Contributed by Ming Yin, MD, PhD and Lisa J Robinson, MD
Published on line in October 2003
The patient is a white female in her 40s with no significant past medical history who presented initially in late June of 2003 after experiencing a severe syncope-like episode. This was associated with a sudden onset of facial flushing, headache, weakness, lightheadness, tachycardia, shortness of breath, a sensation of the impending loss of consciousness. She was playing the piano at the time of the episode. Paramedics at the scene found her pulse to be in the 140-150 range with a blood pressure of 60/palp, with fecal incontinent. She was taken to the emergency Department and was given intravenous fluid. Her blood pressure responded appropriately and symptoms resolved after about half an hour. The patient had a second episode of flushing hypotension a week later, without any apparent triggering factor. She showed similar symptoms to the previous attack and experienced nausea and vomiting. She was taken to an emergency Department, and EKG changes were noted. The patient underwent a coronary angiogram which did not reveal any lesions. Two weeks later, the patient had a third episode and was brought to the UPMC emergency Department. This was associated with headache, facial flushing and lightheadness. She took an aspirin, but continued to have worsening symptoms, including nausea, vomiting, tachycardia and fecal incontinence. She was found to be hypotensive in the ambulance and had several similar episodes after admission to the hospital. Each time, the patient responded to fluid challenge. Her family history is unremarkable. Her past medical is essential negative except for psoriasis. She denies any foreign travel or sick contact. Physical examination: the patient is afebrile. Her heart rate is 100, blood pressure 92/palp. She dose not have lymphadenopathy and hepatsplenomegaly. EKG and echocardiogram rule out cardiac abnormality. Chest X-ray is negative. An MRI of the brain was unremarkable. Her electrolytes and liver and kidney function tests are within the normal range.
Figure 1. The peripheral blood smear shows normal morphology.
Figures 2. Bone marrow aspirate smear at low power shows normal cellularity and trilineage hematopoiesis.
Figures 3, 4 and 5. Bone marrow aspirate smears at high power show increased mast cells that are spindle-shaped, some with cytoplasm projections.
Figure 6. Bone marrow biopsy at low power demonstrates normocellular marrow with no bony lesions.
Figures 7 and 8. Immunohistochemical stain for c-kit (CD117), a mast cell marker. The positive mast cells form aggregates, some surrounding small vessels or associated with lymphoid aggregates.
Figures 9 and 10. Immunohistochemical stain for tryptase, another mast cell marker. The spindled mast cells are positive for tryptase.
Flow cytometric immunophenotypic studies were not contributory.