Malar Rash and Polyarthritis Save

JAMA Clinical Challenge Case

58-year-old woman with a history of hypothyroidism presents with a 2-week history of joint pain and swelling in her right knee, which became migratory and later affected the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of her fingers; this followed a series of others being sick in the household.

Two weeks before, her 5-year-old grandson had a fever headaches, myalgias, malaise, and rash on the cheeks, trunk, and extremities. Last week her 10-month-old granddaughter developed a similar febrile illness and her 25-year-old daughter developed headaches, malaise, and arthralgias (wrists and knees), but no rash or fever. All manifestations in the family members resolved spontaneously within 1 week.

The patient was afebrile with normal vital signs and had amalar rash, but no rash on the trunk or extremities. She had swelling and tenderness of the MCP and PIP joints and had difficulty making a fist. Laboratory studies revealed a hemoglobin level of 11.5 g/dL, normal white blood cell and platelet counts, and normal results for a comprehensive metabolic panel. She had a positive antinuclear antibody (ANA) result (1:160 [homogeneous pattern; negative 1:80 serum dilution]). Testing for rheumatoid factor was negative; levels of inflammatory markers were normal.

What Would You Do Next?

1. Check for anti–double-stranded DNA and anti-Smith antibodies
2. Schedule bilateral hand radiographs
3. Order serologic testing for parvovirus
4. Order testing for anticyclic citrullinated peptide (CCP) antibody

Correct answer: is C. Order serologic testing for parvovirus

Pivotal to the correct diagnosis in the history of her children with a febrile illness associated with a facial rash (“slapped cheek”), suggestive of erythema infectiosum, also known as fifth disease. Given the recent history of similar illnesses in other family members, evaluation for chronic autoimmune diseases, eg, systemic lupus erythematosus (option A) and rheumatoid arthritis (option D), would be premature. 

Human parvovirus B19 commonly affects children who can infect healthy family members. The infectious phase begins 24 to 48 hours before the viral prodrome and lasts until the rash appears. Clinical presentation is variable, depending on age and immunologic status. The 5 well-established syndromes associated with parvovirus B19 include erythema infectiosum, arthropathy, transient aplastic crisis (TAC), transplacental fetal infection, and pure red blood cell aplasia (for more on these see the link to the original JAMA article)>

Joint symptoms are rare in children but common in adults, and they occur more often in women than in men.Arthropathy is often symmetric, affecting the small joints of the hands and feet. In children the arthritis may be symmetric, often involving the knees and ankles. Joint symptoms usually last for 1 to 3 weeks, although in some patients symptoms may persist for months.

The diagnosis of acute parvovirus infection rests with finding IgM antibodies to parvovirus B19.

By the time the rash appears, 90% of cases are IgM antibody–positive and stays detectable for up to 3 months.

IgG antibody appears within 1 week of illness and remains detectable for life.

Additional testing may include detection of viral nucleic acid (parvovirus B19 DNA) in blood by qualitative polymerase chain reaction. This test is most useful in immunocompromised patients because they may not test positive for IgM and IgG antibodies. 

Treatment for acute parvoviral arthritis is symptomatic with nonsteroidal anti-inflammatory drugs. 

Final Diagnosis

Parvovirus-associated arthritis