Cross infection of Haemonchus contortus between calves and lambs.

Haemonchus contortus can frequently be found infecting pre-weaned beef calves on sheep and beef farms around the North Island of New Zealand. The purpose of this study was to determine whether parasites cycling in young cattle constitute a potentially important source of infection for sheep. A field isolate of H. contortus was cycled through either calves or lambs for 3 generations. The larvae resulting from the third cycle of infection were then used to infect both lambs and calves and the resulting faecal nematode egg count (FEC), worm burden, adult worm length and in utero egg count were measured. Larvae derived from lambs inoculated into calves exhibited lower establishment rates, the adult worms were shorter, had lower in utero egg counts, and the resulting faecal egg counts were also lower than when inoculated into lambs (p < 0.01). H. contortus' lack of ability to passage freely between lambs and calves indicates that large populations are unlikely to occur under mixed grazing, resulting in limited potential as a source of infection in sheep. However, indications of an ability to adapt to the alternative host suggest that some investigation of infection in cattle dominant farming operations in the north of the country might be warranted.

Presentation of cutaneous mastocytosis in 173 children.

This is a retrospective review of the case files and clinical photographs of 173 children diagnosed with cutaneous mastocytosis by a dermatologist in an exclusively paediatric practice. Of the 98 males and 75 females, 51% had mastocytomas, 47% had urticaria pigmentosa and three patients had diffuse cutaneous mastocytosis. Of these cases, 87% first appeared prior to or at 6 months of age. Flushing occurred in 26% of urticaria pigmentosa cases, 29% of mastocytomas and 100% of diffuse cutaneous mastocytosis. Blistering was noted in 23% of urticaria pigmentosa, 31% of mastocytomas and 100% of diffuse cases. Neither symptom was noted in 59% of urticaria pigmentosa and 49% of mastocytomas. There were three cases with a positive family history. The finding of a palmar mastocytoma has only once been previously reported. Illustrated descriptions of our cases are provided.

Pachyonychia congenita tarda.

A 42-year-old man presented with painful toenails which were overcurved transversely and onycholytic. Examination revealed that all toenails, the thumbs and index fingers were similarly affected. In addition, he had a small area of leukokeratosis in the mouth, epidermal cysts of the scrotal skin and a small area of hyperkeratosis on the ulnar borders of his hands. His characteristic nail changes began in the great toenails at the age of 20 years. After renal transplantation at age 39, the other nails changed and he developed the features described above. His sister has overcurvature of the fifth toenails. A diagnosis of pachyonychia congenita tarda was made. His case is compared with 14 other reported cases of this rare syndrome.