O. Tonge 1 , A. Lee2, H.H. Chan3
Leprosy is a granulomatous infection caused by Mycobac- terium leprae. Leprosy primarily affects peripheral nerves and skin, causing tissue destruction and subsequent dis- ability and deformity1. Leprosy is rare in Australia (only 6 cases reported in 2018). Indigenous and immigrant popu- lations bear a disproportionate burden of disease2. Leprosy is classified on a continuum from tuberculoid leprosy (TL) (localised skin lesions with few bacilli and asymmetric nerve involvement) to lepromatous leprosy (LL) (nodular skin lesions with numerous bacilli and symmetric nerve involvement)1.
We describe a case of leprosy at a tertiary hospital. A sys- temically well 62-year-old Cambodian male presented with
4 months of right neck swelling. On examination there were small palpable right upper and posterior cervical and left cervical masses, thought to be enlarged lymph nodes. A PET scan, preformed for suspected malignancy, showed a markedly glucose avid linear abnormality in soft tissues deep to the right tonsillar fossa and what were reported as multiple moderate-markedly glucose avid bilateral lymph nodes. Quantiferon-TB Gold test was positive. Biopsy of the right parapharyngeal space mass showed granulomatous inflammation. Treatment for tuberculous lymphadenitis was commenced. TB PCR on the tissue was negative and subse- quently, Mycobacterium leprae DNA was detected using a panmycobacterial PCR. On further review, the neck masses were in fact enlarged greater auricular nerves and he had pigmented nodules on the right jaw which also had biopsy proven granulomatous inflammation. Tuberculosis treat- ment was ceased, leprosy treatment commenced.
This case highlights the importance of considering leprosy as a differential diagnosis, particularly in atypical presenta- tions.
References
1. Northern Territory Government. Department of Health. Guideli- nes for the control of leprosy in the Northern Territory 2018. Version: 3.0. Updated 28 May 2018. Available at https://digitallib rary.health.nt.gov.au/prodjspui/bitstream/10137/526/3/Control%
20of%20Leprosy%20in%20the%20Northern%20Territory%
20Guidelines.pdf.
2. Australian Government. Department of Health. National Notifi- able Diseases Surveillance System. (2019). Number of notifica- tions of Leprosy, received from State and Territory health authorities in the period of 1991 to 2018 and year-to-date notifi- cations for 2019. Available at http://www9.health.gov.au/cda/ source/rpt_4.cfm.