Dystonic opisthotonus: A “red flag” for neurodegeneration with brain iron accumulation syndromes?

Abstract

Back arching was reported in one of the very first patients with neurodegeneration with brain iron accumulation syndrome (NBIAs) published in 1936. However, recent reports have mainly focused on the genetic and imaging aspects of these disorders, and the phenotypic characterization of the dystonia has been lost. In evaluating patients with NBIAs in our centers, we have observed that action-induced dystonic opisthotonus is a common and characteristic feature of NBIAs. Here, we present a case series of patients with NBIAs presenting this feature demonstrated by videos. We suggest that dystonic opisthotonus could be a useful “red flag” for clinicians to suspect NBIAs, and we discuss the differential diagnosis of this feature. This would be particularly useful in identifying patients with NBIAs and no iron accumulation as yet on brain imaging (for example, as in phospholipase A2, group IV (cytosolic, calcium-independent) [PLA2G6]-related disorders), and it has management implications. © 2013 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Amelioration of Dystonic Opisthotonus in Pantothenate Kinase‐Associated Neurodegeneration Syndrome with Absent “Eye‐of‐the‐Tiger” Sign Following Bilateral Pallidal Deep Brain Stimulation

“…Our case strengthens this clinical association and highlights the importance of recognizing dystonic opisthotonus as a useful phenotypic clue of PKAN syndrome, particularly in patients with absent eye‐of‐the‐tiger sign. However, this feature can also occur in other conditions . Suspicion for genetic testing should, therefore, be guided by careful history in conjunction with other NBIA signs (such as oromandibular dystonia).…”

Diagnosis and Treatment of Dystonia

“…Another strategy sometimes recommended follows a “red flag” approach in which diagnostic testing is guided by the identification of telltale clinical features, such as a corneal Kayser-Fleischer ring or liver disease in Wilson’s disease. 19,20 This strategy is not ideal because most dystonic disorders lack red flags. Another strategy sometimes recommended is to test only for disorders where there are specific treatments that target underlying etiologies, such as Wilson’s disease where copper-lowering therapies are life saving.…”

PLA2G6 ‐Associated Neurodegeneration: Report of a Novel Mutation in Two Siblings with Strikingly Different Clinical Presentation

“…In this regard, exome‐NGS is an unbiased approach that may contribute to the elucidation of different phenotypic expressions, but more samples have to be examined to reach any conclusion. A presenting symptom in one sibling was opisthotonus, a hallmark of NBIA . In this case, opisthotonus was early, subsiding as the patient continued to deteriorate.…”