Introduction The pandemic of swine origin influenza A H1N1v has been a difficult time for children, their parents and the health services that provide care for them. Flu is usually a self-limiting illness in children but complications can mean significant morbidity and mortality.

Aim The authors present two interesting cases of children from our centre with serious complications secondary to their H1N1v infection and review the relevant literature on the clinical, laboratory and pathological features that they demonstrated. The parents of both children have given us written consent to submit for publication.

Case one: A 5-year-old boy presented with influenza-type symptoms, but also with difficulty walking and dark brown urine. A number of investigations were performed which led to a diagnosis of rhabdomyolysis secondary to H1N1v infection. The boy was hyper-hydrated and improved. In the paper we discuss the pathology, epidemiology, differential diagnosis, management and outcomes for rhabdomyolysis in children particularly secondary to flu.

Case two: A 7 year-old girl presented with fever and malaise, and severe confusion and cognitive dysfunction which persisted after resolution of fevers. Interestingly she had no respiratory symptoms. She was treated initially for menigoencephalitis. CT head and cerebrospinal fluid analysis were normal. A diagnosis of H1N1v related encephalopathy was made which resolved after 4 days. The neurological sequelae of flu infection are discussed as well as the broader issues affecting families who receive a diagnosis of H1N1 and require admission.

Conclusion As with seasonal flu most otherwise healthy children who become infected with H1N1v are likely to have a self-limiting illness. There are however no longer-term or large number reports looking at the incidence and spectrum of complications from H1N1v flu. Oseltamivir holds no definite protection, although a national vaccination aims to reduce infection. Early recognition of complications, differential diagnoses and effective supportive management are pertinent as our cases demonstrate.