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Laboratory Studies
Hematologic studies may reveal leukocytosis or leukopenia with left
shift, thrombocytosis, or thrombocytopeniawithdisseminatedintravascular
coagulopathy (DIC).Erythrocyte sedimentation rate and C-reactive protein
levels are elevated.
Chemistry studies may reveal elevated aminotransferase levels,
hyponatremia (more commonly associated with Legionnaires disease than
with other pneumonias in adults), hypophosphatemia, elevated creatine
kinase levels, and other abnormalities. These abnormalities are not as
common in children as they are in adults.
Urinalysis commonly reveals proteinuria and hematuria.The urine
antigen test is a rapid, relatively inexpensive, and practical test for the
detection of L pneumophila antigen excreted in the urine or present in
pleural fluid.Urine antigen testing has 70% sensitivity and approaches
100% specificity. Sensitivity improves if urine samples are concentrated by
ultrafiltration and obtained within 7 days of the onset of pneumonia.
Figura 01
– Radiologic Manifestations of Legionelosis
