Nontuberculous mycobacteria otomastoiditis with facial palsy.

Abstract

A 5-year-old male patient, receiving bilateral ventilation tube insertions 8 months ago, suffered from persisting left otorrhea and hearing loss for 3 months recently, accompanied by left post-auricular mass for 2 weeks. The examination revealed a grade IV left peripheral facial palsy (House-Brackmann grading system). High-resolution computed tomography (HRCT) (Fig. 1A and supplementary video) demonstrated opacification of the left tympanic cavity, epitympanum, mastoid antrum, and air cells. Bony erosion of the tympanic segment of the facial nerve was noticed. In contrast, HRCT demonstrated normal right external auditory canal structures and middle ear with normal pneumatization (Fig. 1B). Contrast-enhanced axial CT (Fig. 2) showed a 4-cm peripheral enhanced subperiosteal postaural abscess. He had poor empirical antibiotic therapy and topical treatment response. Left mastoidectomy was performed. Furthermore, microscopic examination of tissue samples found granulomas. Smears detected no acid-fast bacillus (AFB). Three weeks later, tissue culture was proven as Mycobacteria abscessus complex. Facial palsy improved significantly after surgical intervention as the facial nerve was relieved from inflammation and edema. The patient was treated with antimycobacterial agents for 9 months. However, his left eardrum remained perforated.Figure 2Contrast-enhanced axial computed tomography revealed a peripheral enhanced abscess over the postauricular area (arrowhead). The heterogeneously enhanced middle ear and external auditory canal soft tissue density were detected (arrow).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Nontuberculous mycobacteria (NTM) otomastoiditis was first described in 1976.1Austin W.K. Lockey M.W. Mycobacterium fortuitum mastoiditis.Arch Otolaryngol. 1976; 102: 558-560Crossref PubMed Scopus (29) Google Scholar NTM otomastoiditis is a rare type of extrapulmonary NTM that mostly affects children and may present with nonspecific symptoms, including persisting painless otorrhea, tympanic membrane perforation, middle ear granulation, and hearing loss. The incidence of facial nerve weakness in NTM otomastoiditis was approximately 12%, much higher compared to typical bacterial otomastoiditis.2Lundman L. Edvardsson H. Ängeby K. Otomastoiditis caused by non-tuberculous mycobacteria: report of 16 cases, 3 with infection intracranially.J Laryngol Otol. 2015; 129: 644-655Crossref PubMed Scopus (9) Google Scholar Facial nerve weakness in NTM otomastoiditis was mostly transient. Eardrum defect with either ventilation tube or perforation is a major risk factor for NTM otomastoiditis in children. Previous reports showed that approximately 90% of the children had a history of ventilation tubes or eardrum perforations.2Lundman L. Edvardsson H. Ängeby K. Otomastoiditis caused by non-tuberculous mycobacteria: report of 16 cases, 3 with infection intracranially.J Laryngol Otol. 2015; 129: 644-655Crossref PubMed Scopus (9) Google Scholar Differentiation between NTM and tuberculosis (TB) infection can be difficult. Clinical findings of NTM and TB otomastoiditis often overlap, causing diagnostic difficulties.3Doan H.T.H. Hoang P.T. Tran T.P.C. Tuberculous otitis media in Vietnam: clinical features and diagnostic difficulties.Eur Ann Otorhinolaryngol Head Neck Dis. 2021; 138: 467-469Crossref Scopus (2) Google Scholar AFB staining would identify mycobacteria; however, it does not discriminate NTM from TB. Hence, the growth and identification of NTM from the clinical specimens are necessary. The culture of mycobacteria is the gold standard for NTM infection diagnoses.4Gopalaswamy R. Shanmugam S. Mondal R. Subbian S. Of tuberculosis and non-tuberculous mycobacterial infections - a comparative analysis of epidemiology, diagnosis and treatment.J Biomed Sci. 2020; 27: 74Crossref PubMed Scopus (56) Google Scholar Culture is the first step in species identification. It evaluates clinical significance and antimicrobial resistance. Other diagnostic modalities can be applied only after identifying the growth of the culture media. If patients with NTM otomastoiditis did not respond to antibiotics, they could further receive mastoidectomy to reduce local bacterial load.2Lundman L. Edvardsson H. Ängeby K. Otomastoiditis caused by non-tuberculous mycobacteria: report of 16 cases, 3 with infection intracranially.J Laryngol Otol. 2015; 129: 644-655Crossref PubMed Scopus (9) Google Scholar HRCT is the image of choice to evaluate temporal bone structures. The middle ear and mastoid cavity opacification with possible fluid levels are found on HRCT. Moreover, trabeculae and cortical bone destruction can be occasionally noted in coalescent mastoiditis. If the disease inflammatory process continues, subsequent lateral mastoid cortex penetration would result in subperiosteal abscess formation. Chronic epithelial infection may result in basement membrane disruption; hence, the formation of granulation tissue. The soft tissue expanding facial nerve, with or without surrounding bony destruction, may occasionally be noticed in cases with facial palsy.5Ho M.L. Juliano A. Eisenberg R.L. Moonis G. Anatomy and pathology of the facial nerve.AJR Am J Roentgenol. 2015; 204: W612-W619Crossref PubMed Scopus (21) Google Scholar The radiological differential diagnoses of NTM otomastoiditis should include other infectious processes, cholesteatoma, cholesterol granuloma, and Langerhans’ cell histiocytosis in children.6Lo A.C.C. Nemec S.F. Opacification of the middle ear and mastoid: imaging findings and clues to differential diagnosis.Clin Radiol. 2015; 70: e1-e13Abstract Full Text Full Text PDF PubMed Scopus (10) Google Scholar Possibilities of NTM otomastoiditis should always be considered in patients presenting with facial palsy with extensive disease and poor treatment response for common bacterial otomastoiditis. The authors declare no conflict of interest. The following is the Supplementary data to this article.eyJraWQiOiI4ZjUxYWNhY2IzYjhiNjNlNzFlYmIzYWFmYTU5NmZmYyIsImFsZyI6IlJTMjU2In0.eyJzdWIiOiJjYWM5YjE1YmNmMWUzMGNhODlmZWQ4OGFjYTYzOTcyNyIsImtpZCI6IjhmNTFhY2FjYjNiOGI2M2U3MWViYjNhYWZhNTk2ZmZjIiwiZXhwIjoxNjc2MTQ2OTI5fQ.kDovTztnzM-zDpwRPhetcuw6Ou0My3ZN3nYX2SMt5PwUcfL7L9cbyhBznzHBs7n0p__GI7Zbh-golLjGr1jtPpXFLj-K2VUsGr3OYtMO4omqKBjwd2FTod6cad11owP647_j857HCXtEwpZzHy3PL2IAYxzSNYsogLPh1AxyIuJCwNk8zvzEHYOrkuiVtVxd9L2LaTRcGT8tYF-q5801fpRLq9VF7XETFH7uS5oAVMV9bvs8IXWIRDT5gYM2cxvILyl6Dy3aIhofv83wzwYsdW701QdGXU6b_KXobjrFllVqFUd5Rk3q8Jfu29vQcy8KzMfwXfciME-43LCiEUSY-Q Download .mp4 (1.4 MB) Help with .mp4 files Supplementary VideoAxial and coronal high-resolution computed tomography with the blue and yellow arrows tracing the course of the left facial nerve, showing bony erosion of the tympanic segment of the facial nerve.