OTHR-41. Amplification of the PLAG family genes – PLAGL1 and PLAGL2 – is a key feature of a novel embryonal CNS tumor type

Pediatric central nervous system (CNS) tumors differ substantially from their adult counterparts, are marked by considerable molecular and clinical heterogeneity, and diagnosis through histopathology alone can be challenging. Using DNA methylation-based CNS tumor classification in combination with copy number and RNAseq analysis, we identify a rare, novel pediatric CNS tumor type (n=32) which is characterized by focal high-level amplification and consecutive overexpression of one of the PLAG family genes – PLAGL1 or PLAGL2. It is epigenetically divergent from other known tumor types such as high-grade gliomas, medulloblastomas, embryonal tumors, or CNS sarcomas. The wide range of original histopathologic diagnosis rendered attests to their polyphenotypic nature in terms of morphology. We suggest that these tumors may arise from early to intermediate neural progenitor cells with some neuronal commitment. Using ChIPseq data, we show that both PLAGL1 and PLAGL2 act as transcription factors for: i) the oncogenic kinase RET, a potential drug target, that was overexpressed in our cohort; ii) components of the Wnt/β-Catenin pathway; iii) a set of imprinted genes, reported to regulate the imprinted gene network in mouse models, that was deregulated in the PLAGL-amplified tumors. Consequently, a 250-gene expression PLAGL-signature indicated dysregulation of imprinting control and differentiation/development as a prominent feature. We report differences regarding age and sex distribution between PLAGL1- and PLAGL2-amplified tumors and shed light on differences in clinical behavior and outcomes between these subtypes in male and female patients. PLAGL1-amplified tumors were more prevalent in school-age children and teenagers, while PLAGL2-amplified cases occurred in very young patients. Kaplan-Meier analysis showed a trend towards a more favorable outcome in patients with PLAGL1-amplified tumors and in female patients. Survival rates remained constant after 5 years with a five-/ten-year overall survival of 75% for PLAGL1, 24% for PLAGL2, 18% for male patients, and 88% for female patients.

Lack of association of MYO9B genetic variants with coeliac disease in a British cohort

BACKGROUND AND AIMS

Development of coeliac disease involves an interaction between environmental factors (especially dietary wheat, rye, and barley antigens) and genetic factors (there is strong inherited disease susceptibility). The known human leucocyte antigen (HLA)-DQ2 and -DQ8 association explains only a minority of disease heritability. A recent study in the Dutch population suggested that genetic variation in the 3' region of myosin IXB (MYO9B) predisposes to coeliac disease. MYO9B is a Rho family GTPase activating protein involved in epithelial cell cytoskeletal organisation. MYO9B is hypothesised to influence intestinal permeability and hence intestinal antigen presentation.

METHODS

Four single nucleotide polymorphisms were chosen to tag all common haplotypes of the MYO9B 3' haplotype block (exons 15-27). We genotyped 375 coeliac disease cases and 1366 controls (371 healthy and 995 population based). All individuals were of White UK Caucasian ethnicity.

RESULTS

UK healthy control and population control allele frequencies were similar for all MYO9B variants. Case control analysis showed no significant association of any variant or haplotype with coeliac disease.

CONCLUSIONS

Genetic variation in MYO9B does not have a major effect on coeliac disease susceptibility in the UK population. Differences between populations, a weaker effect size than originally described, or possibly a type I error in the Dutch study might explain these findings.

Variation in the CTLA4/CD28 gene region confers an increased risk of coeliac disease

Susceptibility to coeliac disease involves HLA and non-HLA-linked genes. The CTLA4/CD28 gene region encodes immune regulatory T-cell surface molecules and is a strong candidate as a susceptibility locus. We evaluated CTLA4/CD28 in coeliac disease by genetic linkage and association and combined our findings with published studies through a meta-analysis. 116 multiplex families were genotyped across CTLA4/CD28 using eight markers. The contribution of CTLA4/CD28 to coeliac disease was assessed by non-parametric linkage and association analyses. Seven studies were identified that had evaluated the relationship between CTLA4/CD28 and coeliac disease and a pooled analysis of data undertaken. In our study there was evidence for a relationship between variation in the CTLA4/CD28 region and coeliac disease by linkage and association analyses. However, the findings did not attain formal statistical significance (p = 0.004 and 0.039, respectively). Pooling findings with published results showed significant evidence for linkage (504 families) and association (940 families): p values, 0.0001 and 0.0014 at D2S2214, respectively, and 0.0008 and 0.0006 at D2S116, respectively. These findings suggest that variation in the CD28/CTLA4 gene region is a determinant of coeliac disease susceptibility. Dissecting the sequence variation underlying this relationship will depend on further analyses utilising denser sets of markers.

Factors associated with tolerance to, and discomfort with, unsedated diagnostic gastroscopy

BACKGROUND

Identification of patients likely to experience high levels of discomfort during unsedated gastroscopy would be useful as these patients could be prospectively targeted for sedation. We prospectively assessed patient and endoscopic variables in subjects attending for endoscopy in order to identify factors associated with patients' experience of the unsedated examination.

METHODS

We studied 508 patients attending for routine diagnostic gastroscopy. Clinical and endoscopic data were collected and patients completed a two-part questionnaire assessing their anxiety with, and experience of, the procedure.

RESULTS

Thirty-nine subjects failed to complete the initial unsedated endoscopy. Failure to tolerate endoscopy was associated with younger age (P = 0.002) and examination with a standard-bore (> or = 9.0 mm) endoscope (P = 0.004). High levels of patient discomfort during the procedure were associated with younger age (P < 0.001), high levels of pre-endoscopic anxiety (P < 0.001), high levels of pre-endoscopic discomfort due to throat spray (P = 0.02) and examination with a standard-bore endoscope (P < 0.001). Preference for sedation during future examinations was related to female gender (P = 0.02), young age (P = 0.02), high levels of apprehension (P < 0.001), the examining doctor (P = 0.002) and use of a standard-bore endoscope (P < 0.001).

CONCLUSIONS

Discrete clinical characteristics and endoscopic variables are associated with patients' experience of unsedated endoscopy. Further work might result in an algorithm for identifying patients who would benefit from sedation prior to gastroscopy.

Pulse oximetry saturation levels during routine unsedated diagnostic upper gastrointestinal endoscopy

BACKGROUND

Diagnostic procedures account for over 90% of all upper gastrointestinal endoscopies. Pulse oximetry saturation (SpO2) levels were assessed in patients attending for routine unsedated diagnostic gastroscopy to identify factors associated with oxygen desaturation.

METHODS

Three hundred and thirty unsedated patients were monitored with continuous pulse oximetry. A further 154 patients who requested sedation prior to endoscopy were studied as a positive control group.

RESULTS

SpO2 levels were lower in sedated compared to unsedated patients (P < 0.0001). Six unsedated patients (2%) desaturated to 90% or less during endoscopy compared to 32 sedated patients (21%) (P < 0.0001). SpO2 levels in unsedated patients were not related to patient sex, age, cigarette smoking, endoscope diameter, basal SpO2 levels or duration of endoscopy. In contrast, examination of the pharyngeal area and epiglottis (P = 0.0002) and a longer intubation time (P = 0.0002) were associated with lower SpO2 levels. The lowest SpO2 level recorded during unsedated endoscopy was 88%.

CONCLUSION

Pulse oximetry is not a prerequisite to performing routine unsedated diagnostic gastroscopy in patients without severe systemic disease.

The incidence of joint involvement with adjacent osteomyelitis in pediatric patients

Sixty-six patients admitted to our institution over an 8-year period with the diagnosis of osteomyelitis were analyzed to determine the incidence of adjacent joint involvement. Patients with osteomyelitis of the hand, foot, spine, and extraarticular pelvis were excluded from this study. The average age was 5.8 years (range, 1 month to 17 years). Forty-two percent of our patients who had osteomyelitis had evidence of adjacent joint involvement (either septic or nonseptic). One third of our patients had evidence of septic joint involvement. The most commonly involved joint was the knee. There was no difference in the incidence of adjacent joint involvement in those patients who were younger than 18 months compared with the incidence in older children. Our study suggests that the incidence of adjacent joint involvement in children who have osteomyelitis is higher than that suggested in the literature. We believe that careful evaluation of the adjacent joint should be an important part of the evaluation of any child who has osteomyelitis.

Estimation of defect volume in segmental defects of the tibia and femur

BACKGROUND

With the advent of modern limb salvage techniques, segmental bone loss in the lower extremity has become more common.

METHODS

To aid preoperative planning when dealing with segmental bone loss in the femur and tibia, we performed a cadaveric study to estimate the volume of autogenous or allograft material required to fill defects located in various areas of the bones.

RESULTS

The greatest volume was generally required in metaphyseal defects, with an average of 12 cc/cm in the distal femur and proximal tibia, 11 cc/cm in the proximal femur, and 6 cc/cm in the distal tibia. Diaphyseal defects were found to have the least variability with regard to the volume of graft material required for different specimens. Femoral diaphyseal defects required 7 cc/cm and tibial diaphyseal defects required 5 cc/cm. A slightly larger volume of allograft material was needed to fill all defects compared with autograft.

CONCLUSION

This method allows one to estimate the amount of graft required for a defect of the femur and the tibia.

Does CagA contribute to ulcer pathogenesis in a developing country, such as Sudan?

BACKGROUND AND OBJECTIVE

In Western populations, peptic ulcer disease is closely associated with Helicobacter pylori (H. pylori) strains expressing the CagA antigen. In Africa the prevalence of H. pylori infection and peptic ulcer disease is high, although information regarding potential virulence factors is lacking. This study examines the prevalence of antibodies to CagA both in African patients with dyspepsia who are undergoing gastroscopy, and in asymptomatic healthy African volunteers.

METHODS

Eighty two consecutive patients (median age 34 years, range 15-73 years), attending for gastroscopy were studied, of whom 78 (95.1%) were subsequently found to be Helicobacter positive. Three antral biopsies were obtained from each patient and 5 ml of blood was taken for determination of CagA seropositivity using western blot analysis. CagA seropositivity was also determined in 65 H. pylori positive healthy volunteers (median age 30 years, range 18-70 years), with no symptoms or previous history of gastroduodenal disease.

RESULTS

Of the 78 H. pylori positive patients, CagA seropositivity was present in all 22 patients with active peptic ulcer disease (100%), in eight of nine patients with duodenitis (89%), in 15 of 19 patients with macroscopic gastritis (78.9%), and in 24 of 28 patients with a normal endoscopy (85.7%). On histological assessment, 46 patients had chronic active gastritis, 29 patients had gastritis with atrophy and three patients had intestinal metaplasia. CagA seropositivity rates were 84.7%, 93% and 100%, respectively, for these groups. In the 89 healthy volunteers studied, 57 of the 65 H. pylori positive subjects (87.7%) were seropositive for the CagA protein.

CONCLUSIONS

As in Western countries, CagA seropositivity in this African population was closely related to endoscopic gastroduodenal disease, and to the presence of more advanced histological lesions in the antrum. However, there was also a high prevalence of CagA seropositivity in asymptomatic healthy individuals, suggesting that factors other than CagA predominate in ulcer pathogenesis in this population.

Effect of partial versus complete plantar fasciotomy on the windlass mechanism

Eight adult below-knee cadaver specimens were placed in a testing machine and loaded to 350 newtons according to a strict protocol. Arch height and length measurements were obtained in each specimen with the toes resting on the foot plate, dorsiflexed to 30 degrees, and maximally dorsiflexed manually. The plantar fascia was then divided from medial to lateral in one-quarter increments, and the effect on arch height and length measurements was assessed using the same loading protocol. A consistent decrease in the arch-supporting function on sequential sectioning of the plantar fascia was encountered. A less consistent decrease in the arch-supporting function was reflected by the increase in the height of the arch with sequential sectioning of the plantar fascia. The study demonstrates that partial plantar fasciotomy decreases the arch-supporting function of the plantar fascia in addition to weakening the structure. Strict surgical indications for this type of procedure should be maintained.

Rehabilitation after total knee arthroplasty: a comparison of 2 rehabilitation techniques

This study was conducted to compare postoperative total knee arthroplasty rehabilitation protocols. The hypothesis of this study was that patients undergoing total knee arthroplasty could achieve range of motion and hospital discharge in the same period using a postoperative rehabilitation protocol that did not use a continuous passive motion machine. This randomized prospective study compared 46 total knee arthroplasties in which a continuous passive motion machine was used with 37 total knees that were rehabilitated with early passive flexion of the knee (named drop and dangle protocol). Postoperative physical therapy regimens were otherwise the same for both groups. Surgical technique was the same for both groups except for closure which was performed in the drop and dangle group with the knee at 90 degrees to 95 degrees flexion. Only patients with osteoarthritis were included in the study, and in both groups of patients received the same prosthetic components. Patients in the drop and dangle group were discharged from the hospital 1 day earlier (p = 0.01) and had a statistically better extension range of 2.8 degrees at 6 months (p = 0.03). Knees in the drop and dangle group had less drainage (p = 0.06). Range of motion and hospital discharge can be achieved in a similar time interval with the drop and dangle technique as with using a continuous passive motion device, and that such a device is not required for postoperative knee rehabilitation.

Misoprostol in the prevention of gastroduodenal damage in rheumatology

Patients receiving non-steroidal anti-inflammatory drugs (NSAIDs) are at an increased risk of gastroduodenal erosions, ulcers, and the associated complications of haemorrhage, perforation, and death. Many NSAID associated ulcers that bleed or perforate have been asymptomatic until the time of presentation and conversely many patients with dyspepsia do not have ulcers. Symptoms are a poor guide to the presence of an ulcer. During continued treatment with NSAIDs misoprostol is the best choice for NSAID induced gastroduodenal damage; it achieves higher rates of healing than other drugs in these circumstances. Misoprostol is superior to other drugs in the prevention of gastric damage but misoprostol and H2 antagonists are of similar benefit in the duodenum. Prophylactic studies have all used endoscopic damage as an endpoint, and much larger studies will be needed to show an effect of misoprostol on the incidence of ulcer complications. There are no clear guidelines as to which patients should receive prophylactic treatment with misoprostol but those particularly at risk of ulcer complications--that is, those with previous peptic ulceration, the elderly, medically unfit, patients receiving large doses of NSAIDs, and those patients receiving steroids in addition to NSAIDs--should be considered.

Case report: tuberculous colitis mimicking Crohn's disease

Although intestinal tuberculosis is rare in this country, increasing numbers of patients are now being seen, particularly in the immigrant population. We present the history of a lady who had acute diarrhoea and in whom the radiological and endoscopic findings looked very similar to those seen in Crohn's disease. The radiological presentation included widespread aphthous ulceration, a feature that has rarely been reported in tuberculous colitis.

Duodenal varices. A neglected cause of massive, recurrent gastrointestinal bleeding

Bleeding from duodenal varices in portal hypertension may not be recognized, resulting in a delay in diagnosis. Early detection is important as duodenal varices are a potential source of massive hemorrhage. We report two cases with recurrent upper gastrointestinal hemorrhage in whom accurate diagnosis was made only after extensive investigation including repeated endoscopic examination.

Low gluten diet in the treatment of adult coeliac disease: effect on jejunal morphology and serum anti-gluten antibodies

Treatment of patients with coeliac disease with a low gluten containing diet (LGD) remains controversial. We have studied jejunal morphology and antigluten (AG) antibody titres by ELISA in patients on a LGD of 2.5-5 g/day for three to 14 months (median six months) and compared results with patients on a strict gluten free diet (GFD) for six to 27 months (median 13 months). We found no significant difference in villous height or crypt depth (eight LGD v 10 GFD patients) or serum AG-IgA, -IgG, and IgM titres (13 LGD v 12 GFD patients). there was however, a significant increase (p less than 0.05) in intra-epithelial lymphocytes in those patients on a LGD. We conclude that adult coeliac patients can tolerate a LGD without gross morphological change and without initiating significant AG antibody responses.

The teenage coeliac: follow up study of 102 patients

Over a 10 year period a total of 102 teenage patients with coeliac disease were assessed on transfer from paediatric hospitals to an adult clinic. Fifty seven patients said they were on a strict gluten free diet; 36 were semistrict, and nine admitted to eating a normal diet. Jejunal mucosal abnormalities, however, suggested that many patients on the 'strict' diet were actually consuming gluten. All patients were well with biochemical parameters within the normal range. Height percentiles were not significantly different from the normal population but patients, as a group, were significantly lighter.

Evidence for the role of a human intestinal adenovirus in the pathogenesis of coeliac disease

We previously noted a region of amino acid sequence homology between A-gliadin, a major alpha-gliadin component known to activate coeliac disease, and the early region E1b protein of human adenovirus serotype 12 (Ad12), an adenovirus isolated from the human intestinal tract. In the present study sera from coeliac disease patients from the United Kingdom and the United States were assayed for neutralising antibody to Ad12 as evidence of past exposure to that virus and for antibody to synthetic peptides of A-gliadin from the region of shared sequence with the Ad12 E1b protein. Eighty nine per cent of untreated coeliac disease patients had evidence of previous Ad12 infection. There was also a significant increase in the prevalence of neutralising antibody to Ad12 among treated adults (33.3%) and children (30.8%) with coeliac disease compared with controls (0-12.8%) in the western USA and in London. There was no evidence for an increased prevalence of infection with a closely related adenovirus, adenovirus 18, or another enteric virus, Echovirus 11, among coeliac disease subjects. Additional studies documented that a region of A-gliadin that shares amino acid sequence homology with the adenovirus 12 E1b protein could be recognised as an antigenic determinant in active coeliac disease patients. Taken together, these data are compatible with the hypothesis that a viral protein may play a role in the pathogenesis of coeliac disease, perhaps by virtue of immunological cross reactivity between antigenic determinants shared by the viral protein and alpha-gliadins.

Gliadin binding to rat and human enterocytes

Binding of 125I-crude gluten digest (Frazer's fraction III. FF-III) and 125I-concanavalin A (Con A) to isolated rat enterocytes and of 125I-FF-III to human enterocytes was investigated. Specific binding of 125I-FF-III to rat enterocytes was observed but binding was not inhibited by any of a range of simple and complex saccharides. although casein and bovine serum albumin displaced FF-III at high concentrations. Con A also bound to enterocytes in a specific manner and was inhibited by alpha-methyl-D-mannoside, confirming a lectin-mediated interaction. 125I-FF-III exhibited quantitatively similar specific binding to both normal human and coeliac enterocytes. The primary interaction of gliadin peptides with the enterocyte surface membrane is not lectin-mediated and unlikely to be of fundamental importance in the pathogenesis of coeliac disease.

Reappraisal of the 'lectin hypothesis' in the aetiopathogenesis of coeliac disease

The agglutinating properties of a crude gluten digest, purified gliadin fractions and established plant lectins were investigated using mammalian erythrocytes, rat enterocytes and normal and coeliac human enterocytes as the target systems. Gliadin preparations failed to cause agglutination of any of the cells tested, whereas established pure plant lectins were active cell agglutinins. These studies indicate that gliadin peptides do not interact with intestinal cells in a polyvalent, lectin-like manner and as such cannot be regarded as true lectins. Mucosal damage in coeliac disease is unlikely therefore to be related to lectin-like activity of gliadin.

The microvillus in adult jejunal mucosa--an electron microscopic study

The increase in surface area contributed by microvilli per square unit mucosal surface area in the jejunal villus, i.e. amplification factor, has been studied in four normal adults and three adults with treated coeliac disease. Villi were split into three regions, photomicrographs of microvilli were taken from each region and the microvillus amplification factor calculated. The mid-villus region contributed a significantly greater microvillus amplification factor than either the low or upper regions in all patients studied. In addition surface cell heights were greatest in the low- and mid-villus regions. This suggests that the enterocytes in the mid-villus region are best adapted for absorption, and that the enterocytes in the upper-villus regions are undergoing an ageing process.

Treatment of advanced malignant melanoma with high-dose melphalan and autologous bone marrow transplantation

Twenty-eight patients with advanced life-threatening metastatic malignant melanoma were treated with high dose (140-260 mgm-2) intravenous melphalan and autologous bone marrow. Cyclophosphamide "priming" 300 mgm-2 i.v. was given to 19 patients one week previously and this resulted in clinical but not histological evidence of amelioration of gastrointestinal toxicity. In 11 patients (43%) there was evidence of tumour response to treatment and in 2 patients complete remissions were observed. However in most patients, responses were short-lived and no patient lived longer than 17 months from start of treatment or 24 months from first recorded evidence of distant metastatic disease.

Radiologic features of the jejunum in hypoalbuminemia

Although hypoalbuminemia is a recognized cause of jejunal dilatation, the level of serum albumin at which this occurs and its relation to the extent of jejunal dilatation in celiac disease have not been clearly established. Barium follow-through examination was performed in 12 patients with hypoalbuminemia, in 21 patients with celiac disease, some of whom had a reduced serum albumin, and in 14 control subjects. Jejunal width was increased in patients with hypoalbuminemia and there was a highly significant correlation between jejunal width and the level of serum albumin (p less than 0.001). The level of serum albumin at which jejunal dilatation occurred ("albumin threshold") was found to be 27 g/l. Hypoalbuminemia was not found to be an important factor in the jenunal dilatation of celiac disease. There was a close correlation between the presence of edema and ascites and radiologic abnormality in the jejunum, suggesting that these appearances in nephrotic syndrome are due to intestinal edema. This study suggests that the serum albumin should be taken into account when interpreting the caliber of the small intestine.

The existence of inflammatory bowel lesions in gluten-sensitive enteropathy

Three patients with coincident coeliac disease and inflammatory bowel disease are described. In 2 patients with known coeliac disease the recurrence of diarrhoea was not due to dietary deviation but to an additional large bowel pathology.

Reintroduction of gluten in adults and children with treated coeliac disease

Twenty-eight patients, thought to have coeliac disease and on gluten free diets, were put on a normal diet to confirm their diagnoses. Nineteen had been diagnosed in adult life (ACD) and nine in childhood (CCD). Patients were assessed on jejunal, morphological, and symptomatic parameters. Eighteen patients with ACD relapsed within seven weeks. Nine patients with CCD relapsed at variable times but five took longer than seven weeks, the longest period beint 10 months. Seven patients had no symptoms despite morphological deterioration during challenge and one patient, with ACD, did not relapse and was HLA B8 negative. This patient with ACD had subtotal villous atrophy on two jejunal biopsies and later showed morphological improvement on a gluten free diet. There was no correlation between the relapse time and time spent on a gluten free diet.

Immunological phenomena in the jejunum and serum after reintroduction of dietary gluten in children with treated coeliac disease

Jejunal mucosal immunoglobulin-containing cells of all three major classes (IgA, IgM, IgG) were increased in coeliac children on gluten-containing diets but only IgM cell numbers were raised in those on gluten-free diets. Patients with subtotal villous atrophy had greater numbers of immunoglobulin-containing cells than patients with normal mucosa. In previously treated patients studied before and after three months on a gluten-containing diet ther was an increase in all three classes of cell, IgM containing cells showing the greatest proportional rise. Basement membrane staining with anti-IgA serum occurred in coeliacs and was most intense in untreated patients. Apart from one patient with very low levels of serum IgA, serum immunoglobulins did not differ from normal. However, after reintroduction of gluten to the diet a significant fall in serum IgM concentrations occurred compared with levels in the same patients while on gluten-free diets. It seems probable that both IgA and IgM systems are important in the immunopathogenesis of the small intestinal lesion of childhood coeliac disease.

Cellular infiltrate of the jejunum after re-introduction of dietary gluten in children with treated coeliac disease

Jejunal lamina propria plasma cells and eosinophils and intraepithelial lymphocytes were raised in coeliac children on gluten-containing diets, but only intraepithelial lymphocytes were increased in patients on gluten-free diets. In contrast, lamina propria lymphocytes were reduced in children with coeliad disease on gluten-containing diets but were normal in paitents on gluten-free diets. In children with coeliac disease who were studied serially, lamina propria plasma cells and eosinophils and intraepithelial lymphocytes increased, and lamina propria lymphocytes decreased, within three months of the reintroduction of gluten to the diet. These observations are essentially similar to those made in the adult form of the disease and suggest that more than one type of immunological reaction is involved in the pathogenesis of the jejunal lesion.

T cell depletion in untreated adult coeliac disease

The proportional and absolute numbers of circulating thymus dependent lymphocytes (T cells) were reduced in untreated patients with coeliac disease but were normal after treatment with a gluten free diet. There was an inverse correlation between circulating T cell numbers and jejunal intraepithelial lymphocytes. This evidence suggests a possible role for T cells in the pathogenesis of coeliac disease and is a further example of disturbed cell mediated immunity in this condition.

Gastric lesion in dermatitis herpetiformis

Five of 33 patients with dermatitis herpetiformis (DH) were found to have gastric parietal cell antibody in their sera, whereas it was not found in 30 healthy controls of comparable age distribution. Fifteen of the patients with DH underwent further studies to investigate the histological and functional state of their gastric mucosa. Atrophic gastritis was found in all five patients whose sera contained gastric parietal cell antibody and in three of 11 patients with no antibody in their sera. In addition, there was marked impairment of acid secretion in the DH group as a whole, but, apart from one patient with overt pernicious anaemia (PA), there was no evidence of malabsorption of B12.

Food antibodies in patients with dermatitis herpetiformis and adult coeliac disease - relationship to jejunal morphology

Serum antibodies to a variety of dietary proteins were investigated in 26 patients with adult coeliac disease (ACD, 14 untreated and 17 treated with a gluten-free diet) and 38 patients with dermatitis herpetiformis (DH) with varying small bowel abnormalities. The incidence of one or more positive tests was highest in untreated ACD (73.4%) and DH with subtotal villous atrophy (57.4%). This incidence fell with morphological improvement, being 56.4% in treated ACD patients with partial villous atrophy (PVA), and 33.4% in DH with PVA, and 0% in DH with normal biopsies. The height of the serum antibody titre also fell with morphological improvement. These results show that there is an abnormally high incidence of dietary antibodies in patients with DH, and this correlates with the degree of small bowel damage.

The cellular infiltrate of the jejunum in adult coeliac disease and dermatitis herpetiformis following the reintroduction of dietary gluten

The cellular infiltrate of the jejunal mucosa has been studied in patients with both treated and untreated adult coeliac disease and dermatitis herpetiformis and serially in treated patients before and after the reintroduction of gluten to the diet. In adult coeliac disease and dermatitis herpetiformis the jejunal mucosa showed similar abnormalities of the cellular infiltrate which was characterized by an increase in intraepithelial lymphocytes and lamina propria plasma cells and eosinophils, with the greatest numbers of cells occurring in untreated patients. At 24-48 hours following a single 25-g gluten challenge there was an increase in lamina propria plasma cells, lymphocytes and eosinophils and intraepithelial lymphocytes. This rise was sustained after seven days on a gluten-containing diet for all of these cell groups except lamina propria lymphocytes. These responses were essentially similar in both adult coeliac disease and in those dermatitis herpetiformis patients who had jejunal lesions before treatment. In dermatitis herpetiformis patients with normal jejunal morphology on a normal diet there was an upward trend in lamina propria plasma cells and intraepithelial lymphocytes within one to three weeks of taking extra dietary gluten. These results are compatible with the view that more than one immunological mechanism may be responsible for the pathogenesis of the jejunal lesion of coeliac disease and dermatitis herpetiformis.

Ileal function in patients with untreated adult coeliac disease

A double-lumen perfusion technique has been used to investigate jejunal and ileal absorption of glucose, water, and electrolytes in a group of patients with untreated adult coeliac disease. Correct positioning of the tube was confirmed by measuring the differential jejunal and ileal handling of bicarbonate. Eight control subjects and eight patients with coeliac disease were perfused with an isotonic electrolyte solution containing 50 mM glucose and 25 mM bicarbonate. The group of coeliac patients had impaired jejunal absorption of glucose (P less than 0.001), water (P less than 0.01), sodium (P less than 0.02), and chloride (P greater than 0.05) compared with the control group. In contrast the group of coeliac patients had normal ileal glucose and water absorption and increased ileal sodium (P greater than 0.01) and chloride (P greater than 0.05) absorption compared with the controls. Evidence for ileal adaptation was found in three individual patients who had absorptive values outside 2SD of the normal mean. The results indicate that the distal small intestine in coeliac disease has the ability to adopt to the damage and loss of absorptive capacity in the proximal small intestine.

Amino acid and peptide absorption in patients with coeliac disease and dermatitis herpetiformis

A double-lumen perfusion technique has been used to study amino acid and peptide absorption in eight normal control subjects, 13 patients with untreated adult coeliac disease, and 16 patients with dermatitis herpetiformis who had varying morphological abnormalities of the small bowel. All subjects were perfused with isotonic solutions containing 10 mM glycyl-L-alanine and 10 mM glycine + 10 mM L-alanine. Patients with adult coeliac disease had impaired absorption of glycine (p < 0.01) and L-alanine (p < 0.05) from the amino acid solution compared with the control subjects. Amino acid uptake from the dipeptide solution was not significantly impaired, although four individual patients had impaired uptake of both amino acids. In contrast to these findings, very few patients with dermatitis herpetiformis had impaired amino acid absorption from either solution. Sodium absorption was impaired from both solutions when the groups of patients with adult coeliac disease and dermatitis herpetiformis with subtotal villous atrophy and partial villous atrophy were studied, and there were patients in each group who secreted sodium and water. The results suggest that malabsorption of dietary protein is unlikely to occur in dermatitis herpetiformis but may occur and contribute to protein deficiency seen in some severe cases of adult coeliac disease. The impairment of sodium and water absorption provides evidence that there may be functional impairment of the jejunal mucosa in dermatitis herpetiformis as well as in adult coeliac disease.

Is the xylose test still a worth-while investigation?

In a retrospective survey the results of a D-xylose absorption test have been assessed in relation to jejunal morphology and final diagnosis in 152 adult patients with various types of gastrointestinal disease. Neither urine excretion rates nor serum concentrations alone provide an adequate separation between patients with definite mucosal lesions and those without evidence of gut disease or with other types of gastrointestinal pathology.It is suggested that when a jejunal biopsy can readily be performed the xylose test serves little useful purpose in routine practice and can be positively misleading. It may still be useful as a screening test for referral for jejunal biopsy, provided that strict criteria of normality are applied.