Evangelo Frigas

The eosinophil and the pathophysiology of asthma

Eosinophilia of lung and blood associated with injury to the mucociliary escalator and excessive shedding of bronchial epithelium are hallmarks of both allergic and nonallergic asthma. In vitro, the eosinophil granule major basic protein (MBP) is toxic to helminths and to mammalian cells, including human respiratory epithelium. The MBP-mediated damage to the respiratory epithelium consists of desquamation and frank destruction of ciliated cells. Increased sputum MBP concentration is a good marker for asthma, and patients treated for acute asthma have high levels of MBP in their sputa, which decrease after treatment. Peak sputum MBP levels approximate concentrations toxic to respiratory epithelium in vitro. In the lungs of patients who had died of asthma, MBP has been localized outside of the eosinophil in association with damage to the epithelium. Overall, these and other findings suggest the hypothesis that the eosinophil mediates damage to the respiratory epithelium and is the prime effector cell in the pathophysiology of asthma.

The eosinophilic leukocyte and the pathology of fatal bronchial asthma : Evidence for pathologic heterogeneity

Classically, bronchial asthma is associated with peripheral blood eosinophilia and striking eosinophilia of bronchial tissues and sputum. Evidence exists that eosinophil degranulation commonly occurs during bronchial asthma and eosinophil granule proteins are discharged onto damaged bronchial epithelium. Analyses of 10 patients with fatal asthma showed striking eosinophil participation in eight, whereas two patients showed marked epithelial desquamation in the virtual absence of eosinophils. These results point to the possibility that a pathologic heterogeneity exists in fatal bronchial asthma, with most, but not all, patients showing evidence of eosinophil participation.

Bronchial challenge with formaldehyde gas: lack of bronchoconstriction in 13 patients suspected of having formaldehyde-induced asthma

We studied 13 selected patients with symptoms suggestive of asthma who suspected exposure to formaldehyde as a cause. These patients had a history of exposure to formaldehyde gas which either coincided with the onset of or aggravated their symptoms of asthma. The levels of exposure at their homes or at work ranged from 0.1 to 1.2 parts per million (ppm) of formaldehyde gas. The patients were tested with bronchial challenges of 0.1-, 1-, and 3-ppm concentrations of formaldehyde gas and randomly interspersed room-air placebos. The formaldehyde gas or placebo was delivered via a Dynacalibrator . The period of exposure to formaldehyde gas or placebo with each challenge was 20 minutes. Pulmonary function was measured before and for 24 hours after each bronchial challenge. No patient had a significantly greater decrease in the forced expiratory volume in 1 second after exposure to formaldehyde than after exposure to air. In no case were we able to substantiate that exposure to formaldehyde gas (3 ppm or less) was indeed causing or aggravating the asthmatic symptoms.

Preoperative evaluation of patients with history of allergy to penicillin: Comparison of 2 models of practice

OBJECTIVE To study whether allergy consultation and penicillin allergy skin testing affects the selection of antibacterial prophylaxis perioperatively in surgical patients with history of allergy to penicillin (HOAP). PATIENTS AND METHODS From January 1 through June 30, 2004, we compared 2 different models of practice at our institution. At the Preoperative Evaluation Clinic (POEC), all patients with HOAP are evaluated by an allergist and undergo skin testing for allergy to penicillin. At other (non-POEC) preoperative evaluation settings (OPES), patients with HOAP do not undergo allergy consultation and penicillin skin testing before surgery. Of the 4889 patients screened at the POEC during the study period, 412 consecutive patients with HOAP were included in the study. Of the 416 patients screened at OPES, 69 consecutive patients with HOAP were studied. Logistic regression was used to assess whether allergy consultation was associated with the choice of antibiotic for antibacterial prophylaxis perioperatively, after adjusting for age, sex, and type of surgery. RESULTS Perioperative cephalosporin use was greater among patients screened at POEC vs those screened at OPES (70% vs 39%, P<.001 unadjusted; P=.04 adjusted for age, sex, and type of surgery). Vancomycin use was lower for patients screened at POEC vs those screened at OPES (10% vs 28%, P<.001 unadjusted; P=.03 adjusted). CONCLUSION For patients with HOAP, evaluation at the POEC was associated with increased use of cephalosporin and decreased use of vancomycin.

Three-dimensional volumetric computed tomographic scoring as an objective outcome measure for chronic rhinosinusitis: clinical correlations and comparison to Lund-Mackay scoring.

We aimed to test the hypothesis that three‐dimensional (3D) volume‐based scoring of computed tomography (CT) images of the paranasal sinuses was superior to Lund‐Mackay CT scoring of disease severity in chronic rhinosinusitis (CRS). We determined correlation between changes in CT scores (using each scoring system) with changes in other measures of disease severity (symptoms, endoscopic scoring, and quality of life) in patients with CRS treated with triamcinolone.

Acute Urticaria and Angioedema Diagnostic and Treatment Considerations

Urticaria is defined as wheals consisting of three features: (i) central swelling of various sizes, with or without surrounding erythema; (ii) pruritus or occasional burning sensations; and (iii) the skin returning to normal appearance, usually within 1–24 hours. Angioedema is defined as: (i) abrupt swelling of the lower dermis and subcutis; (ii) occasional pain instead of pruritus; (iii) commonly involving the mucous membranes; and (iv) skin returning to normal appearance, usually within 72 hours. Acute urticaria and angioedema is defined by its duration (<6 weeks) comparedwith chronic urticaria and angioedema. The most common causes are infections, medications, and foods. The best tools in the evaluation of these patients are a comprehensive history and physical examination. There are a variety of skin conditions that may mimic acute urticaria and angioedema and the various reaction patterns associated with different drugs. Oral antihistamines are first-line treatment. In the event of a life-threatening reaction involving urticaria with angioedema, epinephrine may be needed to stabilize the patient. This review focuses on the value of a comprehensive clinical evaluation at the onset of symptoms. It underscores the importance of coordination of care among physicians, and the development of an action plan for evidence-based investigations, diagnosis, and therapy.

Clinical outcome in the use of cephalosporins in pediatric patients with a history of penicillin allergy.

Background: The risk of cephalosporin administration in patients with a history of penicillin allergy is unclear. Few studies have looked at the risk of cephalosporin administration in children following penicillin skin testing for suspected penicillin allergy. The goal of this study was to determine whether children with penicillin allergy were at increased risk for adverse drug reactions when administered a cephalosporin. Methods: A retrospective chart review was conducted in pediatric patients (≤18 years) with a history of penicillin allergy and a positive or negative penicillin skin test who were administered a cephalosporin after testing. Charts were reviewed for adverse drug reactions to the cephalosporin. Results: A total of 173 patients (91 males) were included in this study. The mean age of the patients was 4.1 ± 3.1 years. Twenty-one patients (12%) tested positive in a penicillin skin test and 152 patients (88%) tested negative. One patient with a negative penicillin skin test (0.7%) had an adverse drug reaction (eye swelling) to cephalexin. None of the patients with a positive penicillin skin test who received a course of cephalosporin had an adverse drug reaction. Conclusion: Among all patients with a history of penicillin allergy (penicillin skin test positive and negative), only 1 person had an adverse drug reaction. Further large prospective studies examining the safety of administering cephalosporins in pediatric patients with confirmed penicillin allergy are needed.

Effect of lodoxamide ethyl on allergy skin tests

Lodoxamide ethyl is a new cromolyn-like drug which prevents antigen-induced mediator release from mast cells and antigen-induced bronchoconstriction in sensitive animals and man. The purpose of this study was to determine the effect of a single administration of lodoxamide ethyl on allergy skin tests. The effect of this drug on allergy skin testing was studied in a double-blind design on ten adult subjects allergic to ragweed. Serial end-point titrations with short ragweed extract and with histamine were performed after a placebo and 1- and 3-mg capsules of lodoxamide ethyl. The immediate wheal-and-flare responses as well as the late allergic reaction were recorded. No statistically significant difference was found between lodoxamide ethyl and placebo in the suppression of the allergen-induced immediate wheal-and-flare response or the late allergic reaction. Furthermore, 1 and 3 mg of oral lodoxamide ethyl did not inhibit the histamine-induced cutaneous reactions.