Substantial spontaneous long-term improvement in subacute sclerosing panencephalitis. Six cases from the Middle East and a review of the literature
W. S. Risk, F. S. Haddad and R. Chemali
Of 118 cases of subacute sclerosing panencephalitis identified in an
extensive follow-up study in the Middle East, six patients were found by
personal interview to have experienced substantial spontaneous long-term
improvement. To our knowledge, this rate of 5% for such improvement is
presently the most accurate estimate available. Relative to the onset of
clinical illness, the conditions of two patients are still improving four
to five years later, two are stable four to six years later, one relapsed
and died recently after eight years, and one is currently in relapse after
11 years. The condition of five patients had not progressed beyond stage 2
before improvement began. All patients had characteristic clinical and
electroencephalographic features. Two patients had brain biopsy specimens
showing panencephalitis without inclusions. Five patients had highly
elevated levels of serum and CSF measles antibodies. In this article, the
course of illness and extent of disability are described, published reports
of improvement are reviewed, and the possibility of subclinical illness is
discussed.