Discussion
Actinomyces species were first identified in Israel during 1878 from human necropsy tissue. [6] Ponfick reported the first case of thoracic actinomycosis in 1882. [7]
Several species of Actinomyces have been identified in humans with at least 21 species identified with the use of 16S rRNA sequencing. [8] Actinomyces israelii remains the predominant species causing cervicofacial, abdominopelvic, and thoracic actinomycosis.
Diagnosis of paediatric pulmonary actinomycosis remains a challenge because it is a rare disease (even in resource limited settings) with no specific features on imaging. CT findings that have been described include airspace consolidation, lobar consolidation, ground glass opacification, pleural effusions, pleural thickening, hilar lymphadenopathy and a necrotic mass. [9] Both the CXR and CT-scan findings may mimic TB, which can lead to misdiagnosis in settings with a high TB burden. In addition to the diagnostic difficulties, this patient experienced a delay in referral for nearly a year due to the SARS-CoV-2 pandemic. Diagnosis was further delayed due to limited chest x-rays during the pandemic.
In cases of endobronchial involvement, a follow-up bronchoscopy is essential after treatment has started and imaging has shown improvement in order to exclude a foreign body. Foreign body-induced endobronchial actinomycosis have been reported in 45% of adult cases and in most cases the foreign body was detected only after starting antibiotic therapy. In these cases, the foreign body should always be removed. [10]
Patients with thoracic actinomycosis may be candidates for individualized courses of therapy depending on the initial burden of disease, whether resection surgery was performed, and the clinical and radiologic responses to therapy. The traditional recommendation of IV antibiotic therapy for 2 to 6 weeks followed by oral antibiotic therapy for 6 to 12 months is not always necessary. [11]