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Toxin-positive strains of Staphylococcus aureus (T + S. aureus) are present on the skin of some but not all patients with atopic dermatitis. Many staphylococcal toxins are superantigens, which can stimulate the immune response and thus may potentially lead to the very high levels of IgE characteristic of this condition, as well as exacerbating the clinical disease. The aim of this study was to determine whether the presence of T + S. aureus on the skin of children with atopic dermatitis was associated with in vivo evidence of a heightened humoral immune response, higher IgE levels and more severe clinical disease. Toxin gene expression in S. aureus isolated from the eczematous lesions of 28 children with atopic dermatitis was assessed by PCR. Clinical and immune data were also collected from this cohort. Thirteen of the 28 children (46%) were colonized with T + S. aureus strains. The presence of T + S. aureus was associated with a significant expansion in peripheral blood CD5- B cells (P = 0·01), and the more toxin types identified the greater the B-cell expansion (P = 0·002). However, in this cohort of children with atopic dermatitis, despite th in vivo expansion of B cells in children harbouring T + S. aureus, there was no associated increase in IgE levels or in clinical disease severity scores. [ABSTRACT FROM AUTHOR]

Quality standards have been established in two key areas of pathology directly relevant to standards for the provision of emergency medical services. First, there is a national scheme for accreditation of laboratory services--Clinical Pathology Accreditation (UK) Ltd (CPA)--which has been in formal operation since 1992 and currently covers about 80% of all UK laboratories. Secondly, guidelines have been issued by the Joint Working Group on Quality Assurance (JWGQA) on the support to any point-of-care (near patient) testing facilities. Point-of-care testing (POCT) is increasingly popular in emergency areas, where the availability of faster test results is expected to expedite diagnosis and treatment. When laboratory services are not accredited or POCT equipment and its usage are outside laboratory supervision, there should be concerns that quality standards for pathology service support of the emergency services are not being met. [ABSTRACT FROM AUTHOR]

The development of safe and effective intravenous preparations of immune globulin (IVIG) represents a major advance in the treatment of patients with severe antibody deficiencies. Such therapy is expensive, few trials have been performed to compare one type of IVIG preparation with another under equivalent conditions, and published studies have been of relatively short duration. The overall consensus is that high-dose IVIG (at least 400/mg/kg/month) is superior to lower doses and most clinicians aim to maintain trough IgG levels above an arbitrary level of 5 g/l. Adverse reactions, usually mild, are common in antibody-deficient patients during the first few infusions, but severe, anaphylactoid reactions are extremely rare other than in patients with antibodies to IgA. IVIG is not associated with transmission of human immunodeficiency virus or hepatitis B. but there remains a small but definite risk of transmission of non-A, non-B hepatitis, including hepatitis C. Self-infusion of IVIG in the patients home is a realistic alternative to hospitalization. In the UK, guidelines for home therapy have been approved by professional medical bodies and by the Department of Health. Home therapy has proven to be both safe and cost-effective. [ABSTRACT FROM AUTHOR]

A 75 year old maturity-onset diabetic developed persistent local allergy to insulin. She had coexistent asymptomatic chronic lymphatic leukaemia. All species of insulin provoked a recurrence of the allergy and attempts at hyposensitization and treatment of the leukaemia produced only marginal benefit. Administration of subcutaneous steroids with insulin relieved the problem, but could not be stopped without relapse. Immunological investigations suggested an immune complex-mediated hypersensitivity reaction to insulin. The later development of immune complex-mediated arthropathy tended to support this suggestion. The lack of histological and immunological evidence of an IgE-mediated reaction suggested that in this case the mechanism of insulin allergy and arthralgia was IgG mediated. We suggest that the chronic leukaemia was implicated in both processes by interfering with homeostatic mechanisms that normally prevent the development of autoallergic disorders. [ABSTRACT FROM PUBLISHER]

A case of Whipple's disease in a female is described. Malabsorption of iron, vitamin B12, folic acid and fat was present. These abnormalities reverted to normal after introduction of co-trimoxazole therapy. The patient's humoral immune system was normal, in contrast to impairment of cell-mediated immunity, which has not improved in spite of co-trimoxazole treatment for 2 years, and a therapeutic trial of levamisole. These findings are further evidence that there may be a primary immune deficiency in patients with Whipple's disease. [ABSTRACT FROM PUBLISHER]

A case of eosinophilic gastroenteritis in a 42-year-old man is described. The patient had diarrhoea, faecal blood loss, a protein-losing enteropathy, malabsorption of fat, xylose and vitamin B12. Co-existent hypopituitarism, diabetes insipidus and hypothalamic dysfunction was demonstrated. Complete clinical recovery occurred with pituitary replacement therapy alone. The association of this endocrine abnormality with the picture of eosinophilic gastroenteritis has not previously been described. [ABSTRACT FROM PUBLISHER]

Using a flow cytometric method, CD4+, CD8+, αβ TCR+ and TCR variable region gene product (TVRGP)-specific T cells were analysed in healthy heterosexual males (HHeM), HIV-seronegative homosexual males (SNHM). asymptomatic seropositive homosexual males (ASPH) and homosexual males with AIDS who were either well (AIDS-A). or unwell in hospital (AIDS-B), Total CD4+ and CD8+ T cell numbers were similar in HHeM and SNHM. CD4+ T cells were significantly reduced in ASPH relative to both HHeM and SNHM and in AIDS-A and AIDS-B relative to SNHM, TVRGP specific T cells expressed as a percentage of TCR αβ+ cells showed no significant difference in HHeM, SNHM and AIDS-B. The proportion of αβ+ cells expressing the Vβ5.1, Vβ12 and Vα2 gene product (GP) was. however, significantly reduced in ASPH and AIDS-B relative to HHeM. SNHM and AIDS-A. Possible causes of TVRGP-specific T cell deletion are discussed. [ABSTRACT FROM AUTHOR]

Faecal alpha-1-antitrypsin and 51Cr-albumin losses in 42 patients with either gastrointestinal or hepatic disease were compared. The reference range was derived from measurements in 20 controls without gastrointestinal disease. Alpha-1-antitrypsin excretion was increased in patients with excessive 51Cr-albumin loss, and correlations were found between alpha-1-antitrypsin clearance and 51Cr-albumin excretion. Because of the considerable overlap of faecal alpha-1-antitrypsin excretion between controls and patients, sensitivity and specificity of the test were only 58% and 80%, respectively. This poor reliability could not be explained by sampling error or temporal variations in alpha-1-antitrypsin excretion. These results show that although faecal alpha-1-antitrypsin excretion correlates with 51Cr-albumin excretion when whole groups of patients are studied, its poor sensitivity makes it an unreliable measure of enteric protein loss. [ABSTRACT FROM PUBLISHER]

Several diseases of the small intestine, including gluten-sensitivity, present with malabsorption and a "flat" mucosa. Determination of the mitotic index of epithelial lymphocytes provides a simple, objective method of assessing, and thus of predicting, whether a flat mucosa is due to gluten-sensitivity (index greater than 0.2%), or not (index less than 0.2%). The use of this index in circumstances especially likely to cause diagnostic confusion--for example, intestinal lymphoma; Crohn's jejunitis of immunodeficiency--is illustrated in this paper. Of seven cases, five (two primary lymphoma, three immunodeficiency) had been treated with a gluten-free diet without benefit; a mitotic index performed on the initial biopsy in each of these patients could have predicted from the outset that none was gluten-sensitive. Of the remaining two cases, determination of the mitotic index on the biopsy initially obtained from a man with severe hypogammaglobulinaemia would have indicated that he was also gluten-sensitive. Empirical use of a gluten-free diet was avoided in the other patient (with flat small intestinal mucosa and low mitotic index) in whom the diagnosis was ultimately shown to be due to Crohn's disease of jejunum. [ABSTRACT FROM PUBLISHER]

Circulating antibodies to soya-derived protein antigens have been measured in patients with duodenitis, Crohn's disease, ulcerative colitis and coeliac disease. Significantly raised antibody titres were found frequently in the coeliac group, particularly those patients showing a suboptimal response to a gluten-free diet, but rarely in subjects with other gastrointestinal diseases. Antisoya activity was not necessarily accompanied by antibodies to other common dietary antigens. We suggest that some coeliacs may have an associated dietary soya sensitivity which could adversely influence their response to gluten withdrawal. [ABSTRACT FROM PUBLISHER]

The technique of immunoelectrophoresis (IEP) is widely employed in the qualitative analysis of serum immunoglobulins. The most commonly used support media are agarose or agar gels, but the mobility of immunoglobulins is different in these two media. The presence of a small amount of a cathodal monoclonal immunoglobulin G may not be detected on IEP in agar if it is masked by larger amounts of polyclonal immunoglobulin of the same class. In these circumstances the use of agarose imparts to the monoclonal protein a different mobility from that of the bulk of the serum IgG and allows its positive identification. [ABSTRACT FROM PUBLISHER]