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Ms. T has acute onset polyarticular joint symptoms. From her history of knee swelling, it is likely that she has arthritis rather than arthralgias. The pivotal points are acute onset and polyarticular involvement. Considering these points, and limiting the differential diagnosis based on the patient’s demographics and associated symptoms, we are able to come up with a fairly short list of probable etiologies.
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Given the acuity of the illness, infectious arthritides need to be strongly considered. Many viral illnesses can cause arthritis. Parvovirus is probably the most common. Bacterial illnesses can cause polyarthritis in myriad ways. Septic arthritides, discussed above, can be polyarticular as can disseminated gonorrhea. Bacterial endocarditis can cause aseptic polyarthritis and can cause arthralgias. Acute rheumatic fever classically causes a migratory polyarthritis and rash. Lyme disease, discussed above, is most commonly monoarticular but can present in a polyarticular fashion. Reactive arthritis, occurring after enteric or urogenital infections, is also a possibility.
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Although less likely, given the acute onset, primary rheumatologic diseases must also be considered. In a young woman with arthritis and a rash, SLE needs to be included on the differential diagnosis. As discussed above, rash, arthralgias, and arthritis are among the most common presenting symptoms in patients with SLE. Besides the acuity of the onset, the lack of other organ system involvement would be a little unusual for patients with SLE. RA would be less likely given the patient’s age; however, Still disease, a variant of RA, may present acutely in young patients.
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Given that the viral arthritides are more common than bacterial ones and, as far as we know, the patient has been previously well, viral arthritis is probably more likely than bacterial disease. Table 27-10 lists the differential diagnosis.
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On further history, Ms. T reports that 10 days before she came to see you she experienced 2 days of fatigue, myalgias, and fever to 39.4°C. There were no other symptoms. These symptoms resolved uneventfully.
She reports no travel outside Chicago, where she is in school, for the last year. She does not use recreational drugs. She is not sexually active.
On physical exam, she appears healthy. Her vital signs are temperature, 36.9°C; BP, 106/68 mm Hg; pulse, 84 bpm; RR, 14 breaths per minute. On extremity exam, her wrists have normal range of motion. There is pain with extremes of flexion and extension in the wrists and MCPs. There is mildly decreased range of motion and warmth in the knees as well as small effusions.
Skin exam reveals a diffuse erythematous rash with macules on the hands, feet, and distal extremities. Palms and soles are spared. The remainder of the exam was normal. There is no heart murmur.
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The patient’s history supports our initial hypothesis. The history of a recent febrile illness makes a viral or other postinfectious arthritis most likely. Lyme disease and bacterial endocarditis are very unlikely given her lack of suspicious exposure and the fact that she is otherwise presently well. SLE remains on the differential but is less likely.
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In a patient with acute polyarthritis, a detailed history of recent illnesses must be taken.
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Is the clinical information sufficient to make a diagnosis? If not, what other information do you need?
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Leading Hypothesis: Parvovirus
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Textbook Presentation
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Parvovirus is commonly seen in young people who are in contact with children (mothers, teachers, daycare workers, and pediatricians). Parvovirus often presents 10 days after a flu-like illness with a macular rash and moderately severe arthralgias of the joints of the upper extremities. There is no fever and symptoms improve over the course of weeks.
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There are 5 major manifestations of parvovirus infection in humans.
Erythema infectiosum (fifth disease) in children
Acute arthropathy in adults
Transient aplastic crises in patients with chronic hemolytic diseases
Chronic anemia in immunocompromised persons
Fetal death complicating maternal infection prior to 20 weeks gestation.
In adults, the acute disease often proceeds in 2 phases with the arthritis following a systemic febrile infection.
Initial phase
Nonspecific symptoms such as fever, malaise, headache, myalgia, diarrhea, and pruritus
Generally resembles a nonspecific viral infection
Second phase
Follows initial phase by 10 days with joint symptoms and rash dominating the clinical picture.
Arthropathy accompanies about 50% of adult infections.
The arthritis is a symmetric polyarthritis commonly involving the following joints:
(1) Elbows
(2) Wrists
(3) Hands
(4) Knees
(5) Ankles
(6) Feet
The rash lasts 2–3 days.
The incidence of parvovirus infection peaks between January and June.
Attack rates are 50–60%.
Contact with children is common among patients.
Other viruses cause arthritis less commonly. These are listed in Table 27-11.
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Evidence-Based Diagnosis
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The diagnosis is made by identifying IgM to parvovirus in the serum of patients with a suspicious symptom complex.
The differential diagnosis of parvovirus includes SLE and the differentiation of these diseases can be challenging.
Both may present with arthritis, arthralgias, and rash.
Both are more common in women than men.
ANA can be transiently elevated in patients with parvovirus.
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The treatment of parvovirus is symptomatic.
NSAIDs generally provide good relief of symptoms.
Symptoms usually resolve within a couple of weeks, but as many as 10% of patients have symptoms that last longer.