Correlation of airway hyper-responsiveness with obstructive spirometric indices and FEV(1) > 90% of predicted.

BACKGROUND: Current published guidelines on spirometry interpretation suggest an elevated FVC and FEV(1) > 100% of predicted with an obstructive ratio may represent a physiological variant. There is minimal evidence whether this finding can be indicative of symptomatic airways obstruction. METHODS: Pulmonary function testing databases for a 4-year period were retrospectively reviewed. All technically adequate spirometry studies were included, based on these criteria: FEV(1) > 90% of predicted, and FEV(1)/FVC below the lower limit of normal, based on 95th percentile confidence intervals. Clinical indications for testing were noted. Testing for post-bronchodilator response, lung volumes, and methacholine challenge tests were reviewed for evidence of airway hyper-responsiveness (AHR). Comparisons were made between symptomatic versus asymptomatic individuals and FEV(1) values less than or greater than 100% of predicted. RESULTS: A total of 280 studies were analyzed. During their clinical evaluation, 192 patients (69%) had post-bronchodilator spirometry recorded, 63 patients (23%) had lung volumes, and 36 patients (11%) completed methacholine challenge testing. Indications for spirometry included 193 symptomatic patients and 87 asymptomatic patients. Nearly 28% of patients with post-bronchodilator testing met criteria for AHR. No differences in AHR were found between the symptomatic and asymptomatic groups. The majority of patients (77%) with AHR had an FEV(1) < 100%, when compared to patients with an FEV(1) ≥ 100%. CONCLUSIONS: A normal FEV(1) > 90% of predicted with obstructive indices may not represent a normal physiological variant, as 28% of patients were found to have underlying AHR. These findings suggest that clinicians should evaluate for AHR, especially in symptomatic patients, even if the FEV(1) is > 90% of predicted.

Severe serum sickness reaction to oral and intramuscular penicillin.

Serum sickness is a type III hypersensitivity reaction mediated by immune complex deposition with subsequent complement activation, small-vessel vasculitis, and tissue inflammation. Although the overall incidence of serum sickness is declining because of decreased use of heterologous sera and improved vaccinations, rare sporadic cases of serum sickness from nonprotein drugs such as penicillins continue to occur. Drug-induced serum sickness is usually self-limited, with symptoms lasting only 1-2 weeks before resolving. We report an unusual case of a severe and prolonged serum sickness reaction that occurred after exposure to an intramuscular penicillin depot injection (probable relationship by Naranjo score) and discuss how pharmacokinetics may have played a role. Clinicians should be familiar with serum sickness reactions particularly as they relate to long-acting penicillin preparations. Accurate diagnosis in conjunction with cessation of drug exposure and prompt initiation of antiinflammatory treatment with corticosteroids can produce complete recovery