Hematology Interest Group
July 4, 2017
A 69-year-old female on vacation from New York was admitted to the ER after friends found her passed out in her hotel room. The patient stated she felt well until early morning when she awoke with severe nausea, followed by 5-10 episodes of forceful emesis described as either gastric contents or clear fluids and has since become weak and lightheaded. Other than this current trip, no recent travel. No history of travel to the tropics. She denies illness and any recent friends, family, or travel companions. No recent changes in medication.
Vitals were assessed and confirmed a fever of 99.8౦F(37.7౦C). Physical exam reveals a notable rash (petechiae) on lower legs, trace ankle edema, and appears well-nourished. The patient’s white blood cell (WBC) count is 11.3/μl, hemoglobin is 12.0g/dl, and platelet count is 35,000/μl. The WBC The peripheral blood smear shows ring form inclusions in red blood cells. The patient is admitted for initiation of treatment.
Constitutional: No history of tick bites
Red Blood Cell Count (RBC)
4.2 – 5.4 x106/uL
12-16 g/ dL
Mean Corpuscular Volume (MCV)
Heam Corpuscular Hemoglobin (MCH)
Mean Corpuscular Hemoglobin Concentration (MCHC)
Red Cell Distribution Width (RDW)
35 x 103/uL
140-440 x 103/uL
White Blood Cell Count (WBC)
4.8-10.8 x 103/uL
136 – 145 mmol/L
3.5 – 5.0 mmol/L
98 - 107 mmol/L
22 - 29 mmol/L
8.8 – 10.2 mg/dL
82- 100 mg/dL
0.1 – 1.3 mg/dL
<= 41 IU/L
0.0 - 43.9 U/mL
Lyme ABs: Bburgdorferi Ratio
Lyme ABs: Bburgdorferi Abs
50 – 70%
20 – 40%
1.2 - 3.4x103/uL
0-0.7 x 103/uL
0-0.5 x 103/uL
0-0.2 x 103/uL
Parasitic ring forms present in RBC.
PLT Count and Morphology
DxH 800 Interpretation/Flags
Babesia parasites in red blood cells on a wright giemsa stained blood smear at 50x.
Babesia parasites in red blood cells on a wright giemsa stained blood smear at 100x.
Pathologist Interpretation : The peripheral blood smear is reviewed as requested. No nucleated red blood cells are seen on scanning. The red cells are normochromic normocytic and normal in number. Numerous erythrocyte intracellular parasite forms are present. There is no significant polychromasia. The leukocytes are normal in number with an absolute monocytosis and unremarkable morphology. No blasts, lymphoma cells, or dysplastic cells are seen. The platelets are markedly decreased in number, and appear unremarkable.
69 year old female with numerous erythrocyte intracytoplasmic parasite forms. Clinical history favors babesiosis, however, no diagnostic "Maltese cross" forms are identified. Serologic testing and infectious disease consult is recommended.
Babesia species by PCR
Babesia microti by PCR
INTERPRETIVE INFORMATION: Babesia Species by PCR
A negative result does not rule out the presence of PCR inhibitors in the patient specimen or test-specific nucleic acid in concentrations below the level of detection by this test.
Test developed and characteristics determined by ARUP Laboratories. See Compliance Statement B: aruplab.com/cs
The CBC showed that the patient had thrombocytopenia and that 2% of the RBC showed intracellular inclusions favoring babesia. Finally, the Babesia Species by PCR from ARUP Laboratories came back positive, affirming the diagnosis of Babesiosis.
Babesiosis and thrombocytopenia instructions: Prescriptions for clindamycin and quinine in addition to Phenergan suppositories.
Babesia microti is transmitted by the bite of infected Ixodes scapularis ticks—typically, by the nymph stage of the tick. Symptoms occur 1-4 weeks following tick bite and are clinically nonspecific. The findings on routine laboratory testing frequently include hemolytic anemia and thrombocytopenia. Additional findings may include elevated levels of liver enzymes, blood urea nitrogen, and creatinine.
In symptomatic patients with acute infection, Babesia parasites typically can be detected by light-microscopic examination of blood smears, although multiple smears may need to be examined. Sometimes it can be difficult to distinguish between Babesia, Plasmodium parasites, or even debris (stain or platelet artifacts). In these cases, molecular and/or serologic methods can help confirm the diagnosis.
Samantha Dewey, MLS(ASCP)SH
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