Severe adverse reactions to dental local anaesthetics: systemic reactions

BACKGROUND

Occasionally, patients suffer systemic adverse effects from injections of local anaesthetic solutions. This may range from minor transient vasovagal attacks to life-threatening collapse.

METHODS

The suspected adverse reactions reported to the Office of Product Review of the Therapeutic Goods Administration (TGA) were analysed in detail.

RESULTS

There was a high incidence (70%) of adverse reactions associated with prilocaine, which is much greater than its market share (less than 20%). There is a tendency to consider all systemic adverse reactions as being 'allergic' reactions although this is rarely the case. Syncope, cardiovascular and central nervous system reactions are much more common. There is also a risk of methaemoglobinaemia to prilocaine and articaine. A small series of cases referred to one of the authors were also reported.

CONCLUSIONS

Recommendations are made as to the prevention, acute care and subsequent investigation of adverse reactions. The most important conclusion is not to just label the response as allergic and to use an alternative agent. Detailed investigation and reporting should be made for all cases of suspected severe adverse reaction to local anaesthetic agents.

Refinement of the Region for Split Hand/Foot Malformation 5 on 2q31.1

Background: Deletions that encompass 2q31.1 have been proposed as a microdeletion syndrome with common clinical features, including intellectual disability/developmental delay, microcephaly, cleft palate, growth delay, and hand/foot anomalies. In addition, several genes within this region have been proposed as candidates for split hand-foot malformation 5 (SHFM5). Methods: To delineate the genotype-phenotype correlation between deletions of this region, we identified 14 individuals with deletions at 2q31.1 detected by microarray analysis for physical and developmental disabilities. Results: All subjects for whom detailed clinical records were available had neurological deficits of varying degree. Seven subjects with deletions encompassing the HOXD cluster had hand/foot anomalies of varying severity, including syndactyly, brachydactyly, and ectrodactyly. Of 7 subjects with deletions proximal to the HOXD cluster, 5 of which encompassed DLX1/DLX2, none had clinically significant hand/foot anomalies. In contrast to previous reports, the individuals in our study did not display a characteristic gestalt of dysmorphic facial features. Conclusion: The absence of hand/foot anomalies in any of the individuals with deletions of DLX1/DLX2 but not the HOXD cluster supports the hypothesis that haploinsufficiency of the HOXD cluster, rather than DLX1/DLX2, accounts for the skeletal abnormalities in subjects with 2q31.1 microdeletions.

Two newly identified cat allergens: the von Ebner gland protein Fel d 7 and the latherin-like protein Fel d 8

INTRODUCTION

Characterization of the complete IgE binding spectrum of cat allergens is important for the development of improved diagnosis and effective immunotherapeutics. While Fel d 1 remains unchallenged as the major cat allergen, we now report the isolation of two new allergens capable of binding similar concentrations of IgE in the allergic sera of some individuals.

MATERIALS AND METHODS

Cat tongue and submandibular salivary gland cDNA libraries were screened by DNA hybridisation and IgE immunoassay. The isolated DNA fragments were sub-cloned into an E. coli expression system and the IgE reactivity was examined with human cat-allergic sera using a DELFIA IgE quantitation assay.

RESULTS

Fel d 7, an 18 kDa von Ebner gland protein Can f 1 homologue, was isolated from the tongue library. Fel d 8, a 24-kDa latherin-like protein with homology to Equ c 5, was isolated from the submandibular library. The frequency of IgE binding of cat-allergic sera to recombinant Fel d 1, 7 and 8 was 60.5, 37.6 and 19.3%, respectively. Inhibition studies indicated some IgE binding cross-reactivity between Fel d 7 and dog dander extracts.

DISCUSSION

The study reports the isolation and characterization of two new cat allergens. The isolation of these allergens provides the opportunity to determine the role that IgE binding proteins other than Fel d 1 play in cat-allergic disease. For cat-allergic individuals with moderate to mild rhinoconjunctivitis these allergens may play a more important role in the manifestation of their allergic disease.

Clinical and demographic factors associated with fractures among older Americans

Medicare claims data were used to investigate associations between history of previous fractures, chronic conditions, and demographic characteristics and occurrence of fractures at six anatomic sites. The study confirmed previously established associations for hip and spine fractures and identified several new associations of interest for nonhip, nonspine fractures.

INTRODUCTION

This study investigates the associations of a history of fracture, comorbid chronic conditions, and demographic characteristics with incident fractures among Medicare beneficiaries. The majority of fracture incidence studies have focused on the hip and on white females. This study examines a greater variety of fracture sites and more population subgroups than prior studies.

METHODS

We used Medicare claims data to examine the incidence of fracture at six anatomic sites in a random 5% sample of Medicare beneficiaries during the time period 2000 through 2005.

RESULTS

For each type of incident fracture, women had a higher rate than men, and there was a positive association with age and an inverse association with income. Whites had a higher rate than nonwhites. Rates were lowest among African-Americans for all sites except ankle and tibia/fibula, which were lowest among Asian-Americans. Rates of hip and spine fracture were highest in the South, and fractures of other sites were highest in the Northeast. Fall-related conditions and depressive illnesses were associated with each type of incident fracture, conditions treated with glucocorticoids with hip and spine fractures and diabetes with ankle and humerus fractures. Histories of hip and spine fractures were associated positively with each site of incident fracture except ankle; histories of nonhip, nonspine fractures were associated with most types of incident fracture.

CONCLUSIONS

This study confirmed previously established associations for hip and spine fractures and identified several new associations of interest for nonhip, nonspine fractures.

Blood-brain barrier permeability assessed by perfusion CT predicts symptomatic hemorrhagic transformation and malignant edema in acute ischemic stroke

BACKGROUND AND PURPOSE

SHT and ME are feared complications in patients with acute ischemic stroke. They occur >10 times more frequently in tPA-treated versus placebo-treated patients. Our goal was to evaluate the sensitivity and specificity of admission BBBP measurements derived from PCT in predicting the development of SHT and ME in patients with acute ischemic stroke.

MATERIALS AND METHODS

We retrospectively analyzed a dataset consisting of 32 consecutive patients with acute ischemic stroke with appropriate admission and follow-up imaging. We calculated admission BBBP by using delayed-acquisition PCT data and the Patlak model. Collateral flow was assessed on the admission CTA, while recanalization and reperfusion were assessed on the follow-up CTA and PCT, respectively. SHT and ME were defined according to ECASS III criteria. Clinical data were obtained from chart review. In our univariate and forward selection-based multivariate analysis for predictors of SHT and ME, we incorporated both clinical and imaging variables, including age, admission NIHSS score, admission blood glucose level, admission blood pressure, time from symptom onset to scanning, treatment type, admission PCT-defined infarct volume, admission BBBP, collateral flow, recanalization, and reperfusion. Optimal sensitivity and specificity for SHT and ME prediction were calculated by using ROC analysis.

RESULTS

In our sample of 32 patients, 3 developed SHT and 3 developed ME. Of the 3 patients with SHT, 2 received IV tPA, while 1 received IA tPA and treatment with the Merci device; of the 3 patients with ME, 2 received IV tPA, while 1 received IA tPA and treatment with the Merci device. Admission BBBP measurements above the threshold were 100% sensitive and 79% specific in predicting SHT and ME. Furthermore, all patients with SHT and ME--and only those with SHT and ME--had admission BBBP measurements above the threshold, were older than 65 years of age, and received tPA. Admission BBBP, age, and tPA were the independent predictors of SHT and ME in our forward selection-based multivariate analysis. Of these 3 variables, only BBBP measurements and age were known before making the decision of administering tPA and thus are clinically meaningful.

CONCLUSIONS

Admission BBBP, a pretreatment measurement, was 100% sensitive and 79% specific in predicting SHT and ME.

Abstract P1-03-12: The First Reproducible Model of Primary Human Ductal Carcinoma In Situ (DCIS) Using the Mouse Intraductal (MIND) Method

Past studies of the molecular mechanisms regulating human DCIS progression to invasion have been limited by a lack of suitable human models. The current models have not utilized primary human DCIS placed in their natural microenvironment, i.e., inside the mammary ducts, and do not mimic the heterogeneity of human DCIS. Previously, we reported the development of a mouse xenograft model using established breast DCIS cell lines, SUM-225 and DCIS.COM by the mouse intraductal (MIND) method. MIND involves injection of human DCIS cells into the primary ducts of immunodeficient mouse mammary glands via the nipple. In this study we demonstrate the reproducible growth of human primary DCIS cells derived from patient biopsy samples using the MIND model. Core biopsies from consenting patients are processed to isolate the epithelial cell component and injected. To date, 69 patients have consented to provide core biopsy tissue and we have received tissue from 38. Of these, 14 samples have been confirmed as positive for DCIS, and 2 as atypical hyperplasia, based on the pathology report of adjacent biopsies. The biopsy samples were heterogeneous with respect to ER, PR, Ki67, Her-2 and histology. A total of 24 mammary glands from immunodeficient mice have been injected with these cells and analyzed for growth by immunofluorescent (IF) with antibodies directed at human-specific cytokeratin-5 and/or 19 and smooth muscle actin.

Table 1. Summary of grewlh of human primary biopsies in (tie MIND xenograft

The average number of cells recovered per mg of tissue are shown in Table 1. Biopsies diagnosed as normal yielded only 91±34 cells/mg compared with most DCIS cases that showed an average cell number of 971 per mg tissue. Our results indicate that human DCIS and hyperplasia cells from biopsy samples are capable of growing within the NOD-SCID IL2Rgammanull (NSG) mouse mammary ducts. NSG mice mammary ducts are more suitable hosts for the growth of human primary DCIS cells, compared to SCID-Beige. Furthermore, the higher number of cells recovered following digestion predicted the positive DCIS growth rate. DCIS cells formed single and multi-layered epithelium inside the ducts and were heterogeneous with respect to the expression of human specific cytokeratins. The MIND xenografts recapitulated the patient's original DCIS as evidenced by IF staining for the biomarkers ER and Her-2 in the primary human biopsies and MIND xenografts. These results provide the first reproducible model of primary human DCIS for studying the temporal processes of early breast cancer progression. Future experiments will characterize the cellular basis for the subtypes of DCIS and delineate the distinct molecular and cellular mechanisms of early breast cancer invasion, and cancer stem cell growth and self-renewal.