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Background: Many food recalls are related to the presence of undeclared allergens and microorganisms in food products. To reduce these occurrences, portable diagnostic assay kits are available to quantitate mycotoxins, to detect allergens and gluten in foods and on environmental surfaces, and for sanitation monitoring., Objective: This article reviews diagnostic kits that can detect sources of contamination in food and ingredients as well as on surfaces and clean-in-place rinses., Method: Mycotoxins and gluten were detected using lateral flow diagnostic assays. Sanitation monitoring of surfaces was completed using a chemiluminescent assay to detect adenosine 5'-triphosphate disodium salt hydrate (ATP) and another assay to detect protein., Results: Gluten was detected at 10 ppm in spiked commodities and on wet and dry surfaces at 2.5 µg/100cm2. Deoxynivalenol was quantitated in dry distillers grains plus solubles and mean results were within two SDs of those determined by HPLC. The chemiluminescent assay had an LOD of 6 fmol of ATP and was able to detect a 1:10 000 dilution of orange juice from surfaces. The protein assay detected 5 µg of bovine serum albumin (BSA) directly applied to the sampler, 100 µg of BSA on surfaces, and detected 1:10 dilutions of Greek yogurt and raw beef from surfaces., Conclusions: Portable diagnostic kits evaluated in this work provided accurate, rapid, and sensitive results for detection of mycotoxins, gluten, proteins, and ATP. These methods can be used in facilities with minimal training and provide results that are important to ensure food safety., Highlights: Portable methods to detect gluten, mycotoxins, proteins, and ATP are presented., (© AOAC INTERNATIONAL 2020.)

Abstract: The use of virtual surgical planning and computer-aided design/computer-aided manufacturing has gained popularity in the surgical correction of craniosynostosis. This study expands the use of virtual surgical planning and computer-aided design/computer-aided manufacturing in cranial vault reconstruction by using these methods to reconstruct the anterior vault using a single endocortically-plated unit constructed from the posterior calvarium. This technique was designed to reduce the risk of undesirable contour deformities that can occur when multiple bone grafts are used to reconstruct the anterior vault and fronto-orbital rim. Six patients were included in this study, all of which had nonsyndromic craniosynostosis. Excellent aesthetic outcomes were obtained in all patients, without complication. Additionally, the placement of a single reconstructive unit constructed from the posterior calvarium was efficient, aesthetically pleasing, and minimized postoperative contour deformities secondary to bone gaps, resorption, and often palpable resorbable plates., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 by Mutaz B. Habal, MD.)

Background: Reveal® Q+ for DON is an immunochromatographic test for quantitative determination of deoxynivalenol (DON) in grains., Objective: A study was conducted to validate performance of this method for determination of DON in naturally contaminated corn and wheat and in DON-spiked corn/soy blend, soybeans, barley, malted barley, buckwheat, brown rice, sorghum, and distillers dried grain., Methods: In addition to matrix testing, LOD, linearity, selectivity, robustness, and stability/lot-to-lot consistency testing were performed., Results: The LOD was determined to be 0.014 ppm in corn and 0.037 ppm in wheat, and the LOQ 0.042 ppm in corn and 0.11 ppm in wheat. Recovery ranged from 90 to 104% across a range of reference values of 0.5 to 34.5 ppm. Linearity calculation comparing test results with reference values produced R2 values of 0.999 in both matrixes. Internal results with corn and wheat were corroborated in independent laboratory testing. For DON-spiked commodities, mean recovery across a range of DON concentration from 0.5 to 30 ppm ranged from 90 to 109%. Results of selectivity testing showed no cross-reactivity with other mycotoxins and no interference in detection of DON. Reagent lot-to-lot consistency and stability studies showed consistent results across a range of DON levels and established expiration dating for the test of 18 months after manufacture when stored under specified conditions. Conclusions and Highlights: The Reveal Q+ for DON test offers reliable performance as well as the advantages of aqueous sample extraction, procedural simplicity, minimal labor and equipment requirements, and rapid results., Conclusions: The Reveal Q+ for DON test is validated as a Performace Tested Method in Corn, Wheat, and a variety of other grains., Highlights: The test provides rapid results from a simple aqueous extraction and requires minimal labor and equipment., (© AOAC INTERNATIONAL 2020.)

Vascular malformations (VMs) of the head and neck can lead to aesthetic problems as well as cranial nerve damage, airway compromise, and vision loss. Large VMs are typically managed surgically, with sclerotherapy or embolization performed in the perioperative period to decrease the risk of excessive blood loss and minimize the size of the VM. However, this initial treatment is frequently insufficient leading to excessive blood loss intraoperatively, poorer margin visualization for the surgeon, and decreased likelihood of complete resection. As a result, resections of large VMs are often performed in a multistage approach. This article introduces a new hybrid approach for the management of head and neck VMs entailing the use of an endovascular operating room where a neuroendovascular surgeon performs embolization or sclerotherapy intraoperatively as needed in conjunction with surgical excision. Three patients with large VMs in the facial region underwent successful use of the hybrid approach. The hybrid approach improved visualization, leading to complete resection in 1 patient and nearly complete resections (70% and 90%) in the other patients. The technique also helped minimize blood loss because only the youngest patient (23 months old) required a blood transfusion. Implications of these findings include the transition from a multistaged approach for large VMs to a single-stage approach. In addition, decreases in blood loss may allow for the development and use of minimal access techniques, leading to a decrease in visible scarring for patients. We suggest the consideration of the hybrid approach for large head and neck VMs.

The AccuPoint Advanced ATP Hygeine Monitoring System was validated by an AOAC International Performance Tested MethodSM on the detection of ATP from stainless steel surfaces. Neogen Corp.'s system is a lightweight, hand-held diagnostic tool used to validate and verify a hygiene program's effectiveness by detecting organic residues remaining on surfaces and in liquids after cleaning. The system is composed of three primary components: an electronic luminometer, fully self-contained single-use samplers, and software. The system is designed to detect adenosine triphosphate (ATP) at set thresholds and to report the measurement in relative light units (RLU). These thresholds are established by a facility to reflect effective cleaning practices. The instrument compares the measured level of ATP with the established threshold and reports the results as pass, marginal, or fail. A linear dose-response in RLU was observed with pure analyte. In the matrix and microbial studies, detection levels varied depending on the matrix and microorganism tested. Independent laboratory trials confirmed pure analyte and matrix observations. Specificity testing of similar, yet different, compounds resulted in 0 RLU for all except 2'-deoxyadenosine 5'-triphosphate sodium salt, which showed markedly reduced reactivity when compared with ATP. Also, interference by these compounds was negligible. When disinfectant residues were evaluated for their effect on the test, cleaners increased RLU output to varying degrees. Stability testing showed consistent results between three independently manufactured lots and stable results through the 9 month shelf-life. Additionally, when three readers were compared using electronic light-emitting diodes as the light source, instrument variability was low (<3%). Robustness testing results provided evidence that temperature affects test performance more than shaking time, and sampler performance improves as the temperature increases to room temperature. These results provided evidence that the AccuPoint Advanced ATP Hygiene Monitoring System produces consistent and reliable data for the evaluation of sanitation program effectiveness on stainless steel surfaces in food processing and food service facilities.

Work was conducted to validate performance of the ANSR(®) for Listeria monocytogenes method in selected food and environmental matrixes. This DNA-based assay involves amplification of nucleic acid via an isothermal reaction based on nicking enzyme amplification technology. Following single-step sample enrichment for 16-24 h for most matrixes, the assay is completed in 40 min using only simple instrumentation. When 50 distinct strains of L. monocytogenes were tested for inclusivity, 48 produced positive results, the exceptions being two strains confirmed by PCR to lack the assay target gene. Forty-seven nontarget strains (30 species), including multiple non-monocytogenes Listeria species as well as non-Listeria, Gram-positive bacteria, were tested, and all generated negative ANSR assay results. Performance of the ANSR method was compared with that of the U.S. Department of Agriculture, Food Safety and Inspection Service Microbiology Laboratory Guidebook reference culture procedure for detection of L. monocytogenes in hot dogs, pasteurized liquid egg, and sponge samples taken from an inoculated stainless steel surface. In addition, ANSR performance was measured against the U.S. Food and Drug Administration Bacteriological Analytical Manual reference method for detection of L. monocytogenes in Mexican-style cheese, cantaloupe, sprout irrigation water, and guacamole. With the single exception of pasteurized liquid egg at 16 h, ANSR method performance as quantified by the number of positives obtained was not statistically different from that of the reference methods. Robustness trials demonstrated that deliberate introduction of small deviations to the normal assay parameters did not affect ANSR method performance. Results of accelerated stability testing conducted using two manufactured lots of reagents predicts stability at the specified storage temperature of 4°C of more than 1 year.

A study was conducted to validate minor reagent formulation, enrichment, and procedural changes to the ANSR(®) Listeria method, Performance-Tested Method(SM) 101202. In order to improve ease of use and diminish risk of amplicon contamination, the lyophilized reagent components were reformulated for increased solubility, thus eliminating the need to mix by pipetting. In the alternative procedure, an aliquot of the lysate is added to lyophilized ANSR reagents, immediately capped, and briefly mixed by vortexing. When three foods (hot dogs, Mexican-style cheese, and cantaloupe) and sponge samples taken from a stainless steel surface were tested, significant differences in performance between the ANSR and U.S. Food and Drug Administration Bacteriological Analytical Manual or U.S. Department of Agriculture, Food Safety and Inspection Service Microbiology Laboratory Guidebook reference culture procedures were seen with hot dogs and Mexican-style cheese after 16 h enrichment, with the reference methods producing more positive results. After 24 h enrichment, however, there were no significant differences in method performance for any of the four matrixes tested. Robustness testing was also conducted, with variations to lysis buffer volume, lysis time, and sample volume having no demonstrable effect on assay results. Accelerated stability testing was carried out over a 10-week period and showed no diminishment in assay performance. A second phase of the study examined performance of the ANSR assay following enrichment in a new medium, LESS Plus broth, designed for use with all food and environmental sample types. With the alternative LESS Plus broth, there were no significant differences in performance between the ANSR method and the reference culture procedures for any of the matrixes tested after either 16 or 24 h enrichment, although 24 h enrichment is recommended for hot dogs due to higher sensitivity. Results of inclusivity and exclusivity testing using LESS Plus broth showed that the ANSR assay is highly specific, with 100% expected results for target and nontarget bacteria.

ANSR® Listeria was previously certified as Performance Tested Method(SM) 101202 for detection of Listeria spp. on selected environmental surfaces. This study proposes a matrix extension to the method for detection of Listeria spp. in selected food matrixes. The method is an isothermal nucleic acid amplification assay based on the nicking enzyme amplification reaction technology. Following single-step sample enrichment for 16-24 h, the assay is completed in less than 50 min, requiring only simple instrumentation. Inclusivity testing was performed using a panel of 51 strains of Listeria spp., representing the species L. grayi, L. innocua, L. ivanovii, L. monocytogenes, L. seeligeri, and L. welshimeri. All strains tested were detected by the ANSR assay. Exclusivity testing of 30 strains representing non-Listeria Gram-positive bacteria yielded no evidence of cross-reactivity. Performance of the ANSR method for detection of Listeria spp. was compared to that of reference culture procedures for pasteurized liquid egg, pasteurized 2% milk, Mexican-style cheese, ice cream, smoked salmon, lettuce, cantaloupe, and guacamole. Data obtained in these unpaired studies and analyzed using a probability of detection model demonstrated that there were no statistically significant differences in results between the ANSR and reference culture methods, except for milk at 16 h and cantaloupe. In milk and smoked salmon, ANSR sensitivity was low at 16 h and therefore the recommended incubation time is 24 h. In cantaloupe, ANSR was found to be more sensitive than the reference culture method at both 16 and 24 h in independent laboratory testing. The ANSR Listeria method can be used as an accurate, rapid, and simple alternative to standard culture methods for detection of Listeria spp. in selected food types.

The generation of air-based plasmas under atmospheric plasma conditions was studied to assess their antimicrobial efficacy against commonly found pathogenic bacteria. The mixture of initial gases supplied to the plasma was found to be critical for the formation of bactericidal actives. The optimal gas ratio for bactericidal effect was determined to be 99% nitrogen and 1% oxygen, which led to a 99.999% reduction of a pathogenic strain of Escherichia coli on stainless steel surfaces. The experimental substrate, soil load on the substrate, flow rate of the gases, and addition of ethanol vapor all were found to affect antimicrobial efficacy of studied plasmas. Optical emission spectroscopy was used to identify the species that were present in the plasma bulk phase for multiple concentrations of nitrogen and oxygen ratios. The collected spectra indicate a unique series of bands present in the ultraviolet region of the electromagnetic spectrum that can be attributed to nitric oxide species known to be highly antimicrobial. This intense spectral profile dramatically changes as the concentration of nitrogen decreases.

This paper describes the results of a study to validate minor reagent formulation and procedural changes to the ANSR® Salmonella method, AOAC Performance Tested Method™ 061203. In order to improve ease of use and diminish risk of amplicon contamination, the lyophilized reagent components were reformulated for increased solubility, thus eliminating the need to mix by pipetting. In the alternative procedure, an aliquot of the lysate is added to lyophilized ANSR reagents, immediately capped, and briefly mixed by vortex. Results of the validation study with ice cream, peanut butter, dry dog food, raw ground turkey, raw ground beef, and sponge samples from a stainless steel surface showed no statistically significant differences in performance between the ANSR method and the U.S. Food and Drug Administration Bacteriological Analytical Manual or U.S. Department of Agriculture-Food Safety and Inspection Services Microbiology Laboratory Guidebook reference culture procedures. Results of inclusivity and exclusivity testing were unchanged from those of the original validation study; exclusivity was 100% and inclusivity was 99.1% with only a single strain of Salmonella Weslaco testing negative. Robustness testing was also conducted, with variations to lysis buffer volume, lysis time, and sample volume having no demonstrable effect on assay results.

This study represents a proposal to extend the matrix claims for the ANSR Salmonella test, Performance Tested Method 061203. The test is based on the nicking enzyme amplification reaction (NEAR) isothermal nucleic acid amplification technology. The assay platform features simple instrumentation, minimal labor, and following a single-step 16-24 h enrichment (depending on sample type), an extremely short assay time of 30 min including sample preparation. Detection is real-time using fluorescent molecular beacon probes. ANSR Salmonella was originally validated for detection of Salmonella spp. in chicken carcass rinse, raw ground turkey, raw ground beef, hot dogs, and oat cereal, and on stainless steel, plastic, sealed concrete, ceramic tile, and rubber surfaces. The matrixes tested in this study include pet food, ice cream, soy flour, raw almonds, peanut butter, spinach, black pepper, raw frozen shrimp, cocoa powder, and pasteurized dried egg. In unpaired comparative testing there were no statistically significant differences in the number of positive results obtained with the ANSR and the reference culture methods. Enrichment for 16 h was effective for all commodities tested except ice cream, black pepper, dried pasteurized egg, and 375 g samples of dry pet food, for which enrichment for 24 h is indicated.

ANSR Salmonella is a new molecular diagnostic assay for detection of Salmonella spp. in foods and environmental samples. The test is based on the nicking enzyme amplification reaction (NEAR) isothermal nucleic acid amplification technology. The assay platform features simple instrumentation, minimal labor, and, following a single-step 10-24 h enrichment (depending on sample type), an extremely short assay time of 30 min, including sample preparation. Detection is real-time using fluorescent molecular beacon probes. Inclusivity testing was performed using a panel of 113 strains of S. enterica and S. bongori, representing 109 serovars and all genetic subgroups. With the single exception of the rare serovar S. Weslaco, all serovars and genetic subgroups were detected. Exclusivity testing of 38 non-salmonellae, mostly Enterobacteriaceae, yielded no evidence of cross-reactivity. In comparative testing of chicken carcass rinse, raw ground turkey, raw ground beef, hot dogs, and oat cereal, there were no statistically significant differences in the number of positive results obtained with the ANSR and the U.S. Department of Agriculture-Food Safety and Inspection Service or U.S. Food and Drug Administration/Bacteriological Analytical Manual reference culture methods. In testing of swab or sponge samples from five different environmental surfaces, four trials showed no statistically significant differences in the number of positive results by the ANSR and the U.S. Food and Drug Administration/ Bacteriological Analytical Manual reference methods; in the trial with stainless steel surface, there were significantly more positive results by the ANSR method. Ruggedness experiments showed a high degree of assay robustness when deviations in reagent volumes and incubation times were introduced.

A study was conducted to determine the efficacy of the Soleris Non-fermenting-Total Viable Count (NF-TVC) automated growth-based method for semiquantitative detection of mesophilic, aerobic microorganisms in a variety of food products. A probability of detection (POD) statistical model was used to compare Soleris results at multiple test thresholds (dilutions) with aerobic plate counts determined using reference dilution plating procedures. Nine naturally contaminated food products were tested, with Soleris testing performed at three or four threshold levels for each food. Using the POD model, all Soleris test results were in statistical agreement with the reference plating procedures with the exception of a single threshold level in two trials with black pepper, and a single threshold level in the independent laboratory trial with cheesecake. Results of ruggedness testing showed that the Soleris method produced accurate results even when minor variances in operating parameters, including sample volume and incubation temperature, were introduced. Results of the internal and independent laboratory validation studies showed that the Soleris NF-TVC method can be used as an accurate alternative to conventional dilution plating procedures for evaluation of microbial counts at threshold levels, while saving 24 h or more in analysis time.

Reveal E. coli 2.0 is a new lateral-flow immunodiagnostic test for detection of E. coli O157:H7 and O157:NM in raw beef trim and ground beef. Compared with the original Reveal E. coli O157:H7 assay, the new test utilizes a unique antibody combination resulting in improved test specificity. The device architecture and test procedure have also been modified, and a single enrichment protocol was developed which allows the test to be performed at any point during an enrichment period of 12 to 20 h. Results of inclusivity and exclusivity testing showed that the test is specific for E. coli serotypes O157:H7 and O157:NM, with the exception of two strains of O157:H38 and one strain of O157:H43 which produced positive reactions. In internal and independent laboratory trials comparing the Reveal 2.0 method to the U.S. Department of Agriculture-Food Safety and Inspection Service reference culture procedure for detection of E. coli O157:H7 in 65 and 375 g raw beef trim and ground beef samples, there were no statistically significant differences in method performance with the exception of a single internal trial with 375 g ground beef samples in which the Reveal method produced significantly more positive results. There were no unconfirmed positive results by the Reveal assay, for specificity of 100%. Results of ruggedness testing showed that the Reveal test produces accurate results even with substantial deviation in sample volume or device incubation time or temperature. However, addition of the promoter reagent to the test sample prior to introducing the test device is essential to proper test performance.

A collection of 54 clinical and agricultural isolates of Burkholderia cenocepacia was analyzed for genetic relatedness by using multilocus sequence typing (MLST), pathogenicity by using onion and nematode infection models, antifungal activity, and the distribution of three marker genes associated with virulence. The majority of clinical isolates were obtained from cystic fibrosis (CF) patients in Michigan, and the agricultural isolates were predominantly from Michigan onion fields. MLST analysis resolved 23 distinct sequence types (STs), 11 of which were novel. Twenty-six of 27 clinical isolates from Michigan were genotyped as ST-40, previously identified as the Midwest B. cenocepacia lineage. In contrast, the 12 agricultural isolates represented eight STs, including ST-122, that were identical to clinical isolates of the PHDC lineage. In general, pathogenicity to onions and the presence of the pehA endopolygalacturonase gene were detected only in one cluster of related strains consisting of agricultural isolates and the PHDC lineage. Surprisingly, these strains were highly pathogenic in the nematode Caenorhabditis elegans infection model, killing nematodes faster than the CF pathogen Pseudomonas aeruginosa PA14 on slow-kill medium. The other strains displayed a wide range of pathogenicity to C. elegans, notably the Midwest clonal lineage which displayed high, moderate, and low virulence. Most strains displayed moderate antifungal activity, although strains with high and low activities were also detected. We conclude that pathogenicity to multiple hosts may be a key factor contributing to the potential of B. cenocepacia to opportunistically infect humans both by increasing the prevalence of the organism in the environment, thereby increasing exposure to vulnerable hosts, and by the selection of virulence factors that function in multiple hosts.

Purpose: The purpose of this study is to evaluate the coverage patterns of whole and split flexor carpi ulnaris (FCU) pedicle muscle flaps for posterior elbow soft-tissue defects., Methods: Seventeen fresh-frozen cadaveric upper extremities were used. The whole FCU was raised to the dominant vascular pedicle and transposed proximally over the olecranon. The widths of coverage at 2-cm distances about the posterior elbow were measured. Widths were also measured after making 3 longitudinal cuts in the fascia and after suturing the muscle to adjacent soft tissue under tension. The FCU was also split into its ulnar and humeral heads along the central tendon. The larger ulnar head was transposed and the widths again measured. Mid-forearm circumference, elbow circumference, and ulnar length were assessed for ability to predict flap width., Results: The whole muscle under no tension provided an average of 2.7 cm width coverage at the tip of the olecranon process. Cutting the fascia provided approximately 15% additional width and suturing the muscle to the surrounding soft tissue an additional 25%, to approximately 4 cm. The isolated FCU ulnar head provided approximately 75% of the width of the entire muscle. Mid-forearm circumference was the most predictive of flap width, and divisors were generated that improved the accuracy of predicting the width for outlier specimens. The dominant pedicle was a consistent distance relative to the end of the central tendon and the olecranon tip., Conclusions: The whole and split FCU pedicle flaps provide predictable coverage for 2- to 4-cm posterior elbow soft-tissue defects. For especially large and small arms, the divisors improve accuracy in predicting flap width. Consistent locations of the olecranon tip and the end of the central tendon in relation to the dominant pedicle make them useful surgical landmarks.

Previous studies have demonstrated that an Sp1 binding site polymorphism in the collagen type I gene (COLIA1) is related to reduced bone mineral density (BMD) and osteoporotic fractures in certain populations, particularly in the elderly. We have examined the relationship among these COLIA1 Sp1 alleles, BMD, quantitative ultrasound properties of bone, and fractures in a population-based cohort of elderly women from the UK. The study group comprised 314 women aged 75 years and over who agreed to participate in a clinical study of bisphosphonate therapy in preventing bone loss at the hip. Women were enrolled regardless of the presence or absence of osteoporosis, but those with other diseases that might affect skeletal metabolism were excluded. The genotype distribution for the Sp1 polymorphism was in Hardy-Weinberg equilibrium (SS - 78%; Ss - 20%; ss - 2%) but the proportion of individuals who carried the "s" allele (22%) was significantly lower than previously observed in another study of the UK population (37.1%) (P < 0.001). There were no significant associations between COLIA1 genotypes and metacarpal cortical index, BMD of the forearm, tibial SOS, calcaneal SOS, or calcaneal BUA. While there was a trend towards lower BMD values at the hip in patients with Ss and ss genotypes, this was not statistically significant (SS = 0.721 +/- 0.14; Ss = 0.704 +/- 0.13; ss = 0.683 +/- 0.20 P = 0.6). Prevalent vertebral fractures occurred in 22% of subjects and prior fractures of the wrist, ankle, and hip were reported by 20%, but there was no significant difference in COLIA1 genotype distribution between fracture patients and controls. We conclude that COLIA1 Sp1 alleles are not significantly associated with BMD, ultrasound properties of bone, or fractures in this population-based sample of elderly women.

The allergens produced by the dust mites of the Dermatophagoides genus are now recognized as one of the major allergens in house dust. Quantification of those allergens helps to evaluate the effectiveness of avoidance measures and specific treatments aimed at the reduction of the mites and their allergens. The present study was undertaken to compare the level of D. farinae allergen collected by a standard vacuum cleaner with a disposable bag and the level of allergen collected by a hand-held vacuum equipped with a special filter. Samples were obtained from the main living area of 18 homes of patients allergic to D. farinae. Using a hand-held vacuum especially equipped with a removable micropore filter, a 2-m2 area of carpet was vacuumed for two minutes and an identical sample was collected from the major upholstered piece of furniture in the room. A third sample was obtained with an upright vacuum fitted with a clean disposable bag. The dust collected was extracted in phosphate buffered saline and resultant extracts were assayed for D. farinae allergen content by microtiter plate RAST inhibition assay. Results from these assays showed a large interhome variability regardless of sampling technique, but intrahome sampling showed remarkable consistency. A linear regression analysis demonstrated all of the comparisons correlated at a probability level of P less than .05. We conclude that dust mite allergen levels collected in a disposable bag vacuum cleaner are reliable indicators of the level of house dust mites present in the homes of patients.

The purpose of this study was to determine the role of the house dust mite. Dermatophagoides pteronyssinus (Dp) and Dermatophagoides farinae (Df), in allergic diseases on the island of St. Lucia. Dust samples were taken from living quarters of patients and hospital volunteers. The level of Df antigen in these living quarters was measured by RAST inhibition. All samples showed Df antigen within a large range of values. Prick tests were done to house dust mite and molds on 91 patients with suspected allergic disease with 63 (69%) reacting to at least one antigen. Of these, 56 (88.9%) reacted to one or both mites. House dust mite is a major allergen in St. Lucia.

The factors that produce dark pigmentation of the oral soft tissues are described. Examples are given of aberrations of the melanin-forming cells in the oral cavity and a new case of oral blue nevus is added to the literature. A unique case of localized melanosis of the tongue is described clinically and histopathologically.

In order to determine the diagnostic performance of the Quidel Allergen Screen (QAS), 43 patients characterized by standard skin prick test and intradermal testing for atopic sensitivity were evaluated, in parallel, using Phadebas RAST and QAS to detect the presence of serum IgE. The Quidel Allergen Screen and RAST were compared with the investigator's clinical assessment. The differences between QAS and RAST are not statistically significant. The QAS appears to be equal to the Phadebas RAST in sensitivity and specificity and thus offers a rapid, easily interpreted in vitro method for the detection of specific serum IgE.

The aetiology, diagnosis and treatment of peripheral facial nerve palsy are discussed. Four cases of facial nerve palsy following dental procedures are reported. Following a revision of the world literature during the last 23 years, the 25 cases of facial nerve palsy documented are analysed and divided into four groups on the basis of aetiology, speed of onset and recovery and modes of treatment suggested.

Farmer's lung is a serious disabling pulmonary disease found in agricultural workers. The disease is believed to be a hypersensitivity to the thermophilic actinomycetes, principally Thermopolyspora polyspora. This organism is difficult to stain with the usual bacteriological stains and thus far has not been demonstrated in the lung tissue by microscopic methods. In this paper, it is demonstrated that the fluorescent-antibody technique is a simple method for the positive identification of T. polyspora. The technique can also be used as a rapid screening test for the detection of antibodies to T. polyspora in the patient's serum. In addition, it opens up the possibility of the identification of T. polyspora in the lung tissue of patients with farmer's lung and makes available a means for the study of the immunological reaction in the lung parenchyma. No false positive or cross-reactions with Thermoactinomyces vulgaris or Streptomyces griseus could be demonstrated.