Appropriate clinical use of human leukocyte antigen typing for coeliac disease: an Australasian perspective.

The past decade has seen human leukocyte antigen (HLA) typing emerge as a remarkably popular test for the diagnostic work-up of coeliac disease with high patient acceptance. Although limited in its positive predictive value for coeliac disease, the strong disease association with specific HLA genes imparts exceptional negative predictive value to HLA typing, enabling a negative result to exclude coeliac disease confidently. In response to mounting evidence that the clinical use and interpretation of HLA typing often deviates from best practice, this article outlines an evidence-based approach to guide clinically appropriate use of HLA typing, and establishes a reporting template for pathology providers to improve communication of results.

Consensus guidelines on anti-beta 2 glycoprotein I testing and reporting.

Consensus guidelines on anti-beta 2 glycoprotein I (anti-beta2GPI) testing have been developed to help minimise laboratory variation in the performance and reporting of assays for these antibodies. These guidelines include minimum and optional recommendations for the following aspects of anti-beta2GPI testing and reporting: (1) isotype of anti-beta2GPI tested; (2) specimen type; (3) controls and assay precision; (4) calibrators; (5) patient samples; (6) rheumatoid factors and IgM anti-beta2GPI testing; (7) reporting of results; (8) cutoff values; and (9) interpretative comments. Issues related to inter-kit/assay standardisation and the manufacturing process of commercial anti-beta2GPI kits/assays have not been addressed in the current guidelines.

Severe intimal hyperplasia with ischaemic colitis in two patients with hepatitis C.

Many extrahepatic manifestations of hepatitis C have been described, including renal disease and vasculitis. We describe the novel finding of intimal hyperplasia associated with severe ischaemic events in two patients with hepatitis C. The combination of genotype 1a hepatitis C virus, rapidly progressive mesangiocapillary glomerulonephritis and intimal hyperplasia with ischaemic sequelae, may represent a new syndrome.

Lipoprotein interaction with artery wall derived proteoglycan: comparisons between atherosclerosis-susceptible WC-2 and resistant Show Racer pigeons.

The binding of intact, high molecular weight, aortic proteoglycan (PG) isolated from grossly normal appearing aortas of atherosclerosis-susceptible White Carneau pigeons (WC-2) and -resistant Show Racer pigeons (SR) to homologous and heterologous serum lipoproteins from both normolipemic and hyperlipemic pigeons was examined. In vitro binding studies were done using a mixture of purified chondroitin sulfate PG and dermatan sulfate PG monomers to simulate an in situ composition. For each animal, a binding potential or reactivity number was calculated and corresponded to the shape and slope of the PG-LDL binding curve, where higher values indicated greater reactivity. For WC-2 normal sera, mean values were 0.97 and 0.95 using WC-2 and SR PG respectively, compared to SR normal sera (equivalent total plasma cholesterol) where values were 0.80 and 0.82. Corresponding mean reactivity values for hyperlipemic sera (diluted to a cholesterol concentration of 300 mg/dl) were 0.95, 1.00, 0.73, and 0.79. The results suggest that LDL from both normolipemic and hyperlipemic atherosclerosis-susceptible WC-2 pigeons is more reactive in complexing to artery wall derived PG than LDL from SR pigeons, regardless of PG source.

Artery wall derived proteoglycan-plasma lipoprotein interaction: lipoprotein binding properties of extracted proteoglycans.

Artery proteoglycan-lipoprotein binding characteristics were determined using intact, high molecular weight chondroitin sulfate proteoglycans (CS-PG) isolated from grossly appearing normal aortas of atherosclerosis susceptible WC-2 pigeons and plasma lipoproteins from normolipemic, randomly bred White Carneau pigeons. Optimum formation of particulate proteoglycan-lipoprotein complexes occurred in 5 mM Tris, 6 mM KCl, 4 mM CaCl2, 1 mM MgSO4, pH 7.2. The binding of CS-PG was specific for low density lipoprotein (LDL) and not high density lipoprotein (HDL). The relative importance of the intact monomeric structure of the PG was suggested in studies where glycosaminoglycan chains isolated from the PG monomer possessed less than 1% of the binding reactivity of the intact PG. The core protein prepared from the CS-PG monomer formed no measurable particulate complex.

A comparison of 13 guinea pig and human anti-tissue transglutaminase antibody ELISA kits.

AIMS: Tissue transglutaminase (tTG) is a major autoantigen recognised by IgA anti-endomysial antibodies (IgA EMA). Enzyme linked immunosorbent assays (ELISA) for IgA anti-tissue transglutaminase antibodies (IgA tTG) have therefore been developed as an alternative serological screening test to IgA EMA for coeliac disease (CD). The use of human tTG (h-tTG), as opposed to guinea pig liver tTG (gpl-tTG), in these assays has been reported to produce superior results. This study compared 13 commercial IgA tTG ELISA kits to ascertain their performance characteristics in the diagnosis of CD in patients with biopsy confirmed disease compared with controls. All patients and controls were adults aged 21 years or older. METHODS: Sera from the following groups of patients were tested in each kit: (1) 49 patients with CD confirmed on small bowel biopsies (all IgA EMA positive); (2) 34 patients with small bowel biopsies that were not consistent with CD; and (3) 30 patients with biopsy confirmed inflammatory bowel disease. All controls were negative for IgA EMA and were not IgA deficient. Sensitivities and specificities were determined using both the manufacturers' recommended cut off points and receiver operating characteristic (ROC) analysis derived decision thresholds. The area under the curve (AUC) for each ROC plot was also calculated and compared between kits. RESULTS: In general, the h-tTG based IgA tTG ELISA kits demonstrated superior performance (especially specificity) compared with the gpl-tTG based kits, although 100% sensitivity and specificity (comparable to the IgA EMA assay) was obtained in only one recombinant h-tTG based kit. CONCLUSIONS: The use of h-tTG in IgA tTG ELISA kits is generally, but not universally, associated with superior performance. Factors other than antigen source are important in determining kit performance.

Penile intracavernosal substance abuse.

A complete workup for a 36-year-old man with unexplained inguinal adenopathy and an indurated, enlarged penis and scrotum included urine cultures for bacteria, fungi, and acid-fast bacilli; scrotal ultrasound; computed tomography of the abdomen and groin; a retrograde urethrogram; a cystogram; duplex penile Doppler blood flow studies; and a surgical inguinal lymph node dissection. Pathologic examination of the excised lymph node revealed lipoid granulomatous lymphadenitis. After receiving definitive treatment for a psychotic condition, the patient acknowledged a 2-year history of intracavernosal injection of gelatinous vitamin E.

A comparison of the mutagenicity of mainstream cigarette smoke condensates from a representative sample of the U.S. cigarette market with a Kentucky reference cigarette (K1R4F).

The Salmonella mutagenicity assay has been used to investigate the mutagenicity of cigarette smoke and cigarette smoke condensate. The Kentucky reference (K1R4F) cigarette is designed to be representative of full-flavor, low-tar cigarettes sold in the U.S. and to serve as a reference standard for comparative studies on the chemistry and biological activities of cigarette smoke and condensate. The objective of this study was to determine if the mutagenicity of mainstream smoke condensate from the K1R4F, as measured by the Salmonella mutagenicity assay, is representative of the mutagenic activity of U.S. cigarettes. Mainstream smoke condensates prepared in dimethyl sulfoxide from the K1R4F and 73 brand styles (representing greater than 70% of the total U.S. cigarette market) were assayed using Salmonella typhimurium TA98 and TA100 (+S9) at concentrations of 0, 25, 50, 75, 100, 125 and 250 micrograms/plate. Revertants/mg condensate were determined by calculating the slopes of the dose-response curves using linear and nonlinear regression models. Revertants/cigarette were determined by multiplying the revertants/mg condensate by the mg condensate/cigarette. No significant differences (p > 0.05) were observed between the mean mutagenicity of U.S. market and K1R4F mainstream smoke condensates in terms of revertants/mg condensate or revertants/cigarette. Increased variability in mutagenicity was observed among the U.S. brands versus that of the K1R4F. This is not surprising since variability among the U.S. brands would be expected to have both measurement error and brand style variability while the K1R4F variability contains only the measurement error portion. These results demonstrate that the K1R4F is a representative model for the U.S. cigarette market in comparative Salmonella mutagenicity studies using mainstream smoke condensates.

Death from massive hepatic necrosis in infectious mononucleosis.

A case is reported of a 19-year-old youth who developed infectious mononucleosis and died 17 days after the onset of the illness. At autopsy massive hepatic necrosis was found, associated with enlargement of the liver.

Appropriateness of antineutrophil cytoplasmic antibody testing in a tertiary hospital.

AIMS: To determine whether indications for ordering antineutrophil cytoplasmic antibodies (ANCA) meet the 1999 guidelines proposed for ANCA testing; and to examine the test characteristics of the ANCA test. METHODS: The indications for all ANCA tests over a two-year period were assessed and compared to the 1999 guidelines for the appropriate testing of ANCA. RESULTS: 1127 tests were examined. Overall 33.4% had an indication meeting the 1999 guidelines. The commonest non-guideline indications were ocular or orbital inflammation, liver disease and inflammatory bowel disease. All tests with a positive ANCA had indications for testing in line with the 1999 guidelines. In all but one case an ANCA associated small vessel vasculitis (AASVV) was present. CONCLUSIONS: ANCA is ordered for a wide range of guideline and non-guideline indications. No cases of AASVV would have been missed if ordering were restricted to tests meeting the 1999 guidelines.

Left coronary artery dissection: an unusual presentation.

Primary dissecting aneurysm of the left main stem coronary artery is a rare cause of coronary arterial occlusion that usually presents as sudden death or myocardial infarction in a young woman. A 32 year old woman with no signs of cardiac disease who died as the result of a right cerebral infarction was found to have coronary dissection and myocardial infarction at necropsy.

Asbestos bodies in the lung: Southampton (UK) and Wellington (New Zealand).

Two series of surgically removed and unselected necropsy lungs were examined for asbestos bodies. In the series from Southampton (UK) 30-mu sections were used and in the Wellington (New Zealand) series a modified Gold's digestion method was used for all cases, together with 30-mu sections for some. A further series of Southampton lungs was assessed by Gold's method six years after the initial study. The 30-mu section technique found asbestos bodies in 13% of Southampton men and none in women: the corresponding Wellington figures were 8% for men and nil for women. In Wellington the more sensitive digestion method found asbestos bodies in 78% of men and 63% of women. In Southampton the investigation by Gold's method found asbestos bodies in 83% of men and 74% of women. No statistically significant association was found between the number of asbestos bodies and the various types of lung carcinoma. The prevalence of asbestos in lungs removed between 1956 and 1965 did not differ significantly from its prevalence in those removed in the late 1970's. There was no significant increase in asbestos after the age of 20.

Chemiluminescence of cigarette smoke.

Chemiluminescence from cigarette smoke (aerosol) and smoke "extracts" (suspensoids) are described. The emissons from aqueous and organic suspensoids persist for hours, are proportional to oxygen solubilities, possess energy of at least 1.8 electron volts, and display characteristics which suggest that the emissions may be partially sensitized by singlet oxygen.

HIV and tuberculosis co-infection in south-western Sydney: experience from a case series.

A case series of six patients with HIV and Mycobacterium tuberculosis co-infection is presented. All patients were overseas-born and in all but one there was profound immunodeficiency. We recommend HIV screening of all cases of M. tuberculosis and a high degree of suspicion of tuberculosis in immigrants with HIV infection from endemic areas. Management problems included delayed diagnosis, rapid progression, paradoxical reactions and requirement for surgical intervention in three patients. Therapeutic complications included possible drug malabsorption, adverse events and drug interactions. M. tuberculosis was fully drug sensitive in all cases.

Copper facilitated chemiluminescence from the sulfhydryl proteins: yeast alcohol dehydrogenase, spinach ferredoxin and metallothionein.

This paper describes a copper mediated formation of active oxygen, presumably O2, from the sulfhydryl proteins, yeast alcohol dehydrogenase spinach ferredoxin and rabbit liver metallothionein which, on the addition of cyanide in the presence of acetaldehyde, displays as a chemiluminescence. These studies may provide some insights into the mechanisms of copper toxicity and provide a sensitive assay for monitoring the presence of sulfhydryl groups.

Peroxide induced chemiluminescence in an in vitro proline hydroxylation system.

This communication describes a hydrogen peroxide (HOOH) induced chemiluminescence (CL) in an in vitro aromatic (proline) hydroxylation system. The reactive components of the system are ascorbic (AA), ethylene diamine tetraacetic disodium salt (EDTA), ferrous sulfate, and HOOH. The CL is (1) nearly dissipated within three minutes, (2) enhanced and/or sustained by proline and polylysine to a greater degree than by alanine, (3) partially inhibited by a,a' dipyridyl, EDTA, and ethanol, (4) most dependent upon the presence of Fe2+, AA, and HOOH. The in vitro proline hydroxylation system is more effective than ground state oxygen in terms of the CL produced and the percent of hydroxyproline formed.

A mitochondrial chemiluminescence evoked by a novel mixed copper(II)-cyanide complex/acetaldehyde cyanohydrin chelate: a kinetic analysis suggesting a role for membrane-bound vicinal sulfhydryls.

Cyanide added to mitochondria in the presence of copper and acetaldehyde evokes a chemiluminescence which follows series pseudo-first-order kinetics: (formula; see text) An evaluation of the effects of protein (mitochondria), copper, cyanide, acetaldehyde, and oxygen on the kinetic parameters shows that k1 is influenced by protein, cyanide (at low concentrations), and oxygen while k2 is influenced by cyanide, acetaldehyde (at low, less than 11.9 mM, and high, greater than 35.6 mM, concentrations), and oxygen. The integral light increases linearly with the square root of total copper(II) and with the square of the total acetaldehyde. The sustained emissions appear to reflect an initial oxidative event mediated by a novel mixed copper(II)-cyanide complex/acetaldehyde cyanohydrin chelate. Cu(I) formed by the reduction of Cu(II), probably by mitochondrial vicinal sulfhydryls, reacts with dioxygen to form an O2-copper complex which reacts with acetaldehyde to form the acetyl-1-hydroxyhydroperoxyl radical. This radical disproportionates by the Russell mechanism to generate electronically excited singlet and triplet carbonyl functions and singlet oxygen species whose emissive relaxations to the ground state display as the observed chemiluminescence. The kinetic evidence indicates that there are two Cu(I)-oxygen cyanide complexes transferring O2- to acetaldehyde. This evidence addresses the mechanisms of autoxidation of low-molecular-weight Cu(I) complexes with dioxygen. A suggested role for the involvement of vicinal sulfhydryl groups in the reactions is shown, kinetically, by the influence of copper and acetaldehyde on the integral light.

KCN-induced urinary chemiluminescence (UCL): inhibition by ascorbic acid.

Addition of KCN or H2O2 to normal human urine resulted in chemiluminescence (CL). The CL increased with increasing concentrations of KCN and H2O2 and with increasing pH of the reaction mixture. KCN-induced UCL was markedly inhibited by exogenously added ascorbic acid (AA) and to varying degrees by glucose, albumin, tryptophan, hemoglobin and histidine. In contrast H2O2-induced UCL was significantly inhibited only by tryptophan. Mannitol and ethanol (hydroxyl radical scavengers) had little effect on either KCN-or H2O2-induced UCL. The KCN-sensitive and the H2O2-sensitive components were eluted in different positions from a Sephadex G15 column indicating chemically distinct compounds with molecular weights of less than 1500 daltons. We conclude that the UCL produced by H2O2 and KCN arise via interactions with chemically distinct compounds present in the urine.

Mitochondrial chemiluminescence elicited by acetaldehyde.

Acetaldehyde-dependent chemiluminescence has been found to be a sensitive technique for the study of superoxide and hydrogen peroxide formation in beef heart mitochondria. The system responds to ATP and antimycin A with increased emission intensities and to ADP and rotenone with decreased intensities, indicating that the chemiluminescence reflects the energy status of the mitochondrion. These effects are based on the ability of acetaldehyde to react with superoxide and hydrogen peroxide to form metastable intermediates which decay spontaneously with the emission of light. Additionally, these intermediates can react with cyanide to give alternative products which can also decay with the emission of light, the cyanide-evokable chemiluminescence. The interaction of acetaldehyde with mitochondria is complex because acetaldehyde can serve as a hydrogen source for NADH and as an inhibitor (at high concentration) of electron transport, and appears to be a reducing agent for a heat-stable site that autoxidatively generates HOOH from O2-.. Inasmuch as acetaldehyde is a metabolite of ethanol, this broad spectrum of reactivity may play a role in the hepatic and cardiac toxicity that is associated with alcoholism. The heat-stable site that generates HOOH from O2-. has been studied further and appears to contain vicinal dithiol which is primarily responsible for the cyanide-evokable chemiluminescence.