Internal-Medicine

Answers and Explanations
1. (E) Each syndrome in the lysosomal storage
diseases is caused by a mutation-produced
deficiency in the activity of a lysosomal
enzyme. For example, Tay-Sachs disease is
caused by a deficiency of hexosaminidase A,
resulting in accumulation of GM2 ganglioside.
Gaucher’s disease is caused by a deficiency of
beta-glucocerebrosidase, resulting in an accumulation
of glucosylceramide. It has several
forms and, as in this case, is most common in
Ashkenazi (Eastern European) Jews. Type I
Gaucher’s disease, as described in this case, is
the most common type. Severe bone disease
and hepatosplenomegaly is characteristic.
Lipid-laden macrophages (Gaucher cells) are
found in the bone marrow. (Kasper, p. 2317)
2. (C) Anti-Sm detects a protein complexed to six
species of small nuclear ribonucleic acid
(RNA). It is believed to be very specific for SLE.
However, only 30% of patients have a positive
test. In the case presented, there are enough
clinical criteria (four) to confirm the diagnosis
of SLE with 98% specificity and 97% sensitivity.
(Kasper, p. 1964)
3. (D) Still’s disease (juvenile RA) in an adult
may present as fever of unknown origin.
Unfortunately, RF is often negative, and a
response to NSAIDs along with exclusion of
other diseases confirms the diagnosis. (Kasper,
p. 109)
4. (B) The sicca syndrome is a recognized feature
of Sjögren’s syndrome. It can be primary or
secondary to other autoimmune disorders such
as RA, SLE, scleroderma, or vasculitis. Primary
Sjögren’s syndrome is most common in
middle-aged women; sicca symptoms can also
occur as a complication of HIV infection or in
sarcoidosis. Sjögren’s syndrome is more likely
to have positive serology, while the serology in
sarcoid or HIV is negative. Both HIV and
Sjögren can have lymphocytic infiltration, but
in HIV it is predominantly by CD8 + lymphocytes,
whereas in Sjögren’s syndrome, the infiltration
is by CD4 + lymphocytes. In sarcoidosis,
biopsy reveals granulomas. (Kasper, p. 1991)
5. (D) ANA is the most important diagnostic
autoantibodies in patients being evaluated for
SLE. It is rare to have ANA negative SLE. The
other antibodies can occur in SLE but not as
sensitive for the diagnosis as ANA. AntidsDNA
and anti-SM are specific for SLE but
not sensitive. (Kasper, p. 1964)
6. (A) This patient has scleroderma and
esophageal symptoms are present in more than
50% of patients. They are due to the reduced
tone of the gastroesophageal sphincter and
dilation of the distal esophagus. Gastric and
small intestinal motility problems can also
occur. Vascular ectasia in the GI tract can result
in bleeding. (Kasper, p. 1984)
7. (D) The response of pain, stiffness, and
headaches to 40–60 mg of prednisone is dramatic
in giant cell arteritis. The duration of
treatment is not known but most patients
require treatment for more than 2 years. ESR is
used to monitor response to therapy. Patients
need treatment and evaluation for the complications
of long-term steroid use such as osteoporosis
and diabetes. (Kasper, p. 2009)
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