Case Presentation: A 70-year-old healthy active male with past medical history of Hypertension and tobacco use 1 pack per day, presented with flushing, weakness, pre-syncope, skin hives, diarrhea, shortness of breath and unintentional 20 pounds loss. Recently returned from a trip to Cuba and his PCP performed blood work and stool studies , significant for ESR 70, and eosinophilia 12.9, alkaline phosphatase 709 and stools positive for Dientamoeba fragilis. He was started on Mebendazole with no improvement. Patient continued to have abdominal cramps, diarrhea, vomiting, weakness with multiple falls with no loss of consciousness , and hypotension. He had several episodes of flushing with diaphoresis not associated with tachycardia or hypertension. CT head showed mild cortical atrophy with no acute intracranial hemorrhage or mass. Chest x-ray showed multiple sclerotic osseous lesions suspicious for metastasis. CT abdomen and pelvis showed multiple hypodense lesions in the spleen with diffuse sclerotic lesions. Nuclear bone scan showed abnormal diffuse increased radiotracer uptake with stippled appearance in the spine, ribs, pelvis, bilateral femurs, bilateral humeri, sternum resulting in “SuperScan appearance” of diffuse osseus metastatic disease. Somatostatin receptor scintigraphy was negative with no evidence for Pentetreotide avid neuroendocrine tumor. Flow cytometry of peripheral blood showed no evidence of typically B or T-cell population with no significant CD34 positive immunophenotypic blasts population identified, but mast cells identified by positive CD117. SPEP, UPEP light chains were negative, tissue transglutaminase IgA was normal. Serum tryptase came back with high level 141, and CT-guided left iliac bone biopsy was done and pathology showed striking proliferation of densely packed spindled mast cells along bone trabeculae with focal fibrosis and marked osteosclerosis. A diagnosis of systemic mastocytosis was made, the patient was started on Cetrizine, Famotidine, Aspirin. He had significant improvement of his flushing, sweats, and weakness, but continued to have diarrhea, so montelukast was added to his regimen. The patient did quite well with near resolution of his symptoms, with periodic episodes for which Benadryl, loperamide, and epinephrine pen for anaphylaxsis were started.
Discussion: Systemic mastocytosis is a myeloproliferative disorder characterized by accumulation of pathological mast cells in multiple tissues, which can affect children or adults. The prevalance of over mastocytosis has been estimated to be about 10 cases per 100,000 . Two main disease variants are recognized by world health organization(WHO): Cutaneous mastocytosis typically presents as an urticaria pigmentosa, and systemic mastocytosis characterized by neoplastic mast cell infiltration of extracutaneous tissues like Bone marrow, gastrointestinal tract, liver, spleen, or lymph nodes.
Conclusions: Mastocytosis is a disease that can range from indolent to aggressive form with fatal outcome and need high sense of clinical suspicion. Diagnosis is confirmed by fulfillment of specific diagnostic criteria. Available treatment options include antihistamines and H2 blockers, leukotriene antagonists, sodium cromolyn, Aspirin, Omalizumab, and biphosphonates for mastocytosis related osteoporosis.
