Density-based MDCT quantification of lobar lung volumes: a study of inter- and intraobserver reproducibility.

PURPOSE: The authors assessed the reproducibility of multidetector-row computed tomography (MDCT) volumetry of the total and emphysematous parenchyma of pulmonary lobes. MATERIALS AND METHODS: Two observers analyzed 23 MDCT examinations of patients with emphysema during two sessions held 3 months apart. Both lungs and all lobes were delimited by a combination of semiautomated and manual segmentation. Emphysematous parenchyma was obtained by applying density thresholds of -1,024/-950 HU. To assess the reproducibility of total volume (V), volume of emphysema (VE) and emphysema index (EI), intra- and interobserver differences of those measurements were assessed. RESULTS: Total volumetry of the lungs was highly reproducible (intra- and interobserver variability of +/-3.4%). Variability between measurements was slightly greater or emphysema volume and index (EI). Lobar analyses showed large ranges of intra- and interobserver variability (intraobserver V=+/-3.7%-10.6%; VE=+/-17.3%-32.9%; EI=+/-17.8%-34%; interobserver V=+/-13.3%-98.3%; VE=+/-11%-137.6%; EI=+/-28.9%-96.4%). CONCLUSIONS: MDCT quantification of total and emphysematous lung volume and emphysema index is overall reproducible. Quantitative assessment of those parameters performed on single lobes is affected by variability. An improvement of the reproducibility of q-MDCT is expected from the use of advanced methods for lobar segmentation.

Assessment of renal function in patients with multiple myeloma: the role of urinary proteins.

Renal failure (RF) in multiple myeloma (MM) is considered an ominous complication even though, when timely therapy is started in patients with minimal damage, a high percentage of cases can achieve a regression. The evaluation of renal involvement usually relies on serum creatinine or its clearance, but these parameters have proved to be inadequate to identify initial damage. The aim of this study was to assess the role of the following urinary proteins in diagnosing renal impairment at an early stage: high-molecular-mass proteins (transferrin, IgG, albumin) as markers of glomerular damage, and low-molecular-weight proteins and parenchymal enzymes [alpha(1)-acid glycoprotein (AGP), alpha(1)-microglobulin (alpha(1)M), retinol-binding protein (RBP), beta(2)-microglobulin (beta(2)M), lysozyme (LZ), and N-acetyl-beta-d-glucosaminidase (NAG)] as indicators of tubular disorder. Thirty MM patients (nine at disease onset and 21 previously treated) were included in the study. No correlation was found between the urinary proteins and the phase or the stage of the disease. By the Spearman test, Bence Jones proteinuria correlated significantly with the 24 h proteinuria (p=0. 01) and beta(2)M (p=0.02), and weakly with the alpha(1)M. Serum creatinine concentrations and urea correlated with most of the analytes evaluated: RBP correlated well with urea (p=0.004) and creatinine (p=0.004); IgG (p=0.006) albumin (p=0.009), AGP (p=0.04), and NAG (p=0.02) correlated with serum creatinine. Significant statistical correlation was found between all the analytes except LZ and the creatinine clearance. Twelve of the 30 MM patients (40%) showed abnormal values of urinary proteins. Four of these patients showed overt renal failure with significant modification of the serum parameters and of creatinine clearance, three showed an isolated decrease of creatinine clearance, and five did not present any alteration of serum or urinary parameters. This testifies to the utility of urinary proteins in highlighting renal damage even in cases where the customary serum indicators of renal disorder are normal. In conclusion, our results demonstrate that AGP, RBP, NAG, transferrin, and IgG are good indicators of renal damage. They do not correlate with the severity of the disease, but they seem to be helpful in identifying a subset of patients with initial renal dysfunction.

Hyperamylasemia due to macroamylasemia in adult gluten enteropathy.

We report hyperamylasemia due to macroamylasemia in a 33-year-old-woman with gluten enteropathy. Macroamylasemia was demonstrated by precipitation of 97% of amylase activity with PEG 6000. It was associated with increased serum IgA, with elevated values of specific IgA antibodies against alpha-gliadin and with a high titre of IgA anti-endomysium antibodies. Macroamylasemia disappeared after 2 months of a strict gluten-free diet. These data suggest that the increased IgA concentration in adult gluten enteropathy led to increased macroamylase formation.