Læknablaðið : fylgirit - 01.05.1978, Page 14

of vertebral bodies and apophyseal narrowing,
chiefly at C-2 and C-3.
Asymptomatic sacroiliitis is another early X-
ray finding that appears to correlate with hip
involvement (shown here), rheumatoid factor, and
with onset of disease at 10 years of age or older.
Axial articulations other than the cervical and
sacroiliac are rarely involved. On the other hand,
hips are frequently involved and when progressive •
may rapidly produce ankylosis.
The joint manifestations are the most prominent
component of a polyarticular onset. Nevertheless,
rash, lymphadenopathy, splenomegaly, hepatomegaly,
pericarditis, and pneumonitis do occur, but are
less frequent than in acute febrile onset. Fever,
on the other hand, is frequent (38 out of 48
patients) but is invariably low grade, with one
or two daily peaks less than 39°C (102°F).
Subcutaneous nodules, present in 8 of our
chfldren, occurred only in this mode of onset.
In Oligoarticular onset, the arthritis is usuaUy
insidious with swelling and stiffness and little or
no pain. The initial joint most often involved is
the knee.
The knee proved to be the initial site in 14 of
our 32 patients. Next in order of frequency
were the hip (5 patients), ankle (4), and elbow
(3). In 2 children, a single metatarsophalangeal
joint was affected, and in one chUd, a proximal
interphalangeal joint of the hand. Painful
tendinitis or bursitis of the heel was the initial
manifestation in 3 chUdren.
When progressive, heel involvement may cause
premature formation and closure of the apophysis
(noted here on the involved left side). Note also
soft tissue radiodensities from achUlobursitis
and achillotendinitis as well as erosions and
loss of the fine trabecular pattern of the
calcaneus.
Comparatively few systemic manifestations
occur in this form of disease. Low-grade
quotidian fever was present in only half of the
group. Hash, lymphadenopathy, splenomegaly,
and hepatomegaly were only occasionaUy observec.
whUe cardiac and pulmonary involvement were
notably absent.
Clearly, the most important and potentially
serious systemic manifestation is chronic
iridocyclitis. It occurred in 7 of 32 patients,
or 227o, a frequency comparable to that reported
by others.
Does the laboratory help in early diagnosis?
There is no single consistent laboratory
abnormality. Elevation of the erythrocyte
sedimentation rate and low-grade anemia are
frequent, somewhat less so in oligoarticular
onset. While nonspecific, each of these abnor-
malities are especiaUy helpful in following the
• course of individual patients.
One of the most consistent abnormaUties in
acute febrile onset is a striking neutrophiUc
leukocytosis, usually between 20,000 and 30,000
— and sometime higher; it was up to 80,000 in
one patient. Leukocytosis is less frequent in
polyarticular onset, and counts are generaUy
between 12 and 20,000. The white cell count
is usually normal in oligoarticular onset.
Leukopenia rarely occurs, and its presence
should lead one to suspect leukemia or systemic
lupus erythematosus.
Prolonged and elevated ASO titers, from 400
to 2,500 Todd units, occurred in 29Jo of our
patients, and were rather even distributed among
each mode of onset. Intramuscular monthly
injections of benzathine penicillin over a period
of 12 months failed to lower titers in 6 of our
patients, seemingly confirming the nonspecific
nature of these titers.
Nineteen patients had latex titers of 1:160 or
greater, which was most often found in poly-
articular onset (297o). Rheumatoid factor occurs
primarily in children with disease beginning after
12 years of age, and appears to correlate with
subcutaneous nodules and a poorer functional
outcome.
The titers of ANA are lower in JRA than those
found in SLE. Their incidence is higher in girls
as well as in patients with chronic iridocyclitis,
as recently disclosed by Schaller, in 51 of 58
patients, or 887o. ANA titers evolved concomi-
tantly with the onset of iridocyclitis in 8 of these
patients whose titers were normal previously.
ANA may thus prove useful in identifying patients
at risk for iridocyclitis.
Unlike ANA, LE cells occur only rarely in
JRA.
The significance of serum immunoglobulins
has already been cited. Their determination
also serves to detect patients with underlying
agammaglobulinemia or selective IgA deficiency.
The results of synovial fluid analysis vary
considerably, and do not necessarily correlate
with the intensity of the underlying arthritis.
The average white cell count is 10,000 cells,
but the range is wide, from only 150 to 50,000
cells. Complement values are usually but not
always depressed.
Early X-ray findings include juxta-articular
demineralization, radiodensities from soft tissue
swelling and effusion, periosteal proliferation,
and early closure of epiphyses. Occasionally,
accelerated epiphyseal maturation and metaphyseal
overgrowth occur. Erosions are only late findings;
their early presence should lead one to suspect
leukemia or some other form of malignancy.
Let us now examine the COURSE OF DISEASE
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