Acute necrotizing encephalopathy as a H1N1 complication: A rare case

Abstract

Acute necrotizing encephalopathy of childhood (ANEC) is a rare type of encephalopathy seen generally in previously healthy children or infants of East Asian population. The pathology generally considered to be triggered by infectious diseases, mainly by viral agents. In this case report a previously healthy, 2-year –old, male children diagnosed as ANEC, occuring secondarily to H1N1 infection is presented. On MR images hyperintensity is present at bilateral thalamus and brainstem on T2WI and FLAIR. On gradient echo sequences, hemorrage is also present at bilateral thalamic region. ANEC does not have a specific symptomor typical neurological sign. It is important to remember that the typical lesions are generally seen in the gray matter of bilateral thalami. It is reported that administration of steroids within first 24 hours just after ANEC diagnosis was related to a better prognosis in patients without brain stem involvement. Early diagnosis mostly depends on knowing the imaging characteristics of ANEC and being aware of this rare entitiy.