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Subacute sclerosing panencephalitis (SSPE) is a late complication of measles, occurring multiple years after primary infection (mean 8 years). The exact pathophysiology is unknown, but the general hypothesis is that chronic replication of measles virus occurs in neurons and oligodendrocytes. Since the introduction of immunization against measles in 1976, SSPE is very rare in the Netherlands with 6 registered cases since 1988. Only 4 of these cases were immunized against measles and all on a later age (4, 8, 4 and 9 years, respectively). Before the introduction of the immunization program against measles, 10 to 15 cases of SSPE were reported each year. There is no effective treatment for SSPE. The clinical course is variable, but death usually occurs within 1 to 3 years after diagnosis.
A 17-year-old, previously healthy, young man came to the emergency room because of progressive cognitive problems and jerks in his whole body, which started a few weeks earlier. There was a general slowness of movements and risk of falling due to the jerking movements. As a consequence of his parents’ religious beliefs, he was not immunized against measles and he had acquired measles infection at 4 years of age. On neurological examination, he was remarkable bradyphrenic. There was almost no spontaneous speech and given answers were short, but adequate. His visuoconstructive functions were disturbed. He had decreased facial expression, a hypophonic voice, overall bradykinesia and cogwheel rigidity of the left arm. Myoclonic jerks were present in trunk, neck and all extremities and some truncal ataxia was visible. General laboratory research and an MRI scan of the brain were normal. Based on high clinical suspicion of SSPE, an EEG was performed. During registration, myoclonic jerks were visible of the left side of the body (1 – 3 per second) with simultaneously occurring periodic complexes with bifrontal, symmetric, high-voltage polymorphic delta waves. These are called Radermeckercomplexes and are specific for SSPE. Cerebrospinal fluid examination confirmed the diagnosis with a positive Goldman-Witmer coefficient for measles. After initial diagnosis we started treatment with carbamazepine, which reduced the myoclonic jerks. In an attempt to alter the disease course, treatment with isoprinosine and intramuscular interferon-bèta 1a was started, even though its effectiveness for SSPE is unproven. The first 3 months after initial diagnosis, patients’ clinical condition stayed relatively stable, although cognitive disturbances progressed, visual disturbances occurred and he spoke even less. The weeks hereafter he deteriorated rapidly and became incontinent and comatose with a severe opisthotonus. Autonomic dysregulation occurred with hyperhidrosis, hyperthermia and intermittently hyperventilation. We started treatment with benzodiazepines, which reduced the opisthotonus and patient seemed more comfortable hereafter. He went home with palliative care and passed away a few days later.
SSPE is a late complication of measles infection and still occurs in the Netherlands. The description of our patients’ disease course, in the absence of an effective treatment, emphasizes the importance of prevention by means of immunization against measles.