Browsing by Author "Rostami K"

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    Diagnosis of protozoa diarrhoea in Campylobacter patients increases markedly with molecular techniques.
    (Public Library of Science (PLoS), 2023-05-30) Hayman DTS; Garcia-Ramirez JC; Pita A; Velathanthiri N; Knox MA; Ogbuigwe P; Baker MG; Rostami K; Deroles-Main J; Gilpin BJ; Standley C
    Cryptosporidium and Giardia are major causes of diarrhoea globally, and two of the most notified infectious diseases in New Zealand. Diagnosis requires laboratory confirmation carried out mostly via antigen or microscopy-based techniques. However, these methods are increasingly being superseded by molecular techniques. Here we investigate the level of protozoa detection by molecular methods in campylobacteriosis cases missed through antigen-based assays and investigate different molecular testing protocols. We report findings from two observational studies; the first among 111 people during a Campylobacter outbreak and the second during normal surveillance activities among 158 people presenting with diarrhoea and a positive Campylobacter test, but negative Cryptosporidium and Giardia antigen-based test results. The molecular methods used for comparison were in-house end-point PCR tests targeting the gp60 gene for Cryptosporidium and gdh gene for Giardia. DNA extraction was performed with and without bead-beating and comparisons with commercial real-time quantitative (qPCR) were made using clinical Cryptosporidium positive sample dilutions down to 10-5. The Cryptosporidium prevalence was 9% (95% CI: 3-15; 10/111) and Giardia prevalence 21% (95% CI: 12-29; 23/111) in the 111 Campylobacter outbreak patients. The Cryptosporidium prevalence was 40% (95% CI: 32-48; 62/158) and Giardia prevalence 1.3% (95% CI: 0.2-4.5; 2/158) in the 158 routine surveillance samples. Sequencing identified Cryptosporidium hominis, C. parvum, and Giardia intestinalis assemblages A and B. We found no statistical difference in positive test results between samples using end-point PCR with or without bead-beating prior to DNA extraction, or between the in-house end-point PCR and qPCR. The qPCR Ct value was 36 (95% CI: 35-37) for 1 oocyst, suggesting a high limit of detection. In conclusion in surveillance and outbreak situations we found diagnostic serology testing underdiagnoses Cryptosporidium and Giardia coinfections in Campylobacter patients, suggesting the impact of protozoa infections may be underestimated through underdiagnosis using antigen-based assays.
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    Gluten Induces Subtle Histological Changes in Duodenal Mucosa of Patients with Non-Coeliac Gluten Sensitivity: A Multicentre Study
    (MDPI (Basel, Switzerland), 2022-06-15) Rostami K; Ensari A; Marsh MN; Srivastava A; Villanacci V; Carroccio A; Asadzadeh Aghdaei H; Bai JC; Bassotti G; Becheanu G; Bell P; Di Bella C; Bozzola AM; Cadei M; Casella G; Catassi C; Ciacci C; Apostol Ciobanu DG; Cross SS; Danciu M; Das P; Del Sordo R; Drage M; Elli L; Fasano A; Florena AM; Fusco N; Going JJ; Guandalini S; Hagen CE; Hayman DTS; Ishaq S; Jericho H; Johncilla M; Johnson M; Kaukinen K; Levene A; Liptrot S; Lu L; Makharia GK; Mathews S; Mazzarella G; Maxim R; La Win Myint K; Mohaghegh-Shalmani H; Moradi A; Mulder CJJ; Ray R; Ricci C; Rostami-Nejad M; Sapone A; Sanders DS; Taavela J; Volta U; Walker M; Derakhshan M; Witteman B
    Background: Histological changes induced by gluten in the duodenal mucosa of patients with non-coeliac gluten sensitivity (NCGS) are poorly defined. Objectives: To evaluate the structural and inflammatory features of NCGS compared to controls and coeliac disease (CeD) with milder enteropathy (Marsh I-II). Methods: Well-oriented biopsies of 262 control cases with normal gastroscopy and histologic findings, 261 CeD, and 175 NCGS biopsies from 9 contributing countries were examined. Villus height (VH, in μm), crypt depth (CrD, in μm), villus-to-crypt ratios (VCR), IELs (intraepithelial lymphocytes/100 enterocytes), and other relevant histological, serologic, and demographic parameters were quantified. Results: The median VH in NCGS was significantly shorter (600, IQR: 400−705) than controls (900, IQR: 667−1112) (p < 0.001). NCGS patients with Marsh I-II had similar VH and VCR to CeD [465 µm (IQR: 390−620) vs. 427 µm (IQR: 348−569, p = 0·176)]. The VCR in NCGS with Marsh 0 was lower than controls (p < 0.001). The median IEL in NCGS with Marsh 0 was higher than controls (23.0 vs. 13.7, p < 0.001). To distinguish Marsh 0 NCGS from controls, an IEL cut-off of 14 showed 79% sensitivity and 55% specificity. IEL densities in Marsh I-II NCGS and CeD groups were similar. Conclusion: NCGS duodenal mucosa exhibits distinctive changes consistent with an intestinal response to luminal antigens, even at the Marsh 0 stage of villus architecture.
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    The differential diagnoses for severe enteropathy or severely damaged small intestinal mucosa
    (Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences (RIGLD), affiliated to Shahid Beheshti University of Medical Sciences, 2023-04-21) Jian CLA; Hayman DTS; Lockett B; Rostami K
    Aim: The aim of this study was to explore the aetiology of severe duodenal mucosal abnormality in consecutive patients who underwent gastroscopy and duodenal biopsy over the past 10 years. Background: A range of differential diagnoses have been reported for severe duodenal architectural distortion. Methods: Clinical and laboratory data of all the patients with severe duodenal architectural distortion diagnosed at MidCentral District Health Board (DHB), New Zealand were collected and statistically analysed. Ninety-five percent confidence intervals (CI) are shown. Results: Between September 2009 and April 2019, 229 patients were diagnosed with severe enteropathy. The median patient age was 41 years (range 6-83 years). Two hundred and twenty-four of these patients (97.8%, 95.0-99.3%) were diagnosed with coeliac disease (CeD), with one of these patients having gluten induced T-cell lymphoma. From the remaining five patients, one had a diagnosis of tropical sprue and four did not have a clear aetiology. There were 180 patients from 191 (94.2%, 89.9-97.1%) with at least one positive coeliac marker, all with a diagnosis of CeD. Eleven patients (5.8% of 191, 2.9-10.1%) had negative markers for both tissue transglutaminase IgA (tTG-IgA) and IgA-endomysial antibodies (EMA-IgA) with six having a diagnosis of seronegative CeD. Conclusion: Although the spectrum of histological changes in CeD may range from normal to a flat mucosa, severe duodenal architectural distortion seems to occur mainly in CeD. Idiopathic enteropathy was recorded as the second but by far less frequent presentation of severe enteropathy. This study highlights that infection and other aetiologies are rarely implicated in severe enteropathy, with one case (0.4%) of refractory CeD/T-cell lymphoma.