Of oranges and lemons: you are what you eat.

A young boy presented with increasing lower limb pain and swelling for a month. At the time of his hospitalisation, he was unable to walk. We report the patient's clinical journey with clinical commentary throughout, highlighting the importance that uncommon diseases may be diagnosed with a high index of suspicion and thorough history taking.

CAPS: a rare acute abdomen.

An 11-year-old girl presented to the hospital with vomiting, left upper-quadrant pain and blood in the stool. An ultrasound scan showed no blood flow in the coeliac axis or the splenic artery. A contrast-enhanced CT scan then demonstrated no flow beyond the coeliac axis origin, a large clot in the distal superior mesenteric artery (SMA), a large splenic infarct and bilateral renal infarcts. Investigations revealed a positive lupus anticoagulant and she was given a presumptive diagnosis of catastrophic antiphospholipid syndrome (CAPS). She was anticoagulated and started on combination immunosuppressive therapy. Her surgical management was by SMA embolectomy, small bowel resection and proximal stoma formation. Stoma closure was performed at 3 months, and she was eventually established on full enteral feeds. Childhood CAPS is a rare condition with a very high mortality rate, and the successful outcome in this case reflects close multidisciplinary teamwork between medical and surgical specialties.

Extreme hyponatraemia with intact neurological outcome in a young child with Addison's disease.

The authors present the case of a 6-year-old boy with a good neurological outcome from extreme hyponatraemia caused by autoimmune hypoadrenalism. He presented with 1 week of reduced appetite, lethargy, vomiting and one episode of diarrhoea. He was described as being slightly unsteady on his feet. Clinically he was alert, although intermittently confused, with dry mucous membranes and sunken eyes. Serum sodium was 96 mmol/l with normal serum potassium and renal function. He was initially treated with 3% saline intravenously, and his serum sodium increased to 128 mmol/l by day 3. He developed slurred speech and ataxia on day 4, although MRI brain showed no evidence of pontine myelinosis, and the symptoms resolved over 1 week. A Synacthen test on day 10 confirmed a diagnosis of Addison's disease and he was commenced on hydrocortisone and fludrocortisone replacement therapy. At 5 months follow-up there are no obvious neurological or developmental sequelae.