# Aspergillus Serology Predicts Relapse in Chronic Pulmonary Aspergillosis: Implications for Personalised Follow‐Up Strategies

## TL;DR

This study shows that blood tests for Aspergillus can predict if patients with lung aspergillosis will relapse after treatment, suggesting personalized follow-up strategies.

## Contribution

The study identifies Aspergillus-specific IgE and IgG as novel predictors of relapse in chronic pulmonary aspergillosis.

## Key findings

- Aspergillus sensitization and elevated IgG levels were independently linked to relapse.
- No relapses occurred in patients with IgG levels below 40 mg/L.
- Underlying lung disease or treatment duration did not predict relapse.

## Abstract

Relapses occur in up to 40% of patients after prolonged courses of antifungal treatment for chronic pulmonary aspergillosis (CPA). The factors predisposing to relapse remain poorly defined.

We conducted a retrospective study of adults treated for ≥ 6 months with oral azoles for CPA. Patients who completed antifungal therapy and were deemed not to require further treatment were included. Demographic, clinical, radiological and serological data at treatment completion were collected. CPA relapse was defined as symptomatic and radiological deterioration leading to re‐initiation of antifungal therapy. Cox regression and Kaplan–Meier analyses were used to identify predictors of relapse and mortality.

Among 125 patients (56% male; mean age 61 years), median treatment duration was 36 months. Thirty‐two (26%) developed relapse; relapse rate at 1 year was 16%. Aspergillus sensitisation (specific IgE > 0.35 IU/mL) and elevated Aspergillus‐specific IgG (> 40 mg/L) at treatment completion were independently associated with relapse (p < 0.05). No patient with IgG < 40 mg/L relapsed. Underlying lung disease (COPD or prior tuberculosis), extent of radiological involvement, or treatment duration were not significantly associated with relapse or mortality.

Aspergillus sensitisation and persistently elevated Aspergillus‐specific IgG at the end of antifungal therapy were independent predictors of CPA relapse. These parameters may reflect ongoing fungal airway burden and can help identify patients requiring extended or closer post‐treatment follow‐up. Underlying comorbidities were not associated with relapse risk.