The Hematologist

Whatever Happened to the Microscope?

Thomas A. Bensinger, MD

Published on: March 01, 2014

Long before the development of the specialty of hematology, the discovery and use of the microscope demonstrated the findings of the blood cells in circulation.1

As every student of medicine knows, and especially anyone who is interested in hematology clearly understands, evaluation of the peripheral blood film by a well-trained clinician is an integral and, indeed, an essential part of the evaluation of most hematology patients. Thus, the use of the microscope has led the way in diagnosing many hematologic abnormalities.

We take pride in our ability to efficiently diagnose the patient’s problem by evaluating a freshly made and properly stained peripheral blood film. Highlighting the importance of this process, Blood includes a clinically relevant image along with a short case report in a recurring section titled “Blood Works.” The description of the disease process being highlighted in Blood Works is often accompanied by comments such as “This report demonstrates the need for review of the smear in any case of anemia diagnosis”2 or “A peripheral film review is imperative for correct diagnosis because automated analyzers frequently fail to properly count the giant-sized platelets.”3

Yet, two events have conspired in recent years to denigrate the value of the review of the peripheral blood film by the individual physician involved in the care of the patient. First, there has been less emphasis on the teaching of medical students and housestaff about the necessity of microscopically reviewing the peripheral blood film. The microscope has been essentially eliminated from the teaching wards of the hospital and can only be found in the pathology laboratory and is thus usually controlled by the pathologist or the laboratory technician. Second, even though we (hematologists) are recognized by Clinical Laboratory Improvement Amendments (CLIA)4 as competent to run a clinical laboratory, there is a determined effort to require extraordinary amounts of certification to permit the microscope to be present in a hematologist-run clinical laboratory. This position is also indirectly supported by the Current Procedural Terminology (CPT) reimbursement codes used by the Centers for Medicare and Medicaid Services (CMS) that provide no money for evaluating the peripheral blood film in an outpatient setting and that allow only a one-time payment for evaluation of the peripheral blood film on an inpatient (CPT code 85060). Practically, this code could be used in both the inpatient and outpatient setting, but CMS has chosen to honor it only in the inpatient setting. The single-payment issue persists even though follow-up evaluations of the peripheral blood film are often beneficial in determining response to therapy or in assessing disease status.

We make diagnoses in the office setting by reviewing the peripheral blood film while the patient is still present. This efficient approach allows us to order the most appropriate studies (instead of using the uninformed “shotgun” method that results in unnecessary tests), thereby saving both time and money for both the patient and the insurer.

Thus, the patient and society as a whole benefit from review of the peripheral blood film by the hematologist, and, in this day and age of cost containment, review of the peripheral blood film is a well-documented way to provide expert, thoughtfully managed, low-cost medical care. We must encourage use of the microscope by medical students, housestaff, and hematology fellows, and, of course, we need to enlighten CMS to the advantages of reviewing the peripheral blood film in an office setting.


  1. Van Leeuwenhoek A. Arcana Naturae Detecta, Delphis Batav, 1695.
  2. Soderquist C and Bagg A. Hereditary elliptocytosis. Blood. 2013;121:3066.
  3. Moiz, B and Rashid, A. BSS misdiagnosed as ITP. Blood. 2013;122:1693.
  4. CLIA Sec 493. 1443 Standard: Laboratory director qualifications. July 26, 1993.
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