Pulsed dye laser treatment of capillary malformations in infants at 2-weekly versus 3-monthly intervals, reducing the need for general anaesthesia.

Capillary malformations (CM) cause significant psychosocial complications. Pulsed dye laser (PDL) treatment at 6-12-weekly intervals under general anaesthesia (GA) commencing in infants at 6 months of age remains the standard of care in order to achieve maximal improvement prior to school age. The safety of repeated GA in children is controversial.

Mohs' micrographic surgery as treatment for squamous dysplasia of the nail unit.

We report a series of 14 cases of nail unit squamous cell carcinoma in situ/ Bowen's disease and squamous cell carcinoma (SCC) treated with Mohs micrographic surgery (MMS). MMS has been previously reported as an ideal treatment for nail unit SCC. This series adds to the current literature substantiating this claim, and also demonstrates the good outcomes achieved with secondary intention healing.

Childhood and adolescent orofacial granulomatosis is strongly associated with Crohn's disease and responds to intralesional corticosteroids.

We present seven cases of orofacial granulomatosis occurring in paediatric patients aged 6-16 years. All patients were investigated for Crohn's disease and a strong association was found. All patients were treated with intralesional corticosteroid injections with excellent clinical responses.

Solitary mastocytoma occurring at a site of trauma.

We describe a patient with a solitary mastocytoma arising at a site of trauma. The patient was born with the umbilical cord wrapped around her right thigh and subsequently developed a solitary mastocytoma in the exact site and distribution of this injury. The pathogenesis of mast cell proliferation in solitary mastocytoma is not completely understood.

The Rac2 guanosine triphosphatase regulates B lymphocyte antigen receptor responses and chemotaxis and is required for establishment of B-1a and marginal zone B lymphocytes.

We have defined roles for the hemopoietic-specific Rho guanosine triphosphatase, Rac2, in B lymphocyte development and function through examination of rac2(-/-) mice. Rac2-deficient mice displayed peripheral blood B lymphocytosis and marked reductions in peritoneal cavity B-1a lymphocytes, marginal zone B lymphocytes, and IgM-secreting plasma cells as well as reduced concentrations of serum IgM and IgA. The rac2(-/-) B lymphocytes exhibited reduced calcium flux following coligation of B cell AgR and CD19 and reduced chemotaxis in chemokine gradients.