03-12-2008, 07:15 AM
1]e
2]a
An erythrocyte sedimentation rate (ESR), although nonspecific, may indicate the presence of serious disease (osteomyelitis, giant cell arteritis, malignancy) if > 100 mm/hour. A normal ESR may be useful in excluding a significant inflammatory process. Given the significant proportion of FUOs secondary to collagen-vascular disease, rheumatoid factor and ANA serology are justified, although results should be correlated with clinical presentation. Tuberculosis screening by PPD skin testing is justified given the proportion of FUOs secondary to undiagnosed tuberculosis infections. However, infections are usually extrapulmonary and more than 50% of PPD skin tests in this setting are falsely negative due to anergy. Further testing with biopsy of lymph nodes, bone marrow, or liver may be needed to make the diagnosis of tuberculosis presenting as FUO. Blood cultures should be obtained on at least 3 different occasions and the laboratory notified if organisms associated with "culture-negative" endocarditis (e.g., Coxiella, HACEK group, Bartonella) are suspected. A chest radiograph should be done. Additionally, abdominal CT scanning has replaced exploratory laparotomy as the procedure of choice to exclude occult abdominal and pelvic infections. If mental status abnormalities are detected upon exam, a lumbar puncture may be useful. Screening colonoscopy, mammography, and PSA do not detect malignancies that are most likely to present with FUO. The most common malignancies to present with FUO are lymphoma, leukemia, renal cell carcinoma, and hepatoma.
FUO, fever of unknown origin, is defined as an illness characterized by fever greater than 38.3°C of at least 3 weeks duration with no obvious cause despite extensive evaluation. Infections are the most common source of FUO in children and young adults. The most common infections include tuberculosis and abscesses. In older adults, collagen-vascular diseases, such as giant cell arteritis and rheumatoid arthritis, are more likely sources of FUO.
2]a
An erythrocyte sedimentation rate (ESR), although nonspecific, may indicate the presence of serious disease (osteomyelitis, giant cell arteritis, malignancy) if > 100 mm/hour. A normal ESR may be useful in excluding a significant inflammatory process. Given the significant proportion of FUOs secondary to collagen-vascular disease, rheumatoid factor and ANA serology are justified, although results should be correlated with clinical presentation. Tuberculosis screening by PPD skin testing is justified given the proportion of FUOs secondary to undiagnosed tuberculosis infections. However, infections are usually extrapulmonary and more than 50% of PPD skin tests in this setting are falsely negative due to anergy. Further testing with biopsy of lymph nodes, bone marrow, or liver may be needed to make the diagnosis of tuberculosis presenting as FUO. Blood cultures should be obtained on at least 3 different occasions and the laboratory notified if organisms associated with "culture-negative" endocarditis (e.g., Coxiella, HACEK group, Bartonella) are suspected. A chest radiograph should be done. Additionally, abdominal CT scanning has replaced exploratory laparotomy as the procedure of choice to exclude occult abdominal and pelvic infections. If mental status abnormalities are detected upon exam, a lumbar puncture may be useful. Screening colonoscopy, mammography, and PSA do not detect malignancies that are most likely to present with FUO. The most common malignancies to present with FUO are lymphoma, leukemia, renal cell carcinoma, and hepatoma.
FUO, fever of unknown origin, is defined as an illness characterized by fever greater than 38.3°C of at least 3 weeks duration with no obvious cause despite extensive evaluation. Infections are the most common source of FUO in children and young adults. The most common infections include tuberculosis and abscesses. In older adults, collagen-vascular diseases, such as giant cell arteritis and rheumatoid arthritis, are more likely sources of FUO.