INTRODUCTION

Mannose-binding lectin (MBL) is an important component of the innate immune system. An association between low levels of MBL and increased susceptibility to infection remains unclear. Alpha-1 antitrypsin deficiency (AATD) patients have been reported to have higher frequency of bronchiectasis [1], and various mechanisms may be involved [2]. To our knowledge no previous studies have looked at the impact of MBL deficiency in a cohort already predisposed to bronchiectasis through AATD.

METHODS

We evaluated a total of 604 patients with AATD participating in a National AATD Registry. We analysed bronchiectasis status with biochemical markers including MBL, IgG and IgE levels, Aspergillus titers and Pseudomonas colonization status in addition to clinical markers such as FEV1% predicted, frequency of exacerbation, mMRC and CAT scores.

RESULTS

A subgroup of AATD patients were identified with MBL deficiency. Preliminary data shows a possible positive association between severe MBL deficiency and severe AATD. Further work will explore correlations with exacerbation frequency, severity of bronchiectasis and patient reported outcomes measures.

CONCLUSION

MBL deficiency may play a role in the pathogenesis of bronchiectasis in AATD, and could be a potential target for treatment.

References:

[1] Chan ED, Wooten W.I., Hsieh E.W.Y., Johnston K.I., Shaffer M., Dandhaus R., van de Veerdonk F. Diagnostic evaluation of bronchiectasis. Respir. Med. X. 2019;1:10006

[2] Sanduzzi A, Ciasullo E, Capitelli L, Sanduzzi Zamparelli S, Bocchino M. Alpha-1-Antitrypsin Deficiency and Bronchiectasis: A Concomitance or a Real Association? Int J Environ Res Public Health. 2020 Mar 29;17(7):2294