Læknablaðið : fylgirit - 01.05.1978, Blaðsíða 11

J. J. CALABRO
Capriciousness is the outstanding feature of
Stills ’s disease, or juvenile rheumatoid arthritis
(JRA) as it is called in the United States.
Puzzling signs and symptoms, variable presenta-
tions, and unpredictabie patterns of disease
course are all hallmarks of this childhood illness.
It is only within recent years that this com-
piicated disease has become more accessible
to early diagnosis and more effective treatment.
Still's disease was first described in 1864 by
Cornil. Since then, a great deal of the literature
has been devoted to clinical descriptions and
efforts to classify various "subgroups" of the
disease. Even as early as 1890, Diamentberger,
another French investigator, pointed out that
rheumatoid arthritis (RA) in children could begin
acutely with high fever. He published observa-
tion on 35 patients, including 3 of his own, in
what he termed a "new rheumatism of children"
that began most often in large joints.
Diamentberger was the first to note the fre-
quency of growth disturbances, including micro-
gnathia, and the flare-ups and remissions that
are so typical of Still's disease. He also
concluded that the prognosis for RA appeared to
be more favorable in children than in adults.
In a scholarly report in 1897, Still separated
his 19 patients by the manner in which their
disease began. In 6 patients, he described
chronic polyarthritis, similar to adult RA, and
in one, Jaccoud's arthritis. In 12 cases, the
most informative group, he reported that joint
disease was accompanied by high fever, lympha-
denopathy, splenomegaly, hepatomegaly, and
pericarditis. Thus, Still's major contribution
was to describe most of the systemic manifesta-
tions that are now recognized as unique to JRA.
Today, the term Still's disease in generally
regarded as synonymous with childhood onset RA,
although the popular eponym is sometimes used
to describe an onset accompanied by prominent
systemic manifestations.
Childhood RA is usually confined to disease
beginning before age 16. It is rare before 6
months of age, and generally 2 onset peaks are
noted, one between ages 1 and 3, another from
8 to 12. In an English survey, Bywaters noted
one instance of Still's disease for every 15
PROGNOSIS IN JUVENILE
RHEUMATOID ARTHRITIS
hundred school children. No comparable survey
has been conducted in the United States where
there may be as many as 250.000 cases. But
this is only a rough estimate based on 57o of
adults with RA.
Despite such prevalence, the cause of Still's
disease is yet to be clarified. Currently, 2
mechanisms appear to be operative: infection by
some unidentified microorganism along with some
sort of immunologic disturbance. Yet, it was
not so long ago that teeth or tonsils were
removed because of the theory of "foeus of
infection." Since then, a number of micro-
organisms have been implicated, but none have
been established.
What about familial and genetic factors ? In
the only family survey, reported by Ansell in
1962, a familial aggregation of ankylosing
spondylitis greater than expected was found
among the male relatives of patients. This
impression has to be critically reexamined,
however, since by 1965 some of the 93 probands
with chronic polyarthritis may have gone on to
develop ankylosing spondylitis.
Twin studies give little support of any genetic
influence because of the low concordance rates
reported.
More recently, reports of a relatively higher
frequency of HL-A W27 in JRA than in controls
suggests some sort of genetic linkage. Of 26
patients typed by Rachelefsky and Terasaki,
42% had the antigen in contrast to only 6% of
267 controls. Of 24 children reported by
Sturrock, 29% also had the antigen. However,
these findings could not be confirmed in the
most recent and largest survey of 123 patients,
in which a comparable frequency (15 & 9%) of
W27 was disclosed among patients and controls.
Regarding various immunologic parameters,
it is difficult to assign a pathogenetic role to
rheumatoid factor because of its infrequency in
JRA. Recently, however, Torrigiani (and the
group at Taplow) have shown that seronegative
children with RA have IgG-anti-IgG rheumatoid
factor (not detected by the usual agglutination
tests) rather than IgM-anti-IgG rheumatoid
factor. Whether IgG antibody has the same
biologic activity as IgM rheumatoid factor is
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