Acute necrotizing encephalopathy in a child with H1N1 influenza infection.

Since the World Health Organization declared a global pandemic of novel influenza A H1N1 in June 2009, there has been a sustained rise in the number of cases of this strain of influenza. Although most cases are mild with complete and uneventful recovery, multiple cases of severe infection with complications including death have been reported. To the best of our knowledge, the majority of fatal outcomes in the United States have been related to pulmonary complications. We report a 12-year-old girl infected with influenza A H1N1 whose clinical course was complicated by rapid progressive neurologic deterioration and striking CT and MRI findings consistent with acute necrotizing encephalopathy (ANE). To our knowledge this has not been reported in the pediatric radiology literature. We hope this case will alert radiologists to this complication and familiarize radiologists with imaging findings that herald ANE.

A congenital foregut malformation with a laryngeal bronchus.

We present the case of a 2-month-old boy who required intubation at birth for stridor, at which point a supraglottic cyst was noted. With recurrence of the cyst, a subsequent computed tomographic scan and magnetic resonance imaging demonstrated a mass encroaching on the larynx, descending into the mediastinum, and encasing the major vessels. A median sternotomy and transcervical incision enabled excision of a well-defined mass with a laryngeal attachment. This attachment was consistent with a bronchus on histopathologic investigation. To our knowledge, this is the first reported case of ectopic lung tissue arising from the larynx and descending into the mediastinum.

Significant and persistent loss of bone mineral density in the femoral neck after haematopoietic stem cell transplantation: long-term follow-up of a prospective study.

Reduced bone mineral density (BMD) has been reported following allogeneic stem cell transplantation (alloSCT) but the effects of autologous SCT (autoSCT) are less well characterized. We performed a prospective study of BMD changes and its determinants in 44 SCT recipients (38 auto and six allo; 30 peripheral blood SCT and 14 bone marrow transplantation). Serial measurements of BMD at the lumbar spine and femoral neck were performed at baseline and at 3, 6, 12 and 24 months, and spinal radiographs were performed at baseline and 12 months. Mean baseline BMD values at the femoral neck and spine were within normal limits. At 3 months, there was a significant decline of BMD at the femoral neck (P = 0.011) and a non-significant trend towards reduction at the spine. BMD loss persisted for up to 2 years at the femoral neck (P = 0.005), but values returned to baseline at the spine. Reflecting the rapid initial decline in BMD, bone-specific alkaline phosphatase (a serum marker of bone formation) showed a significant initial decline at 1 month but had recovered to pretransplant levels by 3 months. No new fractures were detected at 1 year post transplant. Sex, diagnosis, use of total body irradiation, stem cell source and type of graft (auto versus allo) did not significantly predict BMD change over the first 12 months. In conclusion, significant and persistent bone loss at the femoral neck was demonstrated in this group of patients following stem cell transplantation. The implications of these findings for future fracture risk require further study.