Effect of allergen immunotherapy practice parameters on cat extract prescribing patterns, 1993-2009.

BACKGROUND: Cat extract allergen immunotherapy (AIT) is an effective treatment for cat allergy. The prescribed dose for cat AIT varies among prescribers, despite published data supporting an effective dose range. The original practice parameter published in December 1996 did not recommend a dose of cat allergen, but updates in January 2003 and September 2007 recommend cat extract dose ranges of 2,000 to 3,000 BAU and 1,000 to 4,000 BAU, respectively. OBJECTIVE: To describe the prescribing patterns for cat AIT among practicing allergists in a large health care system and the effect of practice parameters on these patterns. METHODS: A total of 27,788 prescriptions were analyzed to determine the date and amount of maintenance dose cat allergen prescribed. The data were subdivided into periods before and after the 3 published AIT practice parameters. RESULTS: From January 2003 to September 2007, 1,810 prescriptions (18.0%) were written in the recommended range. From September 2007 to May 2009, 3,143 prescriptions (82.6%) were written in the recommended range. Cat AIT maintenance doses were 1,000 to 4,000 BAU 22.1% of the time before January 2003, 61.8% from January 2003 to September 2007, and 82.6% from September 2007 to May 2009. CONCLUSIONS: In this large systemic evaluation of cat AIT prescribing patterns, maintenance dose recommendations in the AIT practice parameters were associated with changes in the prescribing patterns for cat AIT. Most prescriptions for cat AIT were inconsistent with recommended doses in the AIT practice parameters between 2003 and 2007. Dosing within recommended ranges improved after 2007, in part due to a widening of the recommended dose range.

Imported fire ant immunotherapy prescribing patterns in a large health care system during a 17-year period.

BACKGROUND: No large evaluation has been performed of the maintenance vial concentration commonly used by physicians when prescribing imported fire ant (IFA) immunotherapy since the publication of the first Stinging Insect Hypersensitivity Practice Parameter 10 years ago. OBJECTIVE: To describe the prescribing patterns for IFA immunotherapy among practicing allergists in a large health care setting and the impact of published Practice Parameter recommendations. METHODS: Data from the US Army Centralized Allergen Extract Laboratory were analyzed to determine IFA immunotherapy prescribing patterns from 1990 to May 2007. This extract laboratory provides prescriptions for more than 320 US Department of Defense, US Department of Veterans Affairs, and US Public Health Service clinics. RESULTS: A total of 1,091 patients were given 1,437 new or revised prescriptions for IFA immunotherapy. Monotherapy for Solenopsis invicta and Solenopsis richteri was prescribed in 169 (11.8%) and 3 (0.1%) instances, respectively, with the remainder of patients given both IFA antigens. The most commonly prescribed maintenance vial dose was 0.5 mL of a 1:200 (wt/vol) dilution, accounting for 36.3% of prescriptions. A total of 17.3% of prescriptions had a maintenance vial dose of 0.5 mL of a 1:100 (wt/vol) dilution, 4.6% had a dilution of 1:10 (wt/vol), and 50.6% had a dilution between 1:10 and 1:100 (wt/vol). The mean starting dose was 4.4 10-fold dilutions below the maintenance dose (5.4 vials per treatment set). CONCLUSIONS: The most commonly prescribed maintenance dose was 0.5 mL of a 1:200 (wt/vol) dilution, although most prescriptions used a maintenance dose consistent with recommended dosing in the Stinging Insect Practice Parameters. Both IFA antigens were used by most physicians. Further study evaluating the effective dose range for IFA immunotherapy is needed.

Risk of angioedema with angiotensin receptor blockers in patients with prior angioedema associated with angiotensin-converting enzyme inhibitors: a meta-analysis.

BACKGROUND: Patients who have angioedema after taking angiotensin-converting enzyme inhibitors (ACE-Is) have been reported to develop angioedema when taking an angiotensin receptor blocker (ARB), but few studies quantify the risk. OBJECTIVE: To perform a systematic review of the literature. METHODS: A literature search was performed in MEDLINE, EMBASE, BIOSIS, and Current Contents, with no limitations from January 1990 to May 2007. Any article that described a cohort of patients who had angioedema after taking an ACE-I, were subsequently exposed to an ARB, and were followed for a least 1 month were included. The percentage of patients who had angioedema was abstracted from each article, and confidence intervals were calculated using the exact binomial method. The pooled percentage was calculated with the inverse variance method. RESULTS: Two-hundred fifty-four unique articles were identified, and 3 articles met inclusion criteria, which described 71 patients with the outcome of interest. One was a randomized controlled trial and 2 were retrospective cohorts. These articles described both confirmed and possible cases of angioedema. The risk of angioedema was 9.4% (95% confidence interval, 1.6%-17%) for possible cases and 3.5% (95% confidence interval, 0.0%-9.2%) for confirmed cases. No fatal events were reported. No statistical heterogeneity was reported between trials (P > .3). CONCLUSIONS: Limited evidence suggests that for patients who develop angioedema when taking an ACE-I, the risk of development of any subsequent angioedema when taking an ARB is between 2% and 17%; for confirmed angioedema, the risk is 0% to 9.2%. This information will aid clinicians in counseling patients regarding therapy options after development of angioedema due to ACE-Is.

Common variable immune deficiency (CVID) presenting as an autoimmune disease: role of memory B cells.

Common variable immunodeficiency (CVID) is a clinically heterogeneous disorder. Most often patients present with recurrent sinopulmonary infections, although it may present with autoimmune manifestations. Immune cytopenias, particularly thrombocytopenia and hemolytic anemia, are the most commonly observed. While the pathophysiology of CVID remains elusive, in many patients it may be due to an intrinsic B cell defect. Memory B cells (CD27+) in particular, have been noted to correlate with certain aspects of the disease. High numbers of IgM+ memory B cells appear to correlate with the presence of infections, whereas decreased numbers of switched memory B cells correlate with lower serum IgG levels and increased rates of autoimmune features. Because of these defects in the memory B cell compartment, there is a greater potential risk for infection and related complications. Review of the literature suggests that splenectomy should be avoided in patients with immune cytopenia and CVID and that serum immunoglobulins should be obtained in patients presenting with immune cytopenias to screen for CVID.

Absence of erythrocyte sequestration in a case of babesiosis in a splenectomized human patient.

BACKGROUND: The importance of vascular occlusion in the pathogenesis of human haemoprotozoal disease is unresolved. METHODS: Giemsa-stained tissue sections from a human case of Babesia microti infection in a splenectomized patient with chronic lymphocytic leukaemia and colon cancer were examined to ascertain the distribution of parasitized erythrocytes within the vascular lumen. RESULTS: No evidence of sequestration was observed. CONCLUSION: This first report on the vascular location of B. microti in human tissue suggests that severe multi-organ failure due to babesiosis is independent of sequestration of parasitized erythrocytes. A similar pathogenesis may also cause multi-organ failure in other intraerythrocytic protozoal infections, including falciparum malaria.

Progressive pulmonary infiltrates in a patient with ovarian cancer.

We present a case of organizing pneumonia associated with lymphangitic spread of ovarian carcinoma in a 60-year-old Hispanic female with progressive dyspnea, hypoxemia, and bilateral pulmonary infiltrates. The patient was treated with corticosteroids, and she had rapid clinical and radiographic improvement. Malignancy-associated organizing pneumonia has most often been reported in bone-marrow transplant and breast-cancer patients receiving radiation therapy. Data regarding organizing pneumonia in association with other malignancies is quite limited.

Anaphylaxis and epinephrine prescribing patterns in a military hospital: underutilization of the intramuscular route.

Epinephrine is the only definitive treatment of anaphylaxis, and recent evidence suggests that the intramuscular route has superior pharmacokinetics to subcutaneous administration. There is little data regarding what route is commonly used in clinical practice. The objective of this article is to determine the rate of epinephrine use in cases of anaphylaxis and route of administration utilized. A retrospective review was made of 220 medical records with the primary diagnosis of urticaria, angioedema, or anaphylaxis over a 28-month period at a military medical center. Twenty-four cases of anaphylaxis identified in the records. Demographics, along with signs and symptoms of those experiencing anaphylaxis, were similar to other published reports. Epinephrine was given in only 50% of cases and largely by the subcutaneous route. No intramuscular epinephrine was administered. H1 blockers and steroids were the most commonly administered treatments. H2 blockers were given at the same rate as epinephrine. An autoinjector was prescribed in 29% of cases with instruction on its use documented in 13%. An allergy referral was made in 29% of cases. Greater educational efforts and collaboration are needed between the allergy community and other providers regarding the importance of administering epinephrine intramuscularly, prescribing autoinjectors, and referring to an allergist in cases of anaphylaxis.