A few words on "rheumatology panels." Doing a "rheumatology panel" will never be the right answer. The diagnosis of rheumatologic disease is clinical with specific clinical criteria for each illness. While antinuclear antibody (ANA), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and other tests may be useful in supporting a clinical diagnosis and assessing disease activity, these tests have poor specificity and may be positive in a variety of disease states. A positive ANA without a clinical diagnosis is meaningless. Likewise, RF helps to gauge prognosis (seropositive vs. seronegative) in rheumatoid arthritis (RA), but has very limited value as a diagnostic test. RF may also be positive in sarcoidosis, viral infections (especially hepatitis C), and autoimmune diseases such as granulomatosis with polyangiitis (formerly known as Wegener granulomatosis), as well as a variety of primary lung and liver diseases. ESR and CRP may support the clinical impression of inflammatory disease, but are again nonspecific.
A 43-year-old female presents with body aches and stiffness, which are worse in the morning. She further describes a low-grade fever and pain in her hands, feet, and left knee. She feels that her grip strength is diminished. These symptoms started rather abruptly 2 weeks ago and have not responded to acetaminophen.
She frequently camps with her family. She remembers that 1 week they could not go because her 8-year-old daughter had a fever, mild diarrhea, abdominal pain, and a skin rash ("legs, arms, and especially face were red and warm, and she seemed 'flushed' all the time"). Her daughter's symptoms resolved in a few days, she did not see a doctor, and no one else was sick. She has no other illnesses, and review of systems is otherwise negative.
On physical examination, her vitals are normal. She is unable to close her hands completely. Although the physical examination is somewhat limited by pain, there appears to be swelling of all metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints, as well as mild erythema over the MCP joints bilaterally. In addition, upon examination of the left knee, the bulge sign (indicating effusion) is detected.
Question 11.1.1 If found on physical examination, which of the following would be LEAST useful in helping you in narrow your diagnosis?
A) Bilateral metatarsophalangeal (MTP) joint swelling and tenderness.
B) Painless oral ulcerations, with clean edges.
C) Firm, slightly tender subcutaneous nodules at the olecranon bursae.
D) A "bull's eye" rash in the right axilla.
E) Icterus and tender hepatomegaly.
Answer 11.1.1 The correct answer is "A." This patient presents with polyarticular inflammatory arthritis of unclear etiology. While ...