Comparison of serum markers for allergic bronchopulmonary aspergillosis in cystic fibrosis

¹ Division of Respiratory Medicine, Children's University Hospital of Berne, Switzerland; and Children's Hospital of the Ludwig-Maximilians-University of Munich, Germany
² Children's Hospital of the Ludwig-Maximilians-University of Munich, Germany
³ Division of Respiratory Medicine, Children's University Hospital of Berne, Switzerland

^* To whom correspondence should be addressed. E-mail: philipp.latzin{at}insel.ch.

	Abstract

The diagnosis of allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis (CF) is a challenge. Thymus- and activation-regulated chemokine (TARC) has recently been reported to play a role in ABPA. We aimed to compare the diagnostic value of TARC with known serological markers for diagnosis of ABPA in CF patients.

We followed longitudinally 48 CF patients, of whom 12 had a diagnosis of ABPA according to Nelson's criteria, for one to eight years with repeated measurements of serum total IgE, specific Aspergillus fumigatus IgE and IgG, recombinant Aspergillus fumigatus allergens f1, f3, f4 and f6 and TARC.

Median (IQR) TARC levels were 589 (465–673) pg·ml^-1 in ABPA patients and 232 (189–289) pg·ml^-1 in non-ABPA patients. Receiver operating characteristic (ROC) curves revealed that TARC was superior to the other markers for diagnosis of ABPA. The sensitivity, specificity and diagnostic accuracy were higher for TARC (92%, 95% and 93%) than for total IgE (65%, 81% and 74%), rAsp f4 (82%, 71% and 75%) or f6 (65%, 87% and 79%).

Our study indicates that TARC may be useful for the diagnosis of ABPA in CF patients. However, larger studies are needed before TARC can routinely be used in diagnostic algorithms.