Cold Agglutinin Recognition – Avoid Hypothermia

Cold agglutinins are autoantibodies that cause agglutination of red blood cells at colder temperatures.  Therefore, cold agglutinins are important to recognize in patients who receive intentional hypothermia.  Typical therapeutic uses of hypothermia include cold cardioplegia during cardiovascular surgery and in cases following cardiac arrest for neurologic stabilization. Hypothermia in patients with cold agglutinins may cause severe, life threatening complications due to hemolysis and microvascular occlusion. Some of the most commonly reported complications include acrocyanosis, stroke, and death.

The patient’s history may reveal cold intolerance and acrocyanosis. A focused review of systems could ask screening questions such as “How does cold weather affect your fingers?” Clues to recognition on physical exam are non-specific and include pallor, jaundice, lymphadenopathy, and hepatosplenomegaly.

Classic laboratory findings typically reveal an abnormal CBC with MCHC > 36, often with a comment attached to the report describing the presence of a probable cold agglutinin. Hemoglobinuria may be present. Routine Blood Bank Type and Screen testing may also alert to the presence of a cold autoantibody.

The clinical significance of these antibodies depends on their etiology and strength, although most cold agglutinins detected in the laboratory have little to no clinical significance. Healthy adults may have naturally occurring cold agglutinins in low concentrations. Pathologic cold agglutinins may be idiopathic, acutely present in the recovery phase of infections (Mycoplasma, mononucleosis, CMV), or occur in the setting of a B-cell lymphoproliferative disease. Strength and reactivity are dependent on antibody concentration (titer) as well as the temperature in which agglutination occurs, known as the thermal amplitude.

Whenever a cold agglutinin is suspected, a confirmatory cold agglutinin test can be ordered. Patients should be referred to a Hematologist, when indicated, and educated on the importance of cold avoidance.  Pathologists are also available to answer specific questions about cold agglutinins detected within the laboratory.

– Dr. Bruce Walker, Medical Director at PAH

New Testing in Microbiology

Helping you Understand and Interpret New Tests

Over the last decade molecular modalities have become more user friendly and have allowed local laboratories to provide more sensitive, accurate and faster results. Recently, the microbiology lab at Piedmont Atlanta has started offering several of these tests including: C. difficile and influenza virus assays with many more tests on the horizon (MRSA and Group B strep). Different testing methods may utilize different collection methods and provide different results. As always, the pathologist and microbiology staff at Piedmont are here to help our medical staff throughout the Piedmont system understand these new tests and how they should be interpreted in the context of your patients’ clinical presentation. If you have question about this new technology, or any other concerns/questions please contact us.

– Jeremiah R. Watkins, M.D., Microbiology Consulting Pathologist at PAH

Pathology office at Piedmont Atlanta: 404-605-3247

Microbiology at Atlanta can be reached via the lab: 404-605-3300

Submitting a Specimen for Pathologic Examination

Pathology Requisition Form and Specimen Labeling

Whether a small biopsy or large resection, all specimens should be submitted appropriately labeled and with a completed requisition form. This is necessary not only for legal compliance, but will help prevent unnecessary processing delays and provide valuable information to the pathologist for interpretation.

How do I know if the label and requisition form have been completed correctly?

If you can answer the five W’s, you are in good shape!

The specimen label and requisition should contain:

• Who is the patient? The patient’s name and date of birth (an Epic label will suffice).

• What and Where is the specimen from? What is the type of tissue (for example, biopsy, excision, fluid, cyst aspiration, etc.). Where in the body is the specimen from (for example, esophagus, right breast, right colon, etc.).

• When was the procedure performed.

• Why: The clinical History (This information can be placed on the requisition only). Believe it or not, this can have a significant impact on the diagnosis! This is often the most overlooked, but is extremely valuable. Knowing the clinical history in the appropriate clinical context in which the specimen was taken is vital to providing the best interpretation. Is there anything specific you are looking for? This does not have to be a lengthy dissertation; short and sweet will do the job! (example: left colon biopsy – normal endoscopy, history of watery diarrhea, R/O microscopic colitis; left arm skin biopsy – multiple raised, scaly plaques, present for 6 months, waxing and waning).

– Suneal Jannapureddy, M.D., Pathologist at Piedmont Henry Hospital