Importance of Aspergillus-Specific Antibody Screening for Diagnosis of Chronic Pulmonary Aspergillosis after Tuberculosis Treatment: A Prospective Follow-Up Study in Ghana

Abstract

Chronic pulmonary aspergillosis (CPA) often occurs in patients that have been previously treated for pulmonary tuberculosis (PTB). A limited number of studies have looked at the development of CPA at different times following the completion of a PTB treatment course. This prospective longitudinal study aimed to determine the incidence of CPA at two timepoints, at the end of the PTB treatment (T₁) and six months post-treatment (T₂). Patients with confirmed PTB from a previous study who were placed on anti-TB medication were followed up and screened for CPA at T₁ and T₂ by assessing their symptoms, evaluating their quality of life, and screening them for Aspergillus infection by performing antibody testing and cultures. CPA was defined by the Global Action for Fungal Infections (GAFFI) diagnostic algorithm. Forty-one patients were enrolled, of whom thirty-three patients (80%) and twenty-eight patients (68%) were resurveyed at T₁ and T_2, respectively. The rate of new CPA was 3.3% (1/33) and 7.4% (2/27) at T₁ and T₂, respectively, with an overall incidence of 10.7% (3/28) among the patients at both T₁ and T₂. A positive Aspergillus-specific antibody test was an indicator for CPA in all three patients. Aspergillus-specific antibody screening during and after the end of an anti-TB treatment regimen may be important for early detection of CPA in high-PTB-burden settings.

Keywords: Aspergillus antibody; Ghana; chronic pulmonary aspergillosis; tuberculosis.

Figure 1

Overview of 41 patients enrolled.

Figure 2

Axial non contrast CT scan, coronal reformatted lung, and axial mediastinal windows of the chest of the patient diagnosed with CPA at T₁ (A). Extensive left lung traction bronchiectasis (blue arrows) with ipsilateral lung volume loss, left apical lung cavity with intracavitary material (yellow arrow); (B) left apical lung pericavitary pleural thickening (red arrow).

Figure 3

Axial contrast CT scans, axial lung window of chest of another CPA patient diagnosed at T₂ showing (A) a soft tissue mass within a left apical lung cavity (blue arrow) with a characteristic crescent of air around it, the ‘Monod sign’, indicative of an aspergilloma. (B). Nodular opacities (red arrow) and non pericavitary fibrotic changes in the left upper lobe.

Figure 4

Axial non contrast CT scan, axial mediastinal and lung windows of the chest of the third CPA patient diagnosed at T₃ patient, demonstrating (A) right lung nodules (blue arrow); (B) small right lower lobe cavity with pericavitary infiltration (red arrow) as well as a small pleural effusion (yellow arrow).