Common presentation: Rare disease: Adult Langerhans cell histiocytosis.

A 19-year-old boy presented with signs of a granulomatous lung disease. Sputum testing for tuberculosis was negative. After a year, he returned with generalised lymphadenopathy. Though a clinical diagnosis of tuberculosis was then made and treatment was commenced, a lymph node biopsy revealed Langerhans cell histiocytosis. We are not aware of any other such case described in the Pacific.

Simple leg ulcers: difficult diagnosis.

Chronic leg ulcers in children in tropical developing countries are common. They are difficult to diagnose clinically and to manage. Our case illustrates that even in areas where yaws is endemic and point of care testing is available, the diagnosis remains difficult.

Tropical leg ulcers in children: more than yaws.

The management of yaws has changed in recent years. Mass treatment with oral azithromycin has replaced intramuscular benzathine benzylpenicillin. Treponemal and non-treponemal serology (equivalent to TPHA and RPR) point-of-care blood testing is now available. In addition, recent studies in yaws endemic regions have shown that a significant number of leg ulcers in children which are clinically suggestive of yaws are caused by Haemophilus ducreyi. It is noteworthy that the World Health Organization has also set the ambitious goal to eliminate yaws by 2020.

Molecular differentiation of Treponema pallidum subspecies in skin ulceration clinically suspected as yaws in Vanuatu using real-time multiplex PCR and serological methods.

We developed a TaqMan-based real-time quadriplex polymerase chain reaction (PCR) to simultaneously detect Treponema pallidum subspecies pallidum, T. pallidum subsp. pertenue, and T. pallidum subsp. endemicum, the causative agents of venereal syphilis, yaws, and bejel, respectively. The PCR assay was applied to samples from skin ulcerations of clinically presumptive yaws cases among children on Tanna Island, Vanuatu. Another real-time triplex PCR was used to screen for the point mutations in the 23S rRNA genes that have previously been associated with azithromycin resistance in T. pallidum subsp. pallidum strains. Seropositivity by the classical syphilis serological tests was 35.5% among children with skin ulcerations clinically suspected with yaws, whereas the presence of T. pallidum subsp. pertenue DNA was only found in lesions from 15.5% of children. No evidence of T. pallidum subsp. pertenue infection, by either PCR or serology was found in ∼59% of cases indicating alternative causes of yaws-like lesions in this endemic area.

Challenges and key research questions for yaws eradication.

Yaws is endemic in west Africa, southeast Asia, and the Pacific region. To eradicate yaws by 2020, WHO has launched a campaign of mass treatment with azithromycin. Progress has been made towards achievement of this ambitious goal, including the validation of point-of-care and molecular diagnostic tests and piloting of the strategy in several countries, including Ghana, Vanuatu, and Papua New Guinea. Gaps in knowledge need to be addressed to allow refinement of the eradication strategy. Studies exploring determinants of the spatial distribution of yaws are needed to help with the completion of baseline mapping. The finding that Haemophilus ducreyi causes lesions similar to yaws is particularly important and further work is needed to assess the effect of azithromycin on these lesions. The integration of diagnostic tests into different stages of the eradication campaign needs investigation. Finally, studies must be done to inform the optimum mass-treatment strategy for sustainable interruption of transmission.

SLE and dental erosion: a lethal cocktail.

A 13-year-old Pacific Island girl presented complaining of fever, joint pain and dry mouth. She was using limes to relieve her dry mouth. On examination, the most striking clinical finding was severe dental erosion and caries. Autoimmune serology confirmed a diagnosis of systemic lupus erythematosus (SLE) with possible Sjögren's syndrome. The case illustrates the devastating consequence of excessive consumption of acidic citrus juice in sicca syndrome.

Resurgence of yaws in Tanna, Vanuatu: time for a new approach?

Recent reports from the island of Tanna in Vanuatu suggest that yaws has resurged. We carried out a serological and clinical survey to determine the prevalence and clinical presentation of yaws on the island. A total of 306 random serum samples were tested for rapid plasma reagin and rapid diagnostic determine syphilis: 31.04% were positive for one or both tests; 39.8% of children surveyed in three schools had skin lesions consistent with yaws; and there were only two cases of secondary yaws osteitis and no cases of tertiary yaws. These results confirm that the disease has resurged but appears to be attenuated. Intramuscular benzathine penicillin is the currently recommended treatment for yaws. We suggest that a stat dose of oral azithromycin would be a more accessible treatment as it could be prescribed by village health workers and therefore enable yaws control to be more easily incorporated into other primary health-care programmes.