Many of you will have seen the movie, Lorenzo’s Oil, with Nick Nolte and Susan Sarandon. It tells of the moving story of a young boy with a serious neurological illness. Despite the considerable difficulties with both diagnosing and treating him, his parents, Augusta and Michael Odone, remain resolute in trying to help their son, Lorenzo. In the end, the movie leaves us with the possibility that there may be a treatment for his condition, a form of leukodystrophy- a group of conditions in which neurological symptoms occur due to metabolic damage to the myelin sheath that insulates nerve fibres.

Lorenzo’s Oil was released in 1992 and despite the 20 years that have followed, there remains no definitive cure for this group of disorders. However on a positive note, there have been huge strides in our ability to characterise and diagnose this group of disorders. The major reason for this is the giant leaps that medical science has made in clinical and molecular genetics. However, as with all rare diseases, the pace of change is so rapid that once in a while you need experts to provide you with a roadmap of how to proceed when you think you are dealing with one of these rare conditions. Regardless of whether you end up dealing with a ‘curable’ condition or not, just being able to provide a clear and definite diagnosis goes a long way to easing the many years or even decades of anxiety and distress that patients and their families experience when a diagnosis is not easily forthcoming.

In this issue of JNNP, Ahmed and colleagues have provided an outstanding review that is useful for any clinical neurologist http://jnnp.bmj.com/content/85/7/770.full) . They have succeeded in providing a clear step-by-step overview of how a neurologist should proceed when a patient presents with potential signs of a leukodystrophy. The article discusses clinical symptoms, MRI characteristics and other useful tests that can help achieve a diagnosis.

This is well-written and easy to follow, with case histories of patients included. A must read for clinical neurologists anywhere.