGA) blocking titers. The chronic norovirus strain formed a unique variant subcluster, with GII.4 Den Haag [P4] variant, circulating around 2009, as the most recent common ancestor. This corresponded to the documented debut of symptoms. The patient was a secretor and had HBGA blocking titers associated with protection in immunocompetent individuals. Several unique amino acid substitutions were detected in immunodominant epitopes of VP1. However, HBGA binding sites were conserved. Ribavirin failed in treating the infection and no clear association between ribavirin-levels and quantity of norovirus shedding was observed. In conclusion, long term infection with norovirus in a patient with severe CVID led to the evolution of a unique norovirus strain with amino acid substitutions in immunodominant epitopes, but conservation within HBGA binding pockets. Regularly administered SCIg, IVIg, and ~7.5-month ribavirin treatment failed to clear the infection.

How familiar are we with decision-making concerning the treatment of perforation after endoscopic mucosal resection (EMR) in the colon? A case report.

Background and study aims We describe a case of perforation after colonic endoscopic mucosal resection (EMR) that was treated conservatively. We would like to highlight the importance of decision-making mainly based on the endoscopist's point of view in combination with the surgical consultation. Although the radiological imaging is always needed, it cannot solely lead to a decision for operation. Intraperitoneal gas in computed tomography is not always associated with a hole in the endoscopic field and could be possibly explained from a "balloon" phenomenon. The amount of extraluminal air after an EMR does not correlate reciprocally with patient's pain after the procedure. Even though perforation is a radiological diagnosis and endoscopists should be aware of the common post-EMR radiological findings, the surgical examination is mandatory and should be coupled with the endoscopic opinion in order to guide appropriately the treatment in patients with acute pain.

Effect of oral diclofenac intake on faecal calprotectin.

BACKGROUND: NSAIDs are a known source of increased faecal calprotectin (FC) levels. Currently, there is a lack of knowledge about how long it takes for an increased FC level to return to normal after NSAID intake. OBJECTIVE: The aim was to investigate how oral diclofenac intake affects FC levels and assess how long it takes for an increased FC level to return to normal after oral diclofenac intake. MATERIAL AND METHODS: Thirty healthy volunteers received diclofenac 50 mg three times daily for 14 days. Participants provided a stool sample on Days 0, 2, 4, 7, 14 during intake and Days 17, 21, 28 after discontinuation. FC levels were then followed at 7-day intervals until normalization. RESULTS: During diclofenac intake, eight participants (27%) had FC levels exceeding the upper limit of normal (median, 76 µg/g; range, 60-958 µg/g), corresponding to 8.3% of measurements. FC was not constantly increased and became normal in most participants during diclofenac intake. FC levels were on average significantly higher during intake (M = 9.5, interquartile range (IQR) = 13.4) than on baseline (M = 7.5, IQR = 0.0), p = 0.003. After discontinuation, two participants had increased FC on Days 17 and 21, respectively. No significant differences in FC levels were found between baseline and measurements after discontinuation. Two weeks after discontinuation, all participants had normal FC levels. CONCLUSIONS: Short-term oral diclofenac intake is associated with increased FC levels. However, the likelihood of an increased test result is low. Our results suggest that 2 weeks of diclofenac withdrawal is sufficient to get an uninfluenced FC test result.

Sphingolipids in human ileostomy content after meals containing milk sphingomyelin.

BACKGROUND: Sphingomyelin occurs in modest amounts in the diet, in sloughed mucosal cells, and in bile. It is digested by the mucosal enzymes alkaline sphingomyelinase and ceramidase. In humans, alkaline sphingomyelinase is also secreted in bile. The digestion of sphingomyelin is slow and incomplete, which has been linked to the inhibition of cholesterol absorption and colonic carcinogenesis. OBJECTIVE: We evaluated whether the supply of moderate amounts of milk sphingomyelin increases the exposure of the colon to sphingomyelin and its metabolites. DESIGN: Two experimental series were performed. In experiment A, we measured the content of sphingomyelin and ceramide in human ileostomy content by HPLC during 8 h after consumption of a test meal containing 250 mg milk sphingomyelin. In experiment B, we measured the molecular species of sphingomyelin and ceramide by HPLC-tandem mass spectrometry after doses of 50, 100, or 200 mg sphingomyelin. RESULTS: In experiment A, the average increase in ileostomy content of ceramide plus sphingomyelin amounted to 19% of the fed dose of sphingomyelin. In experiment B, the output of C-22:0-sphingomyelin, C-23:0-sphingomyelin, C-24:0-sphingomyelin, and sphingosine increased significantly, and palmitoyl-sphingomyelin increased proportionally less. Outputs and concentrations of palmitoyl-ceramide and sphingosine showed great individual variation, and stearoyl-sphingomyelin and stearoyl-ceramide did not increase after the meals. Although the output of long-chain sphingomyelin species increased significantly, the data indicated that >81% of all measured sphingomyelin species had been digested. CONCLUSIONS: Humans digest and absorb most of the sphingomyelin in normal diets. The amount of sphingolipid metabolites to which the colon is exposed can, however, be influenced by realistic amounts of dietary sphingomyelin.