Approach to the evaluation of adverse antibiotic reactions in patients with cystic fibrosis.

BACKGROUND: Adverse drug reactions (ADRs) to antibiotics in patients with cystic fibrosis (CF) are common and often mislabeled as allergies. The labeling of an antibiotic reaction as an allergy can lead to the use of antibiotics that are less efficacious, are more expensive, or have a greater risk of adverse effects. OBJECTIVE: To establish a safe approach for the evaluation of ADRs to antibiotics in patients with CF to help clarify future use of these medications. METHODS: Patients with CF whose antibiotic allergies were causing difficulty in their medical management were referred for an allergy evaluation that consisted of a thorough drug allergy history and antibiotic testing if appropriate. If the history was not consistent with a true hypersensitivity reaction (HSR) and test results were negative, the patient underwent a challenge to the offending agent(s) to rule out an HSR. Challenges were only performed if the medication was indicated for future use. RESULTS: A total of 17 patients (mean age, 32.4 years) underwent a thorough allergy evaluation. A total of 17 antibiotic challenges were performed in 11 patients without a reaction consistent with an HSR or severe delayed reaction. Only 2 medications had a history consist with an HSR, and it was recommended that they undergo a desensitization procedure if the drug was required. CONCLUSION: If treatment with appropriate antibiotics becomes difficult in patients with CF because of drug allergies, then referral to an allergist can help safely identify treatment options. Our findings suggest that a thorough evaluation by an allergy specialist can lead to more appropriate treatment options in patients with CF.

Polyarteritis nodosa-like vasculitis in association with minocycline use: a single-center case series.

OBJECTIVE: To describe the clinical features, treatment, and outcomes of polyarteritis nodosa (PAN)-like vasculitis in association with minocycline therapy. METHODS: We identified all subjects ≥18 years old with PAN-like vasculitis in the context of minocycline use seen at our institution between January 1995 and October 2010. Cases of hepatitis B-associated PAN were excluded. PAN was defined based on angiographic findings or tissue biopsy. Minocycline use was defined as medication use at the time of onset of first symptom. RESULTS: We identified 9 patients (5 females; 56%) with a median age of 30 (range 18 to 55) years. Four patients (44%) had isolated cutaneous disease, while 5 cases (56%) had systemic involvement including renal artery microaneurysms (2 patients), cholecystitis (1 patient), mononeuritis multiplex (2 patients), and mesenteric vasculitis (1 patient). Median duration of minocycline use was 2 (range 1 to 4) years. Three patients had a positive antinuclear antibody with negative extractable nuclear antigen antibodies. All patients had positive antineutrophil cytoplasmic antibody in a perinuclear pattern but specificity to myeloperoxidase was observed in 2 patients (22%). Diagnosis was confirmed by histopathology in 6 patients (67%) and angiography in 3 patients (33%). Minocycline was discontinued in all cases. Further immunosuppressive therapy was added in 6 cases (67%). CONCLUSIONS: Cutaneous, as well as systemic, PAN-like vasculitis may occur in association with minocycline use. Clinicians should consider the possibility of drug-induced vasculitis, especially in cases of medium-vessel vasculitis with atypical antineutrophil cytoplasmic antibody serologies or in patients with negative hepatitis B testing.

Atypical Omenn Syndrome due to Adenosine Deaminase Deficiency.

We present here a novel case of an atypical Omenn syndrome (OS) phenotype due to mutations in the ADA gene encoding adenosine deaminase. This case is noteworthy for a significant increase in circulating CD56(bright)CD16- cytokine-producing NK cells after treatment with steroids for skin rash.