Giardiasis

Mimics of Crohn's Disease

Crohn's disease is a chronic inflammatory disease that can affect any portion of the gastrointestinal tract. Associated symptoms can vary based on the severity of disease, extent of involvement, presence of extraintestinal manifestations, and development of complications. Diagnosis is based on a constellation of findings. Many diseases can mimic Crohn's disease and lead to diagnostic conundrums. These include entities associated with the gastrointestinal luminal tract, vascular disease, autoimmune processes, various infections, malignancies and complications, drug- or treatment-induced conditions, and genetic diseases. Careful consideration of possible causes is necessary to establish the correct diagnosis.

Role of Polymerase Chain Reaction in Stool and Duodenal Biopsy for Diagnosis of Giardiasis in Patients with Persistent/Chronic Diarrhea

BACKGROUND

Giardia duodenalis is a common cause of chronic diarrhea especially in tropical countries. Diagnosis is based on microscopy (three stool samples) for trophozoites/cysts. Role of stool or duodenal biopsy PCR as a diagnostic method needs to be defined. We conducted a prospective study to determine the diagnostic characteristics of G. duodenalis stool and duodenal biopsy PCR in comparison to stool microscopy (reference standard). Later, we compared other techniques with stool PCR, considering it as new reference standard and characterized the type of Giardia assemblage.

METHODS

G. duodenalis stool nested PCR was first evaluated using 40 positive controls and 50 negative controls considering stool microscopy as reference standard. Patients with chronic diarrhea (n = 100) were evaluated by stool microscopy and nested PCR. In 30 patients in whom upper gastrointestinal endoscopy was performed, duodenal biopsy samples were obtained and evaluated by histopathology, imprint cytology, and nested PCR. The type of Giardia assemblage was detected by assemblage-specific PCR.

RESULTS

Stool nested PCR was found to have sensitivity and specificity of 100% and 94%, respectively, compared to stool microscopy. In patients with chronic diarrhea, 48% had evidence of Giardia infection. Stool microscopy detected 65%, stool PCR detected an additional 27%, and duodenal biopsy PCR detected an additional 8% of cases. The commonest assemblage found was assemblage B. Clinical and demographic characteristics were similar in patients harboring either assemblage A or B.

CONCLUSION

Stool PCR is more sensitive than stool microscopy. By utilizing stool microscopy, stool nested PCR, and duodenal biopsy PCR in sequential manner, diagnostic yield can be increased.

Improving basic skills in celiac-like disease diagnosis: a case report

BACKGROUND

The diagnosis of Coeliac disease (CD) requires a combination of sign/symptoms, positivity of specific antibodies and duodenal histological evidence of villous atrophy. Duodenal villous atrophy, despite representing the CD landmark, is not specific since it is found in many gastrointestinal disorders. Giardiasis is one of the most common human intestinal protozoan infestations in industrialized countries whose histological duodenal mucosa damage could mimic that of CD. The present report shows how a wise clinical and laboratory assessment led us shortly to a correct diagnosis.

CASE PRESENTATION

A 42-year-old outpatient woman without previous significant gastrointestinal diseases, was referred with dyspeptic symptoms, fatigue and mild diarrhea from 4 months. Her first investigations including immunoglobulin A (IgA) anti-tissue transglutaminase antibodies (anti-tTG) and stool parasitological and cultural analysis were negative. An esophagogastroduodenoscopy (EGDS) showed no mucosal alteration. But histology demonstrated a Helicobacter Pylori (HP) pan-gastritis while duodenal mucosa showed villous atrophy consistent with a diagnosis of CD Marsh type 3b. While on gluten-free diet (GFD) the patient didn't experience any improvement of symptoms. Duodenal biopsies were then reviewed showing the presence of trophozoites of Giardia on the luminal surface of the duodenal wall and at the same time, a second stool examination revealed the presence of trophozoites and cysts of Giardia. Treated with metronidazole, 500 mg twice daily for 6 days the patient reduced diarrhea after few days. After about 2 months of GFD she was invited to discontinue it. At the same time stool examination was repeated with negative results. She subsequently performed eradication for Hp with triple therapy (Pylera®). Around 6 months later, the patient did not complain any gastrointestinal symptoms. Serological tests were normal and at a follow-up EGDS, duodenal mucosa had normal histology with normal finger-like villi and absence of Giardia trophozoites.

CONCLUSION

This case report shows how CD diagnosis can sometimes be manifold. Intestinal villous atrophy alone may not automatically establish a diagnosis of CD. In the present case the clinical scenario could be fully explained by giardiasis. Indeed, different diagnostic tools and a multi-step approaches have been used to determine the final correct diagnosis.

First report on Giardia duodenalis assemblage F in Slovakian children living in poor environmental conditions

BACKGROUND

Giardiasis is one of the most common gastrointestinal infections of humans and animals attributable to complex of eight morphologically identical genetic assemblages, further divided into sub-assemblages. Disease is common for a wide range of hosts and genetic characterization is needed for better understanding of multifaceted epidemiology for this protozoan parasite. The aim of this study was to identify genetic heterogeneity in assemblages and sub-assemblages of Giardiaduodenalis circulating among the children population living in deprived socioeconomic conditions.

METHODS

A total of 333 stool samples from children in eastern Slovakia were collected during the period of 2015-2016 and analysed by molecular methods. Molecular characterization of G. duodenalis was performed by sequence analysis of triose phosphate isomerase gene (tpi) and glutamate dehydrogenase gene (gdh).

RESULTS

G. duodenalis DNA was detected in 21 samples (6.3%), out of which 14 isolates (66.7%) belonged to assemblage B, 4 isolates (19.0%) to sub-assemblage AII and 3 isolates (14.3%) corresponded to assemblage F. As regards the determination of sub-assemblages of assemblage B, 4 isolates were characterized as sub-assemblage BIII and 6 isolates as sub-assemblage BIV.

CONCLUSION

This study is the first finding of cat specific assemblage F in man not only in Slovakia, but also in Europe. The absence of molecular data about G. duodenalis in companion animals in Slovakia establishes a strong need for further investigation for potential sources of giardiasis and understanding the epidemiology will help to improve the preventive strategies in eradication of infection in this population.

Detection of Giardia intestinalis in water samples collected from natural water reservoirs and wells in northern and north-eastern Poland using LAMP, real-time PCR and nested PCR

Giardia intestinalis is a protozoan parasite, transmitted to humans and animals by the faecal-oral route, mainly through contaminated water and food. Knowledge about the distribution of this parasite in surface water in Poland is fragmentary and incomplete. Accordingly, 36 environmental water samples taken from surface water reservoirs and wells were collected in Pomerania and Warmia-Masuria provinces, Poland. The 50 L samples were filtered and subsequently analysed with three molecular detection methods: loop-mediated isothermal amplification (LAMP), real-time polymerase chain reaction (real-time PCR) and nested PCR. Of the samples examined, Giardia DNA was found in 15 (42%) samples with the use of LAMP; in 12 (33%) of these samples, Giardia DNA from this parasite was also detected using real-time PCR; and in 9 (25%) using nested PCR. Sequencing of selected positive samples confirmed that the PCR products were fragments of the Giardia intestinalis small subunit rRNA gene. Genotyping using multiplex real-time PCR indicated the presence of assemblages A and B, with the latter predominating. The results indicate that surface water in Poland, as well as water taken from surface wells, may be a source of Giardia strains which are potentially pathogenic for humans. It was also demonstrated that LAMP assay is more sensitive than the other two molecular assays.

First detection and genotyping of Giardia intestinalis in stool samples collected from children in Ghazni Province, eastern Afghanistan and evaluation of the PCR assay in formalin-fixed specimens

It is estimated that faecal-orally transmitted diseases are common in Afghanistan, as a consequence of poor hygienic standards of life and widespread contamination of water and food with both human and animal faeces. However, there is little information in the literature concerning infections caused by intestinal parasites in the Afghan population. In this study, we report the occurrence of Giardia intestinalis assemblages (A and B) in formalin-fixed stool samples collected from 245 Afghan schoolchildren living in Ghazni Province in eastern Afghanistan. Detection of the parasite’s DNA and genotyping was performed using real-time PCR, specific to the β-giardin gene of G. intestinalis. Positive results were recorded in 52 (21.2%) samples. Genotyping was successful in 39 faecal samples and showed the predominance of assemblage B of G. intestinalis in this population (15 assemblage A and 24 assemblage B). Co-infection with both genotypes A and B was detected in four samples. Additionally, we evaluated the effect of 10% buffered formalin fixative on the detection of G. intestinalis DNA using real-time PCR and nested PCR characterised by different lengths of PCR products (74 and 479 bp, respectively). The human faeces containing the Giardia cysts were tested for 16 weeks. Amplification of G. intestinalis DNA with real-time PCR was possible up to 6 weeks of preservation of stool sample in formalin, compared to only 2 weeks with nested PCR. This suggests that real-time PCR is a more suitable tool in cases where stool samples have to be kept in formalin for longer periods of time.

Prevalence and Predictors of Giardia in the United States

BACKGROUND

Infection with Giardia lamblia is a common cause of diarrheal disease in the developing and industrialized world.

AIMS

We aimed to assess the prevalence of giardiasis in the United States (US) among patients with duodenal biopsies, investigating demographic and clinical factors associated with this condition.

METHODS

We conducted a cross-sectional study of patients with duodenal biopsies submitted to a national pathology laboratory between January 2, 2008, and December 31, 2015. The prevalence of giardiasis was calculated and categorized by the following patient sociodemographic and clinical data: age, sex, ethnicity, endoscopy indication, season, year, urban-rural setting, region, and presence of H. pylori and atrophic gastritis.

RESULTS

Among all patients (n = 432,813), the mean age was 52.2 years. The prevalence of giardiasis was 0.11%. Patients with giardiasis were more likely to be male (57.8 vs. 34.1%, p < 0.0001). Among patients who had a gastric biopsy (n = 363,788), those with giardiasis were more likely to be colonized with H. pylori (25.7 vs. 9.4%, p < 0.0001). There was no statistically significant association with age, endoscopy indication, urban-rural setting, ethnicity, season, or the presence of atrophic gastritis. On multivariate analysis, male sex, Southern region, and the presence of H. pylori were independently associated with giardiasis.

CONCLUSIONS

To our knowledge, this is the largest study to date to assess predictors of giardiasis in the US. We found that male sex, being colonized with H. pylori, and residing in the Southern US are independently associated with giardiasis infection.

Stem-Loop RT-qPCR as an Efficient Tool for the Detection and Quantification of Small RNAs in Giardia lamblia

Stem-loop quantitative reverse transcription PCR (RT-qPCR) is a molecular technique used for identification and quantification of individual small RNAs in cells. In this work, we used a Universal ProbeLibrary (UPL)-based design to detect-in a rapid, sensitive, specific, and reproducible way-the small nucleolar RNA (snoRNA) GlsR17 and its derived miRNA (miR2) of Giardia lamblia using a stem-loop RT-qPCR approach. Both small RNAs could be isolated from both total RNA and small RNA samples. Identification of the two small RNAs was carried out by sequencing the PCR-amplified small RNA products upon ligation into the pJET1.2/blunt vector. GlsR17 is constitutively expressed during the 72 h cultures of trophozoites, while the mature miR2 is present in 2-fold higher abundance during the first 48 h than at 72 h. Because it has been suggested that miRNAs in G. lamblia have an important role in the regulation of gene expression, the use of the stem-loop RT-qPCR method could be valuable for the study of miRNAs of G. lamblia. This methodology will be a powerful tool for studying gene regulation in G. lamblia, and will help to better understand the features and functions of these regulatory molecules and how they work within the RNA interference (RNAi) pathway in G. lamblia.

A Prospective Longitudinal Cohort to Investigate the Effects of Early Life Giardiasis on Growth and All Cause Diarrhea

BACKGROUND

Growth stunting in children under 2 years of age in low-income countries is common. Giardia is a ubiquitous pathogen in this age group but studies investigating Giardia's effect on both growth and diarrhea have produced conflicting results.

METHODS

We conducted a prospective longitudinal birth cohort study in Dhaka, Bangladesh, with monthly Giardia and continuous diarrheal surveillance.

RESULTS

629 children were enrolled within the first 72 hours of life, and 445 completed 2 years of the study. 12% of children were stunted at birth with 57% stunted by 2 years. 7% of children had a Giardia positive surveillance stool in the first 6 months of life, whereas 74% had a positive stool by 2 years. The median time to first Giardia positive surveillance stool was 17 months. Presence of Giardia in a monthly surveillance stool within the first 6 months of life decreased length-for-age Z score at 2 years by 0.4 (95% confidence interval, -.80 to -.001; P value .05) whereas total number of Giardia positive months over the 2-year period of observation did not. Neither variable was associated with weight-for-age Z score at 2 years. In our model to examine predictors of diarrhea only exclusive breastfeeding was significantly associated with decreased diarrhea (P value <.001). Concomitant giardiasis was neither a risk factor nor protective.

CONCLUSIONS

Early life Giardia was a risk factor for stunting at age 2 but not poor weight gain. Presence of Giardia neither increased nor decreased odds of acute all cause diarrhea.

Validation of housekeeping genes as an internal control for gene expression studies in Giardia lamblia using quantitative real-time PCR

The analysis of transcript levels of specific genes is important for understanding transcriptional regulation and for the characterization of gene function. Real-time quantitative reverse transcriptase PCR (RT-qPCR) has become a powerful tool to quantify gene expression. The objective of this study was to identify reliable housekeeping genes in Giardia lamblia. Twelve genes were selected for this purpose, and their expression was analyzed in the wild type WB strain and in two strains with resistance to nitazoxanide (NTZ) and metronidazole (MTZ), respectively. RefFinder software analysis showed that the expression of the genes is different in the three strains. The integrated data from the four analyses showed that the NADH oxidase (NADH) and aldolase (ALD) genes were the most steadily expressed genes, whereas the glyceraldehyde-3-phosphate dehydrogenase gene was the most unstable. Additionally, the relative expression of seven genes were quantified in the NTZ- and MTZ-resistant strains by RT-qPCR, using the aldolase gene as the internal control, and the results showed a consistent differential pattern of expression in both strains. The housekeeping genes found in this work will facilitate the analysis of mRNA expression levels of other genes of interest in G. lamblia.

Predictive value of "Marsh 1" type histology in subjects with suspected cealic disease

INTRODUCTION

The diagnosis of celiac disease (CD) is based on histology in combination with anti-tissue transglutaminase (a-tTG) and anti-endomysial antibodies (EMAs). The increase of intraepithelial lymphocytes defines the Marsh 1 histology that appears not to be specific for CD.

AIM

To explore the positive predictive value (PPV) and clinical relevance of Marsh 1 histology in suspected CD.

METHODS

We carried out an observational prospective study including all consecutive subjects with a Marsh 1 histology. All patients were tested for a-tTG and EMAs. Diagnosis of potential CD was defined in the presence of Marsh 1 with positive a-tTG and EMAs. Patients were investigated for symptoms, CD familial aggregation, other diseases, and current medication.

RESULTS

Sixty-three patients with Marsh 1 were included. Diagnosis of potential CD was made in 23 subjects (36%), so that Marsh 1 histology showed a PPV of 36%. With regard to familial aggregation, patients with potential CD showed a higher frequency of familiarity for CD (60.8% vs. 15.0%; p < 0.01). No significant difference was detected between CD and non-CD in terms of intestinal and extra-intestinal symptoms. We also documented the presence of conditions other than CD in the remaining population: 7 patients (17.5%) with immuno-mediated diseases while 5 patients (12.5%) showed Helicobacter pylori (HP) infection. About medication, 3 patients (7.5%) were on non-steroidal anti-inflammatory drugs, while another 4 (10%) patients were being treated with other drugs.

CONCLUSION

The Marsh 1 type histology is not specific for CD and it can also be associated with immuno-mediated disorders, HP infection, and drugs.

Can Giardia lamblia infection lower the risk of acute diarrhea among preschool children?

There are inconsistent findings concerning the role of Giardia lamblia in pediatric diarrhea. A prospective cohort study of the incidence of acute diarrhea among Israeli Arab preschool children offered the opportunity to examine the association between G. lamblia infection (at baseline) and subsequent diarrhea. Following baseline screening by light microscopy for the presence of Giardia in their stools, a cohort was assembled of 142 children who were followed between October 2003 and August 2004 for the incidence of diarrhea. Surveillance was performed through maternal interviews. At baseline, 21 children tested Giardia-positive. During the prospective surveillance, acute diarrhea occurred less often among Giardia-positive children (9.5%) than among children who were not infected with Giardia (26.5%). G. lamblia infection was associated with lower risk of acute diarrhea; adjusted odds ratio of 0.18 (95% confidence interval 0.04-0.93) (p = 0.041). This prospective study provides additional evidence that Giardia may lower the risk of subsequent acute diarrhea among preschool children.

Detection and genotype analysis of Giardia duodenalis from asymptomatic Hungarian inhabitants and comparative findings in three distinct locations

The transmission route of giardiasis not yet understood and why some infected individuals remain asymptomatic while others become quite ill. The drinking water quality is supposedly responsible for the prevalence of asymptomatic Giardia duodenalis infections in different areas, therefore asymptomatic giardiasis has been investigated in three water supply areas of Hungary: three hundred stool samples from inhabitants of Budapest, Füzér and Mátrafüred were examined by immunological and molecular methods for the presence of G. duodenalis infections. Individuals were asked to fill out a validated questionnaire at the time of stool collection and the interview covered demographic data, family life, education and travel history.In Budapest and in Mátrafüred in one stool sample G. duodenalis Assemblage A, whereas in Füzér once G. duodenalis Assemblage A, once Assemblage B and twice mixed infection were detected. We found higher prevalence rate of 4% of G. duodenalis infections of asymptomatic people in the village Füzér, where the removal of the Giardia cysts of the drinking water treatment plant was not effective. This study throws a light the need to look into the possibility of other risks of Giardia infections such as water transmission routes. To our knowledge, this is the first study evaluating the prevalence of G. duodenalis infections in asymptomatic persons in Hungary.

The clinical significance of duodenal lymphocytosis with normal villus architecture

CONTEXT

The finding of increased intraepithelial lymphocytes with normal villous architecture (Marsh I lesion) is seen in up to 3% of duodenal biopsies. The differential diagnosis includes a wide range of possibilities, including celiac disease, bacterial overgrowth, nonsteroidal antiinflammatory drug damage, reaction to Helicobacter pylori infection, tropical sprue, and chronic inflammatory bowel disease.

OBJECTIVES

To highlight the histologic features of the Marsh I lesion, review the diseases and conditions associated with that finding, and to provide pathologists with a rationale and a template for how to identify and report such cases.

DATA SOURCES

A review of the literature regarding the histologic features and clinical associations of Marsh I lesions.

CONCLUSIONS

Marsh I lesions are a nonspecific finding associated with a number of disease conditions. Historically, between 9% and 40% of cases have been shown to represent celiac disease. Current data do not suggest histologic features to differentiate between diseases associated with this histologic change.

Occurrence and potential health risk of Cryptosporidium and Giardia in the Three Gorges Reservoir, China

The Three Gorges Reservoir (TGR) is the biggest lake in the world and a major water source in China. There is no information about occurrence and impact of Cryptosporidium and Giardia on the aquatic ecosystem. 61 surface water samples from 23 monitoring sites and 5 treated effluent samples were collected and analyzed. Cryptosporidium oocysts and Giardia cysts were found, respectively, in 86.4% and 65.2% of a total of 66 water samples, with high concentrations in treated effluent. The mean percent recovery was 29.14% for oocysts and 34.86% for cysts. A seasonal pattern was observed, with positive samples for Cryptosporidium more frequent in flood period and positive samples for Giardia more frequent in impounding period. Counts of enterococci, fecal coliforms and total coliforms, and turbidity were significantly associated with Cryptosporidium concentration in backwater (water in a main river which is backed up by the Three Gorges Dam) areas of tributaries but not Giardia. High associations were also found between oocyst and cyst in backwater areas of tributaries and cities. The risks of infection and illness due to water consumption in four different exposure routes were estimated. The results showed that swimming in the TGR has the highest infection risk with 1.39 × 10(-3) per time (95% confidence interval (CI): 0.05-600.3 × 10(-5)) for Cryptosporidium and 2.08 × 10(-4) per time (95% CI: 0.05-878.87 × 10(-6)) for Giardia, while directly drinking unboiled tap water treated with the conventional process has the highest morbidity with 524.98 per 100,000 population per year (95% CI: 10.35-2040.26) for Cryptosporidium and 5.89 per 100,000 population per year (95% CI: 0.08-22.67) for Giardia. This study provides new useful information for drinking water plants, health care workers and managers to improve the safety of tap water and deduce the risk of surface water contamination in China.

A systematic review and meta-analysis of the association between Giardia lamblia and endemic pediatric diarrhea in developing countries

We performed a systematic literature review and meta-analysis examining the association between diarrhea in young children in nonindustrialized settings and Giardia lamblia infection. Eligible were case/control and longitudinal studies that defined the outcome as acute or persistent (>14 days) diarrhea, adjusted for confounders and lasting for at least 1 year. Data on G. lamblia detection (mainly in stools) from diarrhea patients and controls without diarrhea were abstracted. Random effects model meta-analysis obtained pooled odds ratios (ORs) and 95% confidence intervals (CIs). Twelve nonindustrialized-setting acute pediatric diarrhea studies met the meta-analysis inclusion criteria. Random-effects model meta-analysis of combined results (9774 acute diarrhea cases and 8766 controls) yielded a pooled OR of 0.60 (95% CI, .38-.94; P = .03), indicating that G. lamblia was not associated with acute diarrhea. However, limited data suggest that initial Giardia infections in early infancy may be positively associated with diarrhea. Meta-analysis of 5 persistent diarrhea studies showed a pooled OR of 3.18 (95% CI, 1.50-6.76; P < .001), positively linking Giardia with that syndrome. The well-powered Global Enteric Multicenter Study (GEMS) is prospectively addressing the association between G. lamblia infection and diarrhea in children in developing countries.

Analysis of Giardia lamblia interactions with polymer surfaces using a microarray approach

The interaction of the waterborne protozoan parasite, Giardia lamblia, with polymeric materials was investigated by microarray screening of 652 polymers. Polymers were identified which either bound G. lamblia cysts or prevented their binding. Correlation of material properties such as wettability and surface roughness with cyst attachment revealed no influence of these factors upon Giardia adhesion. However, the study of polymer composition allowed the correlation of binding and generation of polymer structure function relationships; glycol and aromatic functionalities appeared to prevent adhesion, whereas secondary amine groups promoted adhesion, in agreement with previous literature. A significant reduction in attachment was observed following both cyst treatments with proteinase K and performing experiments at extremes of pH (2 and 12). It is suggested that proteinase K removes the proteins needed for specific surface interactions, whereas extremes of pH influence either protonation of the polymer or the surface charge of the cysts. The mechanism by which the protozoa attach to polymeric surfaces is proposed to be through ion-pair interactions. Improved understanding of G. lamblia surface interactions could assist in predicting transport and fate behavior in the environment and contribute to better design of water treatment processes, while the polymers identified in this work could find use in sensor applications and membrane filtration.

Use of nitazoxanide for gastrointestinal tract infections: Treatment of protozoan parasitic infection and beyond

The United States Food and Drug Administration has approved the parasiticidal agent nitazoxanide for treatment of diarrhea caused by Giardia lamblia/intestinalis or Cryptosporidium parvum. This novel agent has a broad spectrum of activity against many other gastrointestinal pathogens, including bacteria, roundworms, flatworms, and flukes. Nitazoxanide is used in many areas of the world, especially in Central and South America, as a broad-spectrum parasiticidal agent in adults and children. Nitazoxanide appears to be well tolerated, has a relatively low incidence of adverse effect, and displays no significant known drug-to-drug interactions. Recently, preliminary reports indicate that nitazoxanide may be an effective treatment for Clostridium difficile-associated diarrhea as well. Future work will likely solidify and further expand the role of nitazoxanide in the treatment of a wide range of intestinal pathogens.

Antiparasitic therapy in children

Treatment of parasitic infections in children presents many challenges for the clinician. Although parasitic infections are ubiquitous on a worldwide basis, with an estimated 1 billion persons infected with intestinal helminthes alone, physicians in the United States and other developed countries are often unfamiliar with the management of these diseases. Children are traveling internationally in larger numbers than ever before, however, and emigration from developing countries to the United States and other Western countries is increasing, so clinicians in these countries are confronted more frequently with parasitic diseases from the tropics. This article describes current approaches to antiparasitic therapy. Drugs used in the treatment of more than one type of parasite are presented once in detail, with reference to the detailed description in subsequent sections.

Diagnosis of coeliac disease

The diagnosis of coeliac disease depends on the finding of characteristic, though not specific changes, of intraepithelial lymphocytosis, crypt hyperplasia and various degrees of villous height reduction identified in duodenal biopsies of individuals ingesting a gluten containing diet, together with symptomatic and histologic improvement on gluten withdrawal. Serologic testing has become the main mode of determining who will undergo biopsy. The IgA endomysial antibody and IgA tissue transglutaminase antibody have approximately 90% sensitivity and specificity, though there are reports of lower sensitivity and specificity in the clinical practice setting. This is due to lower titers of these antibodies in the presence of lesser degrees of mucosal damage. The widespread availability of serologic tests for coeliac disease allows the diagnosis to be considered by any physician. Gastroenterologists will be required to interpret the results of serologic tests and perform duodenal biopsies when indicated. Pathologists likewise need to be better acquainted with the more subtle changes of cell mediated immunity within the mucosa that are suggestive of underlying gluten sensitivity.