A new paper alerts clinicians to be on the lookout for symptoms in travellers from countries where the disease is endemic.
A GP has picked up a rare case of leprosy in a 21-year-old Sydney man who migrated to Australia from Nepal about four years ago.
The case is one of 10 that have been confirmed in Australia in the 12 months to 7 August, according to the National Notifiable Diseases Surveillance System’s latest fortnightly report.
This is slightly up in the average of 9.4 notifications per year during the past five years. Traditionally, most locally acquired cases occur in Indigenous Australians who reside in remote communities such as in the Northern Territory and Far North Queensland
The case has been documented in an article in the MJA, and the authors say it highlights the need for vigilance and early diagnosis where possible.
“The reason why we submitted it to the MJA is because we’re getting a lot of international migrants and travellers that are coming to Australia and so I think doctors and allied health stuff need to be aware of what leprosy might look like,” lead author, Dr Akshay Flora told The Medical Republic.
“They [patients] they might have caught it overseas but they only start getting these symptoms and lesions many, many years after they’ve got it. So it might come about once they’ve already moved to Australia.”
Dr Flora, a clinical lecturer in medicine at the University of Sydney with a special interest in dermatology, said there had been several leprosy cases this year that had originated in Nepal.
“I think the message for GPs is that polymorphic rashes or complex rashes definitely should always be referred to the dermatologist,” he said.
“But I think it’s always important to keep in mind differential diagnoses that present with a polymorphic rash, so things like HIV, strongyloidiasis, sarcoidosis, and syphilis, all things that can cause rashes that looks similar to this.
“My other message for GPs is take a good travel history. If a patient’s a migrant, find out where they’re from and whether they have been to places where leprosy is endemic, like Nepal, India or Brazil. That can often be the clue, because we don’t screen for these things.
“When patients come to Australia, we screen for tuberculosis, but we don’t have a good screening test for leprosy, so often that it’s that travel history that will be very important that will provide a key clue to diagnosing leprosy.”
The authors of the MJA case study reported the 21-year-old man had been referred to a Sydney dermatologist with a 12-month history of a polymorphic eruption consisting of widespread macules, plaques, papules, and nodules. As these were asymptomatic, he had not previously sought medical attention.
The patient reported a history of nasal stuffiness, pedal oedema, and malaise. He also noticed numbness in his fingers bilaterally over the previous few months, leading him to scald his hands while working as a kitchen assistant.
“As the patient was from a leprosy endemic region, and had sensory symptoms along with polymorphic lesions, a diagnosis of leprosy was considered,” the authors wrote.
Multiple biopsy samples from his ear, back and foot showed foamy histiocytes throughout the dermis with intracytoplasmic vacuoles, consistent with multibacillary leprosy. Serological investigations and chest x-ray for comorbid conditions and clinical mimics that can present with a polymorphic rash were negative for syphilis, HIV, strongyloidiasis, tuberculosis, and sarcoidosis.
“Due to the high incidence of ocular involvement in leprosy, an eye examination was performed by an ophthalmologist, which was unremarkable,” the authors reported.
“The local public health unit was notified, with close contacts identified and assessed for leprosy. The patient was referred to the infectious diseases department and commenced on a multibacillary leprosy regimen consisting of rifampicin 600mg monthly, clofazimine 300mg monthly and 50mg daily, and dapsone 100mg daily, for at least 12 months.”
Close contacts are defined as anyone who has spent one month living in a “household-like setting”, so Dr Flora said the patient’s work as a kitchenhand was not deemed to be related to close contact issues. Those who fit the criteria with this patient had been identified and tested, he said.
He said the case served as reminder of the importance of early diagnosis and treatment of leprosy, and the fact that it can still occur in Australia.
Leprosy has an average incubation period of five years but it can vary between two and 20 years. Early signs include well defined hypopigmented or erythematous plaques, while late signs include reduced motor power and muscular atrophy, including claw hand deformity, foot drop or facial palsy; thickened earlobes and forehead; loss of eyebrow hair; and nasal septal perforation.
Multidrug treatment is recommended for at least 12 months, and includes rifampicin, clofazimine, and dapsone. These medications are provided for free to patients in Australia. Regular follow-up is required up to five years after treatment completion.
Dr Flora told TMR that while GPs could diagnose the disease, treatment required a multidisciplinary approach that included infectious diseases specialists, dermatologists, ophthalmologists and neurology specialists where required.
“I think the key message for leprosy for both GPs and dermatologists is the fact that timely treatment can prevent this from worsening, because once you do get those neurological signs and symptoms, they usually can’t be reversed,” he said.
