IgE-mediated hypersensitivity to cephalosporins: Cross-reactivity and tolerability of alternative cephalosporins

BACKGROUND: Studies regarding the cross-reactivity and tolerability of alternative cephalosporins in large samples of subjects with an IgE-mediated hypersensitivity to cephalosporins are lacking. OBJECTIVE: We sought to evaluate the possibility of using alternative cephalosporins in subjects with cephalosporin allergy who especially require them. METHODS: One hundred two subjects with immediate reactions to cephalosporins and positive skin test results to the responsible drugs underwent serum specific IgE assays with cefaclor and skin tests with different cephalosporins. Subjects were classified in 4 groups: group A, positive responses to 1 or more of ceftriaxone, cefuroxime, cefotaxime, cefepime, cefodizime, and ceftazidime; group B, positive responses to aminocephalosporins; group C, positive responses to cephalosporins other than those belonging to the aforementioned groups; and group D, positive responses to cephalosporins belonging to 2 different groups. Group A subjects underwent challenges with cefaclor, cefazolin, and ceftibuten; group B participants underwent challenges with cefuroxime axetil, ceftriaxone, cefazolin, and ceftibuten; and group C and D subjects underwent challenges with some of the aforementioned cephalosporins selected on the basis of their patterns of positivity. RESULTS: There were 73 subjects in group A, 13 in group B, 7 in group C, and 9 in group D. Challenges with alternative cephalosporins (ceftibuten in 101, cefazolin in 96, cefaclor in 82, and cefuroxime axetil and ceftriaxone in 22 subjects) were well tolerated. CONCLUSIONS: Cephalosporin hypersensitivity does not seem to be a class hypersensitivity. Subjects with cephalosporin allergy who especially require alternative cephalosporins might be treated with compounds that have side-chain determinants different from those of the responsible cephalosporins and have negative pretreatment skin test responses

Thermoelastic properties of zircon: Implications for geothermobarometry

A thermal-pressure equation of state has been determined for zircon (ZrSiO4) that characterizes its thermoelastic behavior at metamorphic conditions. New pressure-volume (P-V) data from a "Mud Tank"zircon have been collected from 1 bar to 8.47(1) GPa using X-ray diffraction, and elastic moduli were measured from room temperature up to 1172 K by resonance ultrasound spectroscopy. These data were fitted simultaneously with temperature-volume (T-V) data from the literature in EosFit7c using a new scaling technique. The parameters of a third-order Birch-Murnaghan EoS with a Mie-Grüneisen-Debye model for thermal pressure have compressional EoS parameters K0T = 224.5(1.2) GPa, K0T′= 4.90(31) with a fixed initial molar volume V0 = 39.26 cm3/mol and thermal parameters γ0 = 0.868(15), q = 2.37(80), and ΘD = 848(38) K. EoS parameters that describe the variation of unit-cell parameters with pressure and temperature were determined using an isothermal-type EoS. This new EoS confirms that zircons are stiffer than garnets and exhibit a much lower thermal expansion. This results in steep isomekes between zircon and garnets, which makes zircon trapped as inclusions in garnets at metamorphic conditions a good piezothermometer

Combined timed surgery and conservative management of primary necrotizing fasciitis of the breast: A case report

Objective: Rare disease Background: Necrotizing fasciitis is a life-threatening infection that involves the deep fascia and the surrounding tissue, but rarely involves the female breast. The most common treatment for necrotizing fasciitis of the breast is total mastectomy. However, the use of negative pressure wound therapy (NPWT), after surgical debridement, is reported to promote the more rapid development of granulation tissue, before reconstructive surgery. This report presents the case of a 53-year-old woman with necrotizing fasciitis of the breast who underwent combined timed surgery and conservative management. Case Report: A 53-year-old woman presented with necrotizing fasciitis of the right breast, involving the right lateral chest wall and flank. She was referred to the Intensive Care Unit (ICU) of the hospital with septic shock. After hemo-dynamic stabilization was achieved, she underwent surgical debridement. Excised breast tissues were sent for histology, and intraoperative swabs were collected and sent for microbiological examination. Intravenous anti-biotic therapy and hyperbaric oxygen therapy commenced. The patient was managed with NPWT dressings, followed by reconstructive breast surgery. The right chest and flank completely healed. Conclusions: This case has shown that early diagnosis and management of necrotizing fasciitis of the breast can be life-saving and may allow for breast conservation. Early aggressive debridement combined with NPWT dressings and re-constructive breast surgery resulted in successful wound healing and preservation of the breast with a satis-factory cosmetic outcome