Specialty groups offer guide on which lab tests are best for diagnosing infectious diseases

The Infectious Diseases Society of America and the American Society for Microbiology have published a guide to help physicians determine which tests are most useful in diagnosing infectious diseases.

The guide outlines the appropriate contexts for various tests and also discusses tests that have little or no value for diagnosis. It is organized by anatomic systems, such as central nervous system infections, intraabdominal infections, and skin and soft tissue infections. Each section includes introductory concepts, a summary of key points, and tables that list the following:

• suspected agents,
• the most reliable tests to order,
• the samples and volumes to collect in order of preference,
• specimen transport devices, procedures, times, and temperatures, and
• notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times.

In particular, the guide emphasizes key tenets of specimen management, including precise labeling, rejection of poor-quality specimens, preference for specimens over swabs of specimens, collecting specimens before antibiotics are administered, and not demanding that a laboratory report “everything that grows.”

The guide was published online July 10 by Clinical Infectious Diseases.